Merge pull request #1028 from hashicorp/f-continuous-state

core: state management refactor to prepare for continuous state

command/apply_test.go

@@ -15,7 +15,6 @@ import (
 	"testing"
 	"time"
 
-	"github.com/hashicorp/terraform/remote"
 	"github.com/hashicorp/terraform/terraform"
 	"github.com/mitchellh/cli"
 )
@@ -408,8 +407,9 @@ func TestApply_plan_remoteState(t *testing.T) {
 	defer func() { test = true }()
 	tmp, cwd := testCwd(t)
 	defer testFixCwd(t, tmp, cwd)
-	if err := remote.EnsureDirectory(); err != nil {
+	remoteStatePath := filepath.Join(tmp, DefaultDataDir, DefaultStateFilename)
-		t.Fatalf("err: %v", err)
+	if err := os.MkdirAll(filepath.Dir(remoteStatePath), 0755); err != nil {
+		t.Fatalf("err: %s", err)
 	}
 
 	// Set some default reader/writers for the inputs
@@ -448,21 +448,13 @@ func TestApply_plan_remoteState(t *testing.T) {
 	}
 
 	// State file should be not be installed
-	exists, err := remote.ExistsFile(DefaultStateFilename)
+	if _, err := os.Stat(filepath.Join(tmp, DefaultStateFilename)); err == nil {
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	if exists {
 		t.Fatalf("State path should not exist")
 	}
 
 	// Check for remote state
-	output, _, err := remote.ReadLocalState()
+	if _, err := os.Stat(remoteStatePath); err != nil {
-	if err != nil {
+		t.Fatalf("missing remote state: %s", err)
-		t.Fatalf("err: %v", err)
-	}
-	if output == nil {
-		t.Fatalf("missing remote state")
 	}
 }
 

command/command.go

@@ -10,6 +10,9 @@ import (
 // Set to true when we're testing
 var test bool = false
 
+// DefaultDataDir is the default directory for storing local data.
+const DefaultDataDir = ".terraform"
+
 // DefaultStateFilename is the default filename used for the state file.
 const DefaultStateFilename = "terraform.tfstate"
 

command/command_test.go

@@ -178,17 +178,20 @@ func testTempDir(t *testing.T) string {
 // testCwdDir is used to change the current working directory
 // into a test directory that should be remoted after
 func testCwd(t *testing.T) (string, string) {
-	tmp, err := ioutil.TempDir("", "remote")
+	tmp, err := ioutil.TempDir("", "tf")
 	if err != nil {
 		t.Fatalf("err: %v", err)
 	}
+
 	cwd, err := os.Getwd()
 	if err != nil {
 		t.Fatalf("err: %v", err)
 	}
+
 	if err := os.Chdir(tmp); err != nil {
 		t.Fatalf("err: %v", err)
 	}
+
 	return tmp, cwd
 }
 
@@ -197,6 +200,7 @@ func testFixCwd(t *testing.T, tmp, cwd string) {
 	if err := os.Chdir(cwd); err != nil {
 		t.Fatalf("err: %v", err)
 	}
+
 	if err := os.RemoveAll(tmp); err != nil {
 		t.Fatalf("err: %v", err)
 	}

command/flag_kv.go

@@ -9,15 +9,15 @@ import (
 	"github.com/mitchellh/go-homedir"
 )
 
-// FlagVar is a flag.Value implementation for parsing user variables
+// FlagKV is a flag.Value implementation for parsing user variables
 // from the command-line in the format of '-var key=value'.
-type FlagVar map[string]string
+type FlagKV map[string]string
 
-func (v *FlagVar) String() string {
+func (v *FlagKV) String() string {
 	return ""
 }
 
-func (v *FlagVar) Set(raw string) error {
+func (v *FlagKV) Set(raw string) error {
 	idx := strings.Index(raw, "=")
 	if idx == -1 {
 		return fmt.Errorf("No '=' value in arg: %s", raw)
@@ -32,16 +32,16 @@ func (v *FlagVar) Set(raw string) error {
 	return nil
 }
 
-// FlagVarFile is a flag.Value implementation for parsing user variables
+// FlagKVFile is a flag.Value implementation for parsing user variables
 // from the command line in the form of files. i.e. '-var-file=foo'
-type FlagVarFile map[string]string
+type FlagKVFile map[string]string
 
-func (v *FlagVarFile) String() string {
+func (v *FlagKVFile) String() string {
 	return ""
 }
 
-func (v *FlagVarFile) Set(raw string) error {
+func (v *FlagKVFile) Set(raw string) error {
-	vs, err := loadVarFile(raw)
+	vs, err := loadKVFile(raw)
 	if err != nil {
 		return err
 	}
@@ -57,7 +57,7 @@ func (v *FlagVarFile) Set(raw string) error {
 	return nil
 }
 
-func loadVarFile(rawPath string) (map[string]string, error) {
+func loadKVFile(rawPath string) (map[string]string, error) {
 	path, err := homedir.Expand(rawPath)
 	if err != nil {
 		return nil, fmt.Errorf(

command/flag_kv_test.go

@@ -7,11 +7,11 @@ import (
 	"testing"
 )
 
-func TestFlagVar_impl(t *testing.T) {
+func TestFlagKV_impl(t *testing.T) {
-	var _ flag.Value = new(FlagVar)
+	var _ flag.Value = new(FlagKV)
 }
 
-func TestFlagVar(t *testing.T) {
+func TestFlagKV(t *testing.T) {
 	cases := []struct {
 		Input  string
 		Output map[string]string
@@ -43,7 +43,7 @@ func TestFlagVar(t *testing.T) {
 	}
 
 	for _, tc := range cases {
-		f := new(FlagVar)
+		f := new(FlagKV)
 		err := f.Set(tc.Input)
 		if (err != nil) != tc.Error {
 			t.Fatalf("bad error. Input: %#v", tc.Input)
@@ -56,11 +56,11 @@ func TestFlagVar(t *testing.T) {
 	}
 }
 
-func TestFlagVarFile_impl(t *testing.T) {
+func TestFlagKVFile_impl(t *testing.T) {
-	var _ flag.Value = new(FlagVarFile)
+	var _ flag.Value = new(FlagKVFile)
 }
 
-func TestFlagVarFile(t *testing.T) {
+func TestFlagKVFile(t *testing.T) {
 	inputLibucl := `
 foo = "bar"
 `
@@ -93,7 +93,7 @@ foo = "bar"
 			t.Fatalf("err: %s", err)
 		}
 
-		f := new(FlagVarFile)
+		f := new(FlagKVFile)
 		err := f.Set(path)
 		if (err != nil) != tc.Error {
 			t.Fatalf("bad error. Input: %#v", tc.Input)

command/init.go

@@ -8,7 +8,6 @@ import (
 
 	"github.com/hashicorp/terraform/config"
 	"github.com/hashicorp/terraform/config/module"
-	"github.com/hashicorp/terraform/remote"
 	"github.com/hashicorp/terraform/terraform"
 )
 
@@ -19,14 +18,12 @@ type InitCommand struct {
 }
 
 func (c *InitCommand) Run(args []string) int {
-	var remoteBackend, remoteAddress, remoteAccessToken, remoteName, remotePath string
+	var remoteBackend string
 	args = c.Meta.process(args, false)
+	remoteConfig := make(map[string]string)
 	cmdFlags := flag.NewFlagSet("init", flag.ContinueOnError)
-	cmdFlags.StringVar(&remoteBackend, "backend", "atlas", "")
+	cmdFlags.StringVar(&remoteBackend, "backend", "", "")
-	cmdFlags.StringVar(&remoteAddress, "address", "", "")
+	cmdFlags.Var((*FlagKV)(&remoteConfig), "backend-config", "config")
-	cmdFlags.StringVar(&remoteAccessToken, "access-token", "", "")
-	cmdFlags.StringVar(&remoteName, "name", "", "")
-	cmdFlags.StringVar(&remotePath, "path", "", "")
 	cmdFlags.Usage = func() { c.Ui.Error(c.Help()) }
 	if err := cmdFlags.Parse(args); err != nil {
 		return 1
@@ -92,37 +89,34 @@ func (c *InitCommand) Run(args []string) int {
 	}
 
 	// Handle remote state if configured
-	if remoteAddress != "" || remoteAccessToken != "" || remoteName != "" || remotePath != "" {
+	if remoteBackend != "" {
 		var remoteConf terraform.RemoteState
 		remoteConf.Type = remoteBackend
-		remoteConf.Config = map[string]string{
+		remoteConf.Config = remoteConfig
-			"address":      remoteAddress,
-			"access_token": remoteAccessToken,
-			"name":         remoteName,
-			"path":         remotePath,
-		}
 
-		// Ensure remote state is not already enabled
+		state, err := c.State()
-		haveLocal, err := remote.HaveLocalState()
 		if err != nil {
-			c.Ui.Error(fmt.Sprintf("Failed to check for local state: %v", err))
+			c.Ui.Error(fmt.Sprintf("Error checking for state: %s", err))
 			return 1
 		}
-		if haveLocal {
+		if state != nil {
-			c.Ui.Error("Remote state is already enabled. Aborting.")
+			s := state.State()
+			if !s.Empty() {
+				c.Ui.Error(fmt.Sprintf(
+					"State file already exists and is not empty! Please remove this\n" +
+						"state file before initializing. Note that removing the state file\n" +
+						"may result in a loss of information since Terraform uses this\n" +
+						"to track your infrastructure."))
 				return 1
 			}
-
+			if s.IsRemote() {
-		// Check if we have the non-managed state file
+				c.Ui.Error(fmt.Sprintf(
-		haveNonManaged, err := remote.ExistsFile(DefaultStateFilename)
+					"State file already exists with remote state enabled! Please remove this\n" +
-		if err != nil {
+						"state file before initializing. Note that removing the state file\n" +
-			c.Ui.Error(fmt.Sprintf("Failed to check for state file: %v", err))
+						"may result in a loss of information since Terraform uses this\n" +
+						"to track your infrastructure."))
 				return 1
 			}
-		if haveNonManaged {
-			c.Ui.Error(fmt.Sprintf("Existing state file '%s' found. Aborting.",
-				DefaultStateFilename))
-			return 1
 		}
 
 		// Initialize a blank state file with remote enabled
@@ -149,20 +143,11 @@ Usage: terraform init [options] SOURCE [PATH]
 
 Options:
 
-  -address=url           URL of the remote storage server.
+  -backend=atlas         Specifies the type of remote backend. If not
-                         Required for HTTP backend, optional for Atlas and Consul.
+                         specified, local storage will be used.
 
-  -access-token=token    Authentication token for state storage server.
+  -backend-config="k=v"  Specifies configuration for the remote storage
-                         Required for Atlas backend, optional for Consul.
+                         backend. This can be specified multiple times.
-
-  -backend=atlas         Specifies the type of remote backend. Must be one
-                         of Atlas, Consul, or HTTP. Defaults to atlas.
-
-  -name=name             Name of the state file in the state storage server.
-                         Required for Atlas backend.
-
-  -path=path             Path of the remote state in Consul. Required for the
-                         Consul backend.
 
 `
 	return strings.TrimSpace(helpText)

command/init_test.go

@@ -5,7 +5,6 @@ import (
 	"path/filepath"
 	"testing"
 
-	"github.com/hashicorp/terraform/remote"
 	"github.com/hashicorp/terraform/terraform"
 	"github.com/mitchellh/cli"
 )
@@ -163,7 +162,7 @@ func TestInit_remoteState(t *testing.T) {
 
 	args := []string{
 		"-backend", "http",
-		"-address", conf.Config["address"],
+		"-backend-config", "address=" + conf.Config["address"],
 		testFixturePath("init"),
 		tmp,
 	}
@@ -175,9 +174,80 @@ func TestInit_remoteState(t *testing.T) {
 		t.Fatalf("err: %s", err)
 	}
 
-	path, _ := remote.HiddenStatePath()
+	if _, err := os.Stat(filepath.Join(tmp, DefaultDataDir, DefaultStateFilename)); err != nil {
-	_, err := os.Stat(path)
+		t.Fatalf("missing state: %s", err)
+	}
+}
+
+func TestInit_remoteStateWithLocal(t *testing.T) {
+	tmp, cwd := testCwd(t)
+	defer testFixCwd(t, tmp, cwd)
+
+	statePath := filepath.Join(tmp, DefaultStateFilename)
+
+	// Write some state
+	f, err := os.Create(statePath)
 	if err != nil {
-		t.Fatalf("missing state")
+		t.Fatalf("err: %s", err)
+	}
+	err = terraform.WriteState(testState(), f)
+	f.Close()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	ui := new(cli.MockUi)
+	c := &InitCommand{
+		Meta: Meta{
+			ContextOpts: testCtxConfig(testProvider()),
+			Ui:          ui,
+		},
+	}
+
+	args := []string{
+		"-backend", "http",
+		"-backend-config", "address=http://google.com",
+		testFixturePath("init"),
+	}
+	if code := c.Run(args); code == 0 {
+		t.Fatalf("should have failed: \n%s", ui.OutputWriter.String())
+	}
+}
+
+func TestInit_remoteStateWithRemote(t *testing.T) {
+	tmp, cwd := testCwd(t)
+	defer testFixCwd(t, tmp, cwd)
+
+	statePath := filepath.Join(tmp, DefaultDataDir, DefaultStateFilename)
+	if err := os.MkdirAll(filepath.Dir(statePath), 0755); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	// Write some state
+	f, err := os.Create(statePath)
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	err = terraform.WriteState(testState(), f)
+	f.Close()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	ui := new(cli.MockUi)
+	c := &InitCommand{
+		Meta: Meta{
+			ContextOpts: testCtxConfig(testProvider()),
+			Ui:          ui,
+		},
+	}
+
+	args := []string{
+		"-backend", "http",
+		"-backend-config", "address=http://google.com",
+		testFixturePath("init"),
+	}
+	if code := c.Run(args); code == 0 {
+		t.Fatalf("should have failed: \n%s", ui.OutputWriter.String())
 	}
 }

command/meta.go

@@ -5,12 +5,11 @@ import (
 	"flag"
 	"fmt"
 	"io"
-	"log"
 	"os"
 	"path/filepath"
 
 	"github.com/hashicorp/terraform/config/module"
-	"github.com/hashicorp/terraform/remote"
+	"github.com/hashicorp/terraform/state"
 	"github.com/hashicorp/terraform/terraform"
 	"github.com/mitchellh/cli"
 	"github.com/mitchellh/colorstring"
@@ -24,7 +23,8 @@ type Meta struct {
 
 	// State read when calling `Context`. This is available after calling
 	// `Context`.
-	state *terraform.State
+	state       state.State
+	stateResult *StateResult
 
 	// This can be set by the command itself to provide extra hooks.
 	extraHooks []terraform.Hook
@@ -41,24 +41,22 @@ type Meta struct {
 	color bool
 	oldUi cli.Ui
 
-	// useRemoteState is enabled if we are using remote state storage
+	// The fields below are expected to be set by the command via
-	// This is set when the context is loaded if we read from a remote
+	// command line flags. See the Apply command for an example.
-	// enabled state file.
+	//
-	useRemoteState bool
-
 	// statePath is the path to the state file. If this is empty, then
 	// no state will be loaded. It is also okay for this to be a path to
 	// a file that doesn't exist; it is assumed that this means that there
 	// is simply no state.
-	statePath string
+	//
-
 	// stateOutPath is used to override the output path for the state.
 	// If not provided, the StatePath is used causing the old state to
 	// be overriden.
-	stateOutPath string
+	//
-
 	// backupPath is used to backup the state file before writing a modified
 	// version. It defaults to stateOutPath + DefaultBackupExtention
+	statePath    string
+	stateOutPath string
 	backupPath   string
 }
 
@@ -78,11 +76,6 @@ func (m *Meta) initStatePaths() {
 
 // StateOutPath returns the true output path for the state file
 func (m *Meta) StateOutPath() string {
-	m.initStatePaths()
-	if m.useRemoteState {
-		path, _ := remote.HiddenStatePath()
-		return path
-	}
 	return m.stateOutPath
 }
 
@@ -106,14 +99,16 @@ func (m *Meta) Context(copts contextOpts) (*terraform.Context, bool, error) {
 		plan, err := terraform.ReadPlan(f)
 		f.Close()
 		if err == nil {
-			// Check if remote state is enabled, but do not refresh.
+			// Setup our state
-			// Since a plan is supposed to lock-in the changes, we do not
+			state, statePath, err := StateFromPlan(m.statePath, plan)
-			// attempt a state refresh.
+			if err != nil {
-			if plan != nil && plan.State != nil && plan.State.Remote != nil && plan.State.Remote.Type != "" {
+				return nil, false, fmt.Errorf("Error loading plan: %s", err)
-				log.Printf("[INFO] Enabling remote state from plan")
-				m.useRemoteState = true
 			}
 
+			// Set our state
+			m.state = state
+			m.stateOutPath = statePath
+
 			if len(m.variables) > 0 {
 				return nil, false, fmt.Errorf(
 					"You can't set variables with the '-var' or '-var-file' flag\n" +
@@ -132,11 +127,10 @@ func (m *Meta) Context(copts contextOpts) (*terraform.Context, bool, error) {
 	}
 
 	// Store the loaded state
-	state, err := m.loadState()
+	state, err := m.State()
 	if err != nil {
 		return nil, false, err
 	}
-	m.state = state
 
 	// Load the root module
 	mod, err := module.NewTreeModule("", copts.Path)
@@ -154,7 +148,7 @@ func (m *Meta) Context(copts contextOpts) (*terraform.Context, bool, error) {
 	}
 
 	opts.Module = mod
-	opts.State = state
+	opts.State = state.State()
 	ctx := terraform.NewContext(opts)
 	return ctx, false, nil
 }
@@ -175,6 +169,53 @@ func (m *Meta) InputMode() terraform.InputMode {
 	return mode
 }
 
+// State returns the state for this meta.
+func (m *Meta) State() (state.State, error) {
+	if m.state != nil {
+		return m.state, nil
+	}
+
+	result, err := State(m.StateOpts())
+	if err != nil {
+		return nil, err
+	}
+
+	m.state = result.State
+	m.stateOutPath = result.StatePath
+	m.stateResult = result
+	return m.state, nil
+}
+
+// StateRaw is used to setup the state manually.
+func (m *Meta) StateRaw(opts *StateOpts) (*StateResult, error) {
+	result, err := State(opts)
+	if err != nil {
+		return nil, err
+	}
+
+	m.state = result.State
+	m.stateOutPath = result.StatePath
+	m.stateResult = result
+	return result, nil
+}
+
+// StateOpts returns the default state options
+func (m *Meta) StateOpts() *StateOpts {
+	localPath := m.statePath
+	if localPath == "" {
+		localPath = DefaultStateFilename
+	}
+	remotePath := filepath.Join(DefaultDataDir, DefaultStateFilename)
+
+	return &StateOpts{
+		LocalPath:     localPath,
+		LocalPathOut:  m.stateOutPath,
+		RemotePath:    remotePath,
+		RemoteRefresh: true,
+		BackupPath:    m.backupPath,
+	}
+}
+
 // UIInput returns a UIInput object to be used for asking for input.
 func (m *Meta) UIInput() terraform.UIInput {
 	return &UIInput{
@@ -182,115 +223,14 @@ func (m *Meta) UIInput() terraform.UIInput {
 	}
 }
 
-// laodState is used to load the Terraform state. We give precedence
-// to a remote state if enabled, and then check the normal state path.
-func (m *Meta) loadState() (*terraform.State, error) {
-	// Check if we remote state is enabled
-	localCache, _, err := remote.ReadLocalState()
-	if err != nil {
-		return nil, fmt.Errorf("Error loading state: %s", err)
-	}
-
-	// Set the state if enabled
-	var state *terraform.State
-	if localCache != nil {
-		// Refresh the state
-		log.Printf("[INFO] Refreshing local state...")
-		changes, err := remote.RefreshState(localCache.Remote)
-		if err != nil {
-			return nil, fmt.Errorf("Failed to refresh state: %v", err)
-		}
-		switch changes {
-		case remote.StateChangeNoop:
-		case remote.StateChangeInit:
-		case remote.StateChangeLocalNewer:
-		case remote.StateChangeUpdateLocal:
-			// Reload the state since we've udpated
-			localCache, _, err = remote.ReadLocalState()
-			if err != nil {
-				return nil, fmt.Errorf("Error loading state: %s", err)
-			}
-		default:
-			return nil, fmt.Errorf("%s", changes)
-		}
-
-		state = localCache
-		m.useRemoteState = true
-	}
-
-	// Load up the state
-	if m.statePath != "" {
-		f, err := os.Open(m.statePath)
-		if err != nil && os.IsNotExist(err) {
-			// If the state file doesn't exist, it is okay, since it
-			// is probably a new infrastructure.
-			err = nil
-		} else if m.useRemoteState && err == nil {
-			err = fmt.Errorf("Remote state enabled, but state file '%s' also present.", m.statePath)
-			f.Close()
-		} else if err == nil {
-			state, err = terraform.ReadState(f)
-			f.Close()
-		}
-		if err != nil {
-			return nil, fmt.Errorf("Error loading state: %s", err)
-		}
-	}
-	return state, nil
-}
-
 // PersistState is used to write out the state, handling backup of
 // the existing state file and respecting path configurations.
 func (m *Meta) PersistState(s *terraform.State) error {
-	if m.useRemoteState {
+	if err := m.state.WriteState(s); err != nil {
-		return m.persistRemoteState(s)
-	}
-	return m.persistLocalState(s)
-}
-
-// persistRemoteState is used to handle persisting a state file
-// when remote state management is enabled
-func (m *Meta) persistRemoteState(s *terraform.State) error {
-	log.Printf("[INFO] Persisting state to local cache")
-	if err := remote.PersistState(s); err != nil {
 		return err
 	}
-	log.Printf("[INFO] Uploading state to remote store")
-	change, err := remote.PushState(s.Remote, false)
-	if err != nil {
-		return err
-	}
-	if !change.SuccessfulPush() {
-		return fmt.Errorf("Failed to upload state: %s", change)
-	}
-	return nil
-}
 
-// persistLocalState is used to handle persisting a state file
+	return m.state.PersistState()
-// when remote state management is disabled.
-func (m *Meta) persistLocalState(s *terraform.State) error {
-	m.initStatePaths()
-
-	// Create a backup of the state before updating
-	if m.backupPath != "-" {
-		log.Printf("[INFO] Writing backup state to: %s", m.backupPath)
-		if err := remote.CopyFile(m.statePath, m.backupPath); err != nil {
-			return fmt.Errorf("Failed to backup state: %v", err)
-		}
-	}
-
-	// Open the new state file
-	fh, err := os.Create(m.stateOutPath)
-	if err != nil {
-		return fmt.Errorf("Failed to open state file: %v", err)
-	}
-	defer fh.Close()
-
-	// Write out the state
-	if err := terraform.WriteState(s, fh); err != nil {
-		return fmt.Errorf("Failed to encode the state: %v", err)
-	}
-	return nil
 }
 
 // Input returns true if we should ask for input for context.
@@ -329,11 +269,11 @@ func (m *Meta) contextOpts() *terraform.ContextOpts {
 func (m *Meta) flagSet(n string) *flag.FlagSet {
 	f := flag.NewFlagSet(n, flag.ContinueOnError)
 	f.BoolVar(&m.input, "input", true, "input")
-	f.Var((*FlagVar)(&m.variables), "var", "variables")
+	f.Var((*FlagKV)(&m.variables), "var", "variables")
-	f.Var((*FlagVarFile)(&m.variables), "var-file", "variable file")
+	f.Var((*FlagKVFile)(&m.variables), "var-file", "variable file")
 
 	if m.autoKey != "" {
-		f.Var((*FlagVarFile)(&m.autoVariables), m.autoKey, "variable file")
+		f.Var((*FlagKVFile)(&m.autoVariables), m.autoKey, "variable file")
 	}
 
 	// Create an io.Writer that writes to our Ui properly for errors.

command/meta_test.go

@@ -7,7 +7,6 @@ import (
 	"reflect"
 	"testing"
 
-	"github.com/hashicorp/terraform/remote"
 	"github.com/hashicorp/terraform/terraform"
 )
 
@@ -182,156 +181,3 @@ func TestMeta_initStatePaths(t *testing.T) {
 		t.Fatalf("bad: %#v", m)
 	}
 }
-
-func TestMeta_persistLocal(t *testing.T) {
-	tmp, cwd := testCwd(t)
-	defer testFixCwd(t, tmp, cwd)
-
-	m := new(Meta)
-	s := terraform.NewState()
-	if err := m.persistLocalState(s); err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	exists, err := remote.ExistsFile(m.stateOutPath)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	if !exists {
-		t.Fatalf("state should exist")
-	}
-
-	// Write again, shoudl backup
-	if err := m.persistLocalState(s); err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	exists, err = remote.ExistsFile(m.backupPath)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	if !exists {
-		t.Fatalf("backup should exist")
-	}
-}
-
-func TestMeta_persistRemote(t *testing.T) {
-	tmp, cwd := testCwd(t)
-	defer testFixCwd(t, tmp, cwd)
-
-	err := remote.EnsureDirectory()
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	s := terraform.NewState()
-	conf, srv := testRemoteState(t, s, 200)
-	s.Remote = conf
-	defer srv.Close()
-
-	m := new(Meta)
-	if err := m.persistRemoteState(s); err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	local, _, err := remote.ReadLocalState()
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	if local == nil {
-		t.Fatalf("state should exist")
-	}
-
-	if err := m.persistRemoteState(s); err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	backup := remote.LocalDirectory + "/" + remote.BackupHiddenStateFile
-	exists, err := remote.ExistsFile(backup)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	if !exists {
-		t.Fatalf("backup should exist")
-	}
-}
-
-func TestMeta_loadState_remote(t *testing.T) {
-	tmp, cwd := testCwd(t)
-	defer testFixCwd(t, tmp, cwd)
-
-	err := remote.EnsureDirectory()
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	s := terraform.NewState()
-	s.Serial = 1000
-	conf, srv := testRemoteState(t, s, 200)
-	s.Remote = conf
-	defer srv.Close()
-
-	s.Serial = 500
-	if err := remote.PersistState(s); err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	m := new(Meta)
-	s1, err := m.loadState()
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	if s1.Serial < 1000 {
-		t.Fatalf("Bad: %#v", s1)
-	}
-
-	if !m.useRemoteState {
-		t.Fatalf("should enable remote")
-	}
-}
-
-func TestMeta_loadState_statePath(t *testing.T) {
-	tmp, cwd := testCwd(t)
-	defer testFixCwd(t, tmp, cwd)
-
-	m := new(Meta)
-
-	s := terraform.NewState()
-	s.Serial = 1000
-	if err := m.persistLocalState(s); err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	s1, err := m.loadState()
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	if s1.Serial < 1000 {
-		t.Fatalf("Bad: %#v", s1)
-	}
-}
-
-func TestMeta_loadState_conflict(t *testing.T) {
-	tmp, cwd := testCwd(t)
-	defer testFixCwd(t, tmp, cwd)
-
-	err := remote.EnsureDirectory()
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	m := new(Meta)
-
-	s := terraform.NewState()
-	if err := remote.PersistState(s); err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	if err := m.persistLocalState(s); err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	_, err = m.loadState()
-	if err == nil {
-		t.Fatalf("should error with conflict")
-	}
-}

command/output.go

@@ -32,12 +32,13 @@ func (c *OutputCommand) Run(args []string) int {
 	}
 	name := args[0]
 
-	state, err := c.Meta.loadState()
+	stateStore, err := c.Meta.State()
 	if err != nil {
 		c.Ui.Error(fmt.Sprintf("Error reading state: %s", err))
 		return 1
 	}
 
+	state := stateStore.State()
 	if len(state.RootModule().Outputs) == 0 {
 		c.Ui.Error(fmt.Sprintf(
 			"The state file has no outputs defined. Define an output\n" +

command/pull.go

@@ -5,7 +5,7 @@ import (
 	"fmt"
 	"strings"
 
-	"github.com/hashicorp/terraform/remote"
+	"github.com/hashicorp/terraform/state"
 )
 
 type PullCommand struct {
@@ -20,32 +20,50 @@ func (c *PullCommand) Run(args []string) int {
 		return 1
 	}
 
-	// Recover the local state if any
+	// Read out our state
-	local, _, err := remote.ReadLocalState()
+	s, err := c.State()
 	if err != nil {
-		c.Ui.Error(fmt.Sprintf("%s", err))
+		c.Ui.Error(fmt.Sprintf("Failed to read state: %s", err))
 		return 1
 	}
-	if local == nil || local.Remote == nil {
+	localState := s.State()
+
+	// If remote state isn't enabled, it is a problem.
+	if !localState.IsRemote() {
 		c.Ui.Error("Remote state not enabled!")
 		return 1
 	}
 
-	// Attempt the state refresh
+	// We need the CacheState structure in order to do anything
-	change, err := remote.RefreshState(local.Remote)
+	var cache *state.CacheState
-	if err != nil {
+	if bs, ok := s.(*state.BackupState); ok {
+		if cs, ok := bs.Real.(*state.CacheState); ok {
+			cache = cs
+		}
+	}
+	if cache == nil {
 		c.Ui.Error(fmt.Sprintf(
-			"Failed to refresh from remote state: %v", err))
+			"Failed to extract internal CacheState from remote state.\n" +
+				"This is an internal error, please report it as a bug."))
+		return 1
+	}
+
+	// Refresh the state
+	if err := cache.RefreshState(); err != nil {
+		c.Ui.Error(fmt.Sprintf(
+			"Failed to refresh from remote state: %s", err))
 		return 1
 	}
 
 	// Use an error exit code if the update was not a success
+	change := cache.RefreshResult()
 	if !change.SuccessfulPull() {
 		c.Ui.Error(fmt.Sprintf("%s", change))
 		return 1
 	} else {
 		c.Ui.Output(fmt.Sprintf("%s", change))
 	}
+
 	return 0
 }
 

command/pull_test.go

@@ -7,9 +7,10 @@ import (
 	"encoding/json"
 	"net/http"
 	"net/http/httptest"
+	"os"
+	"path/filepath"
 	"testing"
 
-	"github.com/hashicorp/terraform/remote"
 	"github.com/hashicorp/terraform/terraform"
 	"github.com/mitchellh/cli"
 )
@@ -46,10 +47,19 @@ func TestPull_local(t *testing.T) {
 	defer srv.Close()
 
 	// Store the local state
-	buf := bytes.NewBuffer(nil)
+	statePath := filepath.Join(tmp, DefaultDataDir, DefaultStateFilename)
-	terraform.WriteState(s, buf)
+	if err := os.MkdirAll(filepath.Dir(statePath), 0755); err != nil {
-	remote.EnsureDirectory()
+		t.Fatalf("err: %s", err)
-	remote.Persist(buf)
+	}
+	f, err := os.Create(statePath)
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	err = terraform.WriteState(s, f)
+	f.Close()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
 
 	ui := new(cli.MockUi)
 	c := &PullCommand{

command/push.go

@@ -5,7 +5,7 @@ import (
 	"fmt"
 	"strings"
 
-	"github.com/hashicorp/terraform/remote"
+	"github.com/hashicorp/terraform/state"
 )
 
 type PushCommand struct {
@@ -22,31 +22,52 @@ func (c *PushCommand) Run(args []string) int {
 		return 1
 	}
 
-	// Check for a remote state file
+	// Read out our state
-	local, _, err := remote.ReadLocalState()
+	s, err := c.State()
 	if err != nil {
-		c.Ui.Error(fmt.Sprintf("%s", err))
+		c.Ui.Error(fmt.Sprintf("Failed to read state: %s", err))
 		return 1
 	}
-	if local == nil || local.Remote == nil {
+	localState := s.State()
+
+	// If remote state isn't enabled, it is a problem.
+	if !localState.IsRemote() {
 		c.Ui.Error("Remote state not enabled!")
 		return 1
 	}
 
-	// Attempt to push the state
+	// We need the CacheState structure in order to do anything
-	change, err := remote.PushState(local.Remote, force)
+	var cache *state.CacheState
-	if err != nil {
+	if bs, ok := s.(*state.BackupState); ok {
-		c.Ui.Error(fmt.Sprintf("Failed to push state: %v", err))
+		if cs, ok := bs.Real.(*state.CacheState); ok {
+			cache = cs
+		}
+	}
+	if cache == nil {
+		c.Ui.Error(fmt.Sprintf(
+			"Failed to extract internal CacheState from remote state.\n" +
+				"This is an internal error, please report it as a bug."))
 		return 1
 	}
 
-	// Use an error exit code if the update was not a success
+	// Refresh the cache state
-	if !change.SuccessfulPush() {
+	if err := cache.Cache.RefreshState(); err != nil {
-		c.Ui.Error(fmt.Sprintf("%s", change))
+		c.Ui.Error(fmt.Sprintf(
+			"Failed to refresh from remote state: %s", err))
 		return 1
-	} else {
-		c.Ui.Output(fmt.Sprintf("%s", change))
 	}
+
+	// Write it to the real storage
+	remote := cache.Durable
+	if err := remote.WriteState(cache.Cache.State()); err != nil {
+		c.Ui.Error(fmt.Sprintf("Error writing state: %s", err))
+		return 1
+	}
+	if err := remote.PersistState(); err != nil {
+		c.Ui.Error(fmt.Sprintf("Error saving state: %s", err))
+		return 1
+	}
+
 	return 0
 }
 

command/push_test.go

@@ -1,10 +1,10 @@
 package command
 
 import (
-	"bytes"
+	"os"
+	"path/filepath"
 	"testing"
 
-	"github.com/hashicorp/terraform/remote"
 	"github.com/hashicorp/terraform/terraform"
 	"github.com/mitchellh/cli"
 )
@@ -41,10 +41,19 @@ func TestPush_local(t *testing.T) {
 	s.Remote = conf
 
 	// Store the local state
-	buf := bytes.NewBuffer(nil)
+	statePath := filepath.Join(tmp, DefaultDataDir, DefaultStateFilename)
-	terraform.WriteState(s, buf)
+	if err := os.MkdirAll(filepath.Dir(statePath), 0755); err != nil {
-	remote.EnsureDirectory()
+		t.Fatalf("err: %s", err)
-	remote.Persist(buf)
+	}
+	f, err := os.Create(statePath)
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	err = terraform.WriteState(s, f)
+	f.Close()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
 
 	ui := new(cli.MockUi)
 	c := &PushCommand{

command/refresh.go

@@ -5,8 +5,6 @@ import (
 	"log"
 	"os"
 	"strings"
-
-	"github.com/hashicorp/terraform/remote"
 )
 
 // RefreshCommand is a cli.Command implementation that refreshes the state
@@ -44,16 +42,16 @@ func (c *RefreshCommand) Run(args []string) int {
 	}
 
 	// Check if remote state is enabled
-	remoteEnabled, err := remote.HaveLocalState()
+	state, err := c.State()
 	if err != nil {
-		c.Ui.Error(fmt.Sprintf("Failed to check for remote state: %v", err))
+		c.Ui.Error(fmt.Sprintf("Failed to load state: %s", err))
 		return 1
 	}
 
 	// Verify that the state path exists. The "ContextArg" function below
 	// will actually do this, but we want to provide a richer error message
 	// if possible.
-	if !remoteEnabled {
+	if !state.State().IsRemote() {
 		if _, err := os.Stat(c.Meta.statePath); err != nil {
 			if os.IsNotExist(err) {
 				c.Ui.Error(fmt.Sprintf(
@@ -95,14 +93,14 @@ func (c *RefreshCommand) Run(args []string) int {
 		return 1
 	}
 
-	state, err := ctx.Refresh()
+	newState, err := ctx.Refresh()
 	if err != nil {
 		c.Ui.Error(fmt.Sprintf("Error refreshing state: %s", err))
 		return 1
 	}
 
 	log.Printf("[INFO] Writing state output to: %s", c.Meta.StateOutPath())
-	if err := c.Meta.PersistState(state); err != nil {
+	if err := c.Meta.PersistState(newState); err != nil {
 		c.Ui.Error(fmt.Sprintf("Error writing state file: %s", err))
 		return 1
 	}

command/remote.go

@@ -1,15 +1,14 @@
 package command
 
 import (
-	"bytes"
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"log"
 	"os"
 	"strings"
 
-	"github.com/hashicorp/terraform/remote"
+	"github.com/hashicorp/terraform/state"
+	"github.com/hashicorp/terraform/state/remote"
 	"github.com/hashicorp/terraform/terraform"
 )
 
@@ -32,81 +31,81 @@ type RemoteCommand struct {
 
 func (c *RemoteCommand) Run(args []string) int {
 	args = c.Meta.process(args, false)
-	var address, accessToken, name, path string
+	config := make(map[string]string)
 	cmdFlags := flag.NewFlagSet("remote", flag.ContinueOnError)
 	cmdFlags.BoolVar(&c.conf.disableRemote, "disable", false, "")
 	cmdFlags.BoolVar(&c.conf.pullOnDisable, "pull", true, "")
 	cmdFlags.StringVar(&c.conf.statePath, "state", DefaultStateFilename, "path")
 	cmdFlags.StringVar(&c.conf.backupPath, "backup", "", "path")
 	cmdFlags.StringVar(&c.remoteConf.Type, "backend", "atlas", "")
-	cmdFlags.StringVar(&address, "address", "", "")
+	cmdFlags.Var((*FlagKV)(&config), "backend-config", "config")
-	cmdFlags.StringVar(&accessToken, "access-token", "", "")
-	cmdFlags.StringVar(&name, "name", "", "")
-	cmdFlags.StringVar(&path, "path", "", "")
 	cmdFlags.Usage = func() { c.Ui.Error(c.Help()) }
 	if err := cmdFlags.Parse(args); err != nil {
 		return 1
 	}
 
 	// Show help if given no inputs
-	if !c.conf.disableRemote && c.remoteConf.Type == "atlas" &&
+	if !c.conf.disableRemote && c.remoteConf.Type == "atlas" && len(config) == 0 {
-		name == "" && accessToken == "" {
 		cmdFlags.Usage()
 		return 1
 	}
 
+	// Set the local state path
+	c.statePath = c.conf.statePath
+
 	// Populate the various configurations
-	c.remoteConf.Config = map[string]string{
+	c.remoteConf.Config = config
-		"address":      address,
-		"access_token": accessToken,
-		"name":         name,
-		"path":         path,
-	}
 
-	// Check if have an existing local state file
+	// Get the state information. We specifically request the cache only
-	haveLocal, err := remote.HaveLocalState()
+	// for the remote state here because it is possible the remote state
-	if err != nil {
+	// is invalid and we don't want to error.
-		c.Ui.Error(fmt.Sprintf("Failed to check for local state: %v", err))
+	stateOpts := c.StateOpts()
+	stateOpts.RemoteCacheOnly = true
+	if _, err := c.StateRaw(stateOpts); err != nil {
+		c.Ui.Error(fmt.Sprintf("Error loading local state: %s", err))
 		return 1
 	}
 
-	// Check if we have the non-managed state file
+	// Get the local and remote [cached] state
-	haveNonManaged, err := remote.ExistsFile(c.conf.statePath)
+	localState := c.stateResult.Local.State()
-	if err != nil {
+	var remoteState *terraform.State
-		c.Ui.Error(fmt.Sprintf("Failed to check for state file: %v", err))
+	if remote := c.stateResult.Remote; remote != nil {
-		return 1
+		remoteState = remote.State()
 	}
 
 	// Check if remote state is being disabled
 	if c.conf.disableRemote {
-		if !haveLocal {
+		if !remoteState.IsRemote() {
 			c.Ui.Error(fmt.Sprintf("Remote state management not enabled! Aborting."))
 			return 1
 		}
-		if haveNonManaged {
+		if !localState.Empty() {
 			c.Ui.Error(fmt.Sprintf("State file already exists at '%s'. Aborting.",
 				c.conf.statePath))
 			return 1
 		}
+
 		return c.disableRemoteState()
 	}
 
 	// Ensure there is no conflict
+	haveCache := !remoteState.Empty()
+	haveLocal := !localState.Empty()
 	switch {
-	case haveLocal && haveNonManaged:
+	case haveCache && haveLocal:
 		c.Ui.Error(fmt.Sprintf("Remote state is enabled, but non-managed state file '%s' is also present!",
 			c.conf.statePath))
 		return 1
 
-	case !haveLocal && !haveNonManaged:
+	case !haveCache && !haveLocal:
 		// If we don't have either state file, initialize a blank state file
 		return c.initBlankState()
 
-	case haveLocal && !haveNonManaged:
+	case haveCache && !haveLocal:
 		// Update the remote state target potentially
 		return c.updateRemoteConfig()
 
-	case !haveLocal && haveNonManaged:
+	case !haveCache && haveLocal:
 		// Enable remote state management
 		return c.enableRemoteState()
 	}
@@ -117,71 +116,66 @@ func (c *RemoteCommand) Run(args []string) int {
 // disableRemoteState is used to disable remote state management,
 // and move the state file into place.
 func (c *RemoteCommand) disableRemoteState() int {
-	// Get the local state
+	if c.stateResult == nil {
-	local, _, err := remote.ReadLocalState()
+		c.Ui.Error(fmt.Sprintf(
-	if err != nil {
+			"Internal error. State() must be called internally before remote\n" +
-		c.Ui.Error(fmt.Sprintf("Failed to read local state: %v", err))
+				"state can be disabled. Please report this as a bug."))
 		return 1
 	}
+	if !c.stateResult.State.State().IsRemote() {
+		c.Ui.Error(fmt.Sprintf(
+			"Remote state is not enabled. Can't disable remote state."))
+		return 1
+	}
+	local := c.stateResult.Local
+	remote := c.stateResult.Remote
 
 	// Ensure we have the latest state before disabling
 	if c.conf.pullOnDisable {
 		log.Printf("[INFO] Refreshing local state from remote server")
-		change, err := remote.RefreshState(local.Remote)
+		if err := remote.RefreshState(); err != nil {
-		if err != nil {
 			c.Ui.Error(fmt.Sprintf(
-				"Failed to refresh from remote state: %v", err))
+				"Failed to refresh from remote state: %s", err))
 			return 1
 		}
 
 		// Exit if we were unable to update
-		if !change.SuccessfulPull() {
+		if change := remote.RefreshResult(); !change.SuccessfulPull() {
 			c.Ui.Error(fmt.Sprintf("%s", change))
 			return 1
 		} else {
 			log.Printf("[INFO] %s", change)
 		}
-
-		// Reload the local state after the refresh
-		local, _, err = remote.ReadLocalState()
-		if err != nil {
-			c.Ui.Error(fmt.Sprintf("Failed to read local state: %v", err))
-			return 1
-		}
 	}
 
 	// Clear the remote management, and copy into place
-	local.Remote = nil
+	newState := remote.State()
-	fh, err := os.Create(c.conf.statePath)
+	newState.Remote = nil
-	if err != nil {
+	if err := local.WriteState(newState); err != nil {
-		c.Ui.Error(fmt.Sprintf("Failed to create state file '%s': %v",
+		c.Ui.Error(fmt.Sprintf("Failed to encode state file '%s': %s",
 			c.conf.statePath, err))
 		return 1
 	}
-	defer fh.Close()
+	if err := local.PersistState(); err != nil {
-	if err := terraform.WriteState(local, fh); err != nil {
+		c.Ui.Error(fmt.Sprintf("Failed to encode state file '%s': %s",
-		c.Ui.Error(fmt.Sprintf("Failed to encode state file '%s': %v",
 			c.conf.statePath, err))
 		return 1
 	}
 
 	// Remove the old state file
-	path, err := remote.HiddenStatePath()
+	if err := os.Remove(c.stateResult.RemotePath); err != nil {
-	if err != nil {
-		c.Ui.Error(fmt.Sprintf("Failed to get local state path: %v", err))
-		return 1
-	}
-	if err := os.Remove(path); err != nil {
 		c.Ui.Error(fmt.Sprintf("Failed to remove the local state file: %v", err))
 		return 1
 	}
+
 	return 0
 }
 
 // validateRemoteConfig is used to verify that the remote configuration
 // we have is valid
 func (c *RemoteCommand) validateRemoteConfig() error {
-	err := remote.ValidConfig(&c.remoteConf)
+	conf := c.remoteConf
+	_, err := remote.NewClient(conf.Type, conf.Config)
 	if err != nil {
 		c.Ui.Error(fmt.Sprintf("%s", err))
 	}
@@ -196,18 +190,17 @@ func (c *RemoteCommand) initBlankState() int {
 		return 1
 	}
 
-	// Make the hidden directory
-	if err := remote.EnsureDirectory(); err != nil {
-		c.Ui.Error(fmt.Sprintf("%s", err))
-		return 1
-	}
-
 	// Make a blank state, attach the remote configuration
 	blank := terraform.NewState()
 	blank.Remote = &c.remoteConf
 
 	// Persist the state
-	if err := remote.PersistState(blank); err != nil {
+	remote := &state.LocalState{Path: c.stateResult.RemotePath}
+	if err := remote.WriteState(blank); err != nil {
+		c.Ui.Error(fmt.Sprintf("Failed to initialize state file: %v", err))
+		return 1
+	}
+	if err := remote.PersistState(); err != nil {
 		c.Ui.Error(fmt.Sprintf("Failed to initialize state file: %v", err))
 		return 1
 	}
@@ -225,16 +218,17 @@ func (c *RemoteCommand) updateRemoteConfig() int {
 		return 1
 	}
 
-	// Read in the local state
+	// Read in the local state, which is just the cache of the remote state
-	local, _, err := remote.ReadLocalState()
+	remote := c.stateResult.Remote.Cache
-	if err != nil {
-		c.Ui.Error(fmt.Sprintf("Failed to read local state: %v", err))
-		return 1
-	}
 
 	// Update the configuration
-	local.Remote = &c.remoteConf
+	state := remote.State()
-	if err := remote.PersistState(local); err != nil {
+	state.Remote = &c.remoteConf
+	if err := remote.WriteState(state); err != nil {
+		c.Ui.Error(fmt.Sprintf("%s", err))
+		return 1
+	}
+	if err := remote.PersistState(); err != nil {
 		c.Ui.Error(fmt.Sprintf("%s", err))
 		return 1
 	}
@@ -252,21 +246,10 @@ func (c *RemoteCommand) enableRemoteState() int {
 		return 1
 	}
 
-	// Make the hidden directory
+	// Read the local state
-	if err := remote.EnsureDirectory(); err != nil {
+	local := c.stateResult.Local
-		c.Ui.Error(fmt.Sprintf("%s", err))
+	if err := local.RefreshState(); err != nil {
-		return 1
+		c.Ui.Error(fmt.Sprintf("Failed to read local state: %s", err))
-	}
-
-	// Read the provided state file
-	raw, err := ioutil.ReadFile(c.conf.statePath)
-	if err != nil {
-		c.Ui.Error(fmt.Sprintf("Failed to read '%s': %v", c.conf.statePath, err))
-		return 1
-	}
-	state, err := terraform.ReadState(bytes.NewReader(raw))
-	if err != nil {
-		c.Ui.Error(fmt.Sprintf("Failed to decode '%s': %v", c.conf.statePath, err))
 		return 1
 	}
 
@@ -279,25 +262,31 @@ func (c *RemoteCommand) enableRemoteState() int {
 		}
 
 		log.Printf("[INFO] Writing backup state to: %s", backupPath)
-		f, err := os.Create(backupPath)
+		backup := &state.LocalState{Path: backupPath}
-		if err == nil {
+		if err := backup.WriteState(local.State()); err != nil {
-			err = terraform.WriteState(state, f)
+			c.Ui.Error(fmt.Sprintf("Error writing backup state file: %s", err))
-			f.Close()
+			return 1
 		}
-		if err != nil {
+		if err := backup.PersistState(); err != nil {
 			c.Ui.Error(fmt.Sprintf("Error writing backup state file: %s", err))
 			return 1
 		}
 	}
 
 	// Update the local configuration, move into place
+	state := local.State()
 	state.Remote = &c.remoteConf
-	if err := remote.PersistState(state); err != nil {
+	remote := c.stateResult.Remote
+	if err := remote.WriteState(state); err != nil {
+		c.Ui.Error(fmt.Sprintf("%s", err))
+		return 1
+	}
+	if err := remote.PersistState(); err != nil {
 		c.Ui.Error(fmt.Sprintf("%s", err))
 		return 1
 	}
 
-	// Remove the state file
+	// Remove the original, local state file
 	log.Printf("[INFO] Removing state file: %s", c.conf.statePath)
 	if err := os.Remove(c.conf.statePath); err != nil {
 		c.Ui.Error(fmt.Sprintf("Failed to remove state file '%s': %v",
@@ -321,15 +310,12 @@ Usage: terraform remote [options]
 
 Options:
 
-  -address=url           URL of the remote storage server.
-                         Required for HTTP backend, optional for Atlas and Consul.
-
-  -access-token=token    Authentication token for state storage server.
-                         Required for Atlas backend, optional for Consul.
-
   -backend=Atlas         Specifies the type of remote backend. Must be one
                          of Atlas, Consul, or HTTP. Defaults to Atlas.
 
+  -backend-config="k=v"  Specifies configuration for the remote storage
+                         backend. This can be specified multiple times.
+
   -backup=path           Path to backup the existing state file before
                          modifying. Defaults to the "-state" path with
                          ".backup" extension. Set to "-" to disable backup.
@@ -337,12 +323,6 @@ Options:
   -disable               Disables remote state management and migrates the state
                          to the -state path.
 
-  -name=name             Name of the state file in the state storage server.
-                         Required for Atlas backend.
-
-  -path=path             Path of the remote state in Consul. Required for the
-                         Consul backend.
-
   -pull=true             Controls if the remote state is pulled before disabling.
                          This defaults to true to ensure the latest state is cached
                          before disabling.

command/remote_test.go

@@ -4,9 +4,10 @@ import (
 	"bytes"
 	"io/ioutil"
 	"os"
+	"path/filepath"
 	"testing"
 
-	"github.com/hashicorp/terraform/remote"
+	"github.com/hashicorp/terraform/state"
 	"github.com/hashicorp/terraform/terraform"
 	"github.com/mitchellh/cli"
 )
@@ -26,11 +27,15 @@ func TestRemote_disable(t *testing.T) {
 	s = terraform.NewState()
 	s.Serial = 5
 	s.Remote = conf
-	if err := remote.EnsureDirectory(); err != nil {
+
-		t.Fatalf("err: %v", err)
+	// Write the state
+	statePath := filepath.Join(tmp, DefaultDataDir, DefaultStateFilename)
+	state := &state.LocalState{Path: statePath}
+	if err := state.WriteState(s); err != nil {
+		t.Fatalf("err: %s", err)
 	}
-	if err := remote.PersistState(s); err != nil {
+	if err := state.PersistState(); err != nil {
-		t.Fatalf("err: %v", err)
+		t.Fatalf("err: %s", err)
 	}
 
 	ui := new(cli.MockUi)
@@ -45,23 +50,9 @@ func TestRemote_disable(t *testing.T) {
 		t.Fatalf("bad: \n%s", ui.ErrorWriter.String())
 	}
 
-	// Local state file should be removed
+	// Local state file should be removed and the local cache should exist
-	haveLocal, err := remote.HaveLocalState()
+	testRemoteLocal(t, true)
-	if err != nil {
+	testRemoteLocalCache(t, false)
-		t.Fatalf("err: %v", err)
-	}
-	if haveLocal {
-		t.Fatalf("should be disabled")
-	}
-
-	// New state file should be installed
-	exists, err := remote.ExistsFile(DefaultStateFilename)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	if !exists {
-		t.Fatalf("failed to make state file")
-	}
 
 	// Check that the state file was updated
 	raw, _ := ioutil.ReadFile(DefaultStateFilename)
@@ -71,11 +62,6 @@ func TestRemote_disable(t *testing.T) {
 	}
 
 	// Ensure we updated
-	// TODO: Should be 10, but WriteState currently
-	// increments incorrectly
-	if newState.Serial != 11 {
-		t.Fatalf("state file not updated: %#v", newState)
-	}
 	if newState.Remote != nil {
 		t.Fatalf("remote configuration not removed")
 	}
@@ -96,11 +82,15 @@ func TestRemote_disable_noPull(t *testing.T) {
 	s = terraform.NewState()
 	s.Serial = 5
 	s.Remote = conf
-	if err := remote.EnsureDirectory(); err != nil {
+
-		t.Fatalf("err: %v", err)
+	// Write the state
+	statePath := filepath.Join(tmp, DefaultDataDir, DefaultStateFilename)
+	state := &state.LocalState{Path: statePath}
+	if err := state.WriteState(s); err != nil {
+		t.Fatalf("err: %s", err)
 	}
-	if err := remote.PersistState(s); err != nil {
+	if err := state.PersistState(); err != nil {
-		t.Fatalf("err: %v", err)
+		t.Fatalf("err: %s", err)
 	}
 
 	ui := new(cli.MockUi)
@@ -115,23 +105,9 @@ func TestRemote_disable_noPull(t *testing.T) {
 		t.Fatalf("bad: \n%s", ui.ErrorWriter.String())
 	}
 
-	// Local state file should be removed
+	// Local state file should be removed and the local cache should exist
-	haveLocal, err := remote.HaveLocalState()
+	testRemoteLocal(t, true)
-	if err != nil {
+	testRemoteLocalCache(t, false)
-		t.Fatalf("err: %v", err)
-	}
-	if haveLocal {
-		t.Fatalf("should be disabled")
-	}
-
-	// New state file should be installed
-	exists, err := remote.ExistsFile(DefaultStateFilename)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	if !exists {
-		t.Fatalf("failed to make state file")
-	}
 
 	// Check that the state file was updated
 	raw, _ := ioutil.ReadFile(DefaultStateFilename)
@@ -140,12 +116,6 @@ func TestRemote_disable_noPull(t *testing.T) {
 		t.Fatalf("err: %v", err)
 	}
 
-	// Ensure we DIDNT updated
-	// TODO: Should be 5, but WriteState currently increments
-	// this which is incorrect.
-	if newState.Serial != 7 {
-		t.Fatalf("state file updated: %#v", newState)
-	}
 	if newState.Remote != nil {
 		t.Fatalf("remote configuration not removed")
 	}
@@ -178,11 +148,15 @@ func TestRemote_disable_otherState(t *testing.T) {
 	// Persist local remote state
 	s := terraform.NewState()
 	s.Serial = 5
-	if err := remote.EnsureDirectory(); err != nil {
+
-		t.Fatalf("err: %v", err)
+	// Write the state
+	statePath := filepath.Join(tmp, DefaultDataDir, DefaultStateFilename)
+	state := &state.LocalState{Path: statePath}
+	if err := state.WriteState(s); err != nil {
+		t.Fatalf("err: %s", err)
 	}
-	if err := remote.PersistState(s); err != nil {
+	if err := state.PersistState(); err != nil {
-		t.Fatalf("err: %v", err)
+		t.Fatalf("err: %s", err)
 	}
 
 	// Also put a file at the default path
@@ -218,11 +192,15 @@ func TestRemote_managedAndNonManaged(t *testing.T) {
 	// Persist local remote state
 	s := terraform.NewState()
 	s.Serial = 5
-	if err := remote.EnsureDirectory(); err != nil {
+
-		t.Fatalf("err: %v", err)
+	// Write the state
+	statePath := filepath.Join(tmp, DefaultDataDir, DefaultStateFilename)
+	state := &state.LocalState{Path: statePath}
+	if err := state.WriteState(s); err != nil {
+		t.Fatalf("err: %s", err)
 	}
-	if err := remote.PersistState(s); err != nil {
+	if err := state.PersistState(); err != nil {
-		t.Fatalf("err: %v", err)
+		t.Fatalf("err: %s", err)
 	}
 
 	// Also put a file at the default path
@@ -265,18 +243,20 @@ func TestRemote_initBlank(t *testing.T) {
 
 	args := []string{
 		"-backend=http",
-		"-address", "http://example.com",
+		"-backend-config", "address=http://example.com",
-		"-access-token=test",
+		"-backend-config", "access_token=test",
 	}
 	if code := c.Run(args); code != 0 {
 		t.Fatalf("bad: \n%s", ui.ErrorWriter.String())
 	}
 
-	local, _, err := remote.ReadLocalState()
+	remotePath := filepath.Join(DefaultDataDir, DefaultStateFilename)
-	if err != nil {
+	ls := &state.LocalState{Path: remotePath}
-		t.Fatalf("err: %v", err)
+	if err := ls.RefreshState(); err != nil {
+		t.Fatalf("err: %s", err)
 	}
 
+	local := ls.State()
 	if local.Remote.Type != "http" {
 		t.Fatalf("Bad: %#v", local.Remote)
 	}
@@ -318,11 +298,15 @@ func TestRemote_updateRemote(t *testing.T) {
 	s.Remote = &terraform.RemoteState{
 		Type: "invalid",
 	}
-	if err := remote.EnsureDirectory(); err != nil {
+
-		t.Fatalf("err: %v", err)
+	// Write the state
+	statePath := filepath.Join(tmp, DefaultDataDir, DefaultStateFilename)
+	ls := &state.LocalState{Path: statePath}
+	if err := ls.WriteState(s); err != nil {
+		t.Fatalf("err: %s", err)
 	}
-	if err := remote.PersistState(s); err != nil {
+	if err := ls.PersistState(); err != nil {
-		t.Fatalf("err: %v", err)
+		t.Fatalf("err: %s", err)
 	}
 
 	ui := new(cli.MockUi)
@@ -335,18 +319,19 @@ func TestRemote_updateRemote(t *testing.T) {
 
 	args := []string{
 		"-backend=http",
-		"-address",
+		"-backend-config", "address=http://example.com",
-		"http://example.com",
+		"-backend-config", "access_token=test",
-		"-access-token=test",
 	}
 	if code := c.Run(args); code != 0 {
 		t.Fatalf("bad: \n%s", ui.ErrorWriter.String())
 	}
 
-	local, _, err := remote.ReadLocalState()
+	remotePath := filepath.Join(DefaultDataDir, DefaultStateFilename)
-	if err != nil {
+	ls = &state.LocalState{Path: remotePath}
-		t.Fatalf("err: %v", err)
+	if err := ls.RefreshState(); err != nil {
+		t.Fatalf("err: %s", err)
 	}
+	local := ls.State()
 
 	if local.Remote.Type != "http" {
 		t.Fatalf("Bad: %#v", local.Remote)
@@ -389,18 +374,19 @@ func TestRemote_enableRemote(t *testing.T) {
 
 	args := []string{
 		"-backend=http",
-		"-address",
+		"-backend-config", "address=http://example.com",
-		"http://example.com",
+		"-backend-config", "access_token=test",
-		"-access-token=test",
 	}
 	if code := c.Run(args); code != 0 {
 		t.Fatalf("bad: \n%s", ui.ErrorWriter.String())
 	}
 
-	local, _, err := remote.ReadLocalState()
+	remotePath := filepath.Join(DefaultDataDir, DefaultStateFilename)
-	if err != nil {
+	ls := &state.LocalState{Path: remotePath}
-		t.Fatalf("err: %v", err)
+	if err := ls.RefreshState(); err != nil {
+		t.Fatalf("err: %s", err)
 	}
+	local := ls.State()
 
 	if local.Remote.Type != "http" {
 		t.Fatalf("Bad: %#v", local.Remote)
@@ -412,21 +398,49 @@ func TestRemote_enableRemote(t *testing.T) {
 		t.Fatalf("Bad: %#v", local.Remote)
 	}
 
-	// Backup file should exist
+	// Backup file should exist, state file should not
-	exist, err := remote.ExistsFile(DefaultStateFilename + DefaultBackupExtention)
+	testRemoteLocal(t, false)
-	if err != nil {
+	testRemoteLocalBackup(t, true)
-		t.Fatalf("err: %v", err)
-	}
-	if !exist {
-		t.Fatalf("backup should exist")
 }
 
-	// State file should not
+func testRemoteLocal(t *testing.T, exists bool) {
-	exist, err = remote.ExistsFile(DefaultStateFilename)
+	_, err := os.Stat(DefaultStateFilename)
-	if err != nil {
+	if os.IsNotExist(err) && !exists {
-		t.Fatalf("err: %v", err)
+		return
 	}
-	if exist {
+	if err == nil && exists {
-		t.Fatalf("state file should not exist")
+		return
 	}
+
+	t.Fatalf("bad: %#v", err)
+}
+
+func testRemoteLocalBackup(t *testing.T, exists bool) {
+	_, err := os.Stat(DefaultStateFilename + DefaultBackupExtention)
+	if os.IsNotExist(err) && !exists {
+		return
+	}
+	if err == nil && exists {
+		return
+	}
+	if err == nil && !exists {
+		t.Fatal("expected local backup to exist")
+	}
+
+	t.Fatalf("bad: %#v", err)
+}
+
+func testRemoteLocalCache(t *testing.T, exists bool) {
+	_, err := os.Stat(filepath.Join(DefaultDataDir, DefaultStateFilename))
+	if os.IsNotExist(err) && !exists {
+		return
+	}
+	if err == nil && exists {
+		return
+	}
+	if err == nil && !exists {
+		t.Fatal("expected local cache to exist")
+	}
+
+	t.Fatalf("bad: %#v", err)
 }

command/show.go

@@ -6,6 +6,7 @@ import (
 	"os"
 	"strings"
 
+	statelib "github.com/hashicorp/terraform/state"
 	"github.com/hashicorp/terraform/terraform"
 )
 
@@ -36,7 +37,7 @@ func (c *ShowCommand) Run(args []string) int {
 		return 1
 	}
 
-	var err, planErr, stateErr error
+	var planErr, stateErr error
 	var path string
 	var plan *terraform.Plan
 	var state *terraform.State
@@ -68,12 +69,13 @@ func (c *ShowCommand) Run(args []string) int {
 
 	} else {
 		// We should use the default state if it exists.
-		c.Meta.statePath = DefaultStateFilename
+		stateStore := &statelib.LocalState{Path: DefaultStateFilename}
-		state, err = c.Meta.loadState()
+		if err := stateStore.RefreshState(); err != nil {
-		if err != nil {
 			c.Ui.Error(fmt.Sprintf("Error reading state: %s", err))
 			return 1
 		}
+
+		state = stateStore.State()
 		if state == nil {
 			c.Ui.Output("No state.")
 			return 0

command/state.go

@@ -0,0 +1,263 @@
+package command
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/hashicorp/errwrap"
+	"github.com/hashicorp/terraform/state"
+	"github.com/hashicorp/terraform/state/remote"
+	"github.com/hashicorp/terraform/terraform"
+)
+
+// StateOpts are options to get the state for a command.
+type StateOpts struct {
+	// LocalPath is the path where the state is stored locally.
+	//
+	// LocalPathOut is the path where the local state will be saved. If this
+	// isn't set, it will be saved back to LocalPath.
+	LocalPath    string
+	LocalPathOut string
+
+	// RemotePath is the path where the remote state cache would be.
+	//
+	// RemoteCache, if true, will set the result to only be the cache
+	// and not backed by any real durable storage.
+	RemotePath      string
+	RemoteCacheOnly bool
+	RemoteRefresh   bool
+
+	// BackupPath is the path where the backup will be placed. If not set,
+	// it is assumed to be the path where the state is stored locally
+	// plus the DefaultBackupExtension.
+	BackupPath string
+}
+
+// StateResult is the result of calling State and holds various different
+// State implementations so they can be accessed directly.
+type StateResult struct {
+	// State is the final outer state that should be used for all
+	// _real_ reads/writes.
+	//
+	// StatePath is the local path where the state will be stored or
+	// cached, no matter whether State is local or remote.
+	State     state.State
+	StatePath string
+
+	// Local and Remote are the local/remote state implementations, raw
+	// and unwrapped by any backups. The paths here are the paths where
+	// these state files would be saved.
+	Local      *state.LocalState
+	LocalPath  string
+	Remote     *state.CacheState
+	RemotePath string
+}
+
+// State returns the proper state.State implementation to represent the
+// current environment.
+//
+// localPath is the path to where state would be if stored locally.
+// dataDir is the path to the local data directory where the remote state
+// cache would be stored.
+func State(opts *StateOpts) (*StateResult, error) {
+	result := new(StateResult)
+
+	// Get the remote state cache path
+	if opts.RemotePath != "" {
+		result.RemotePath = opts.RemotePath
+
+		var remote *state.CacheState
+		if opts.RemoteCacheOnly {
+			// Setup the in-memory state
+			ls := &state.LocalState{Path: opts.RemotePath}
+			if err := ls.RefreshState(); err != nil {
+				return nil, err
+			}
+			is := &state.InmemState{}
+			is.WriteState(ls.State())
+
+			// Setupt he remote state, cache-only, and refresh it so that
+			// we have access to the state right away.
+			remote = &state.CacheState{
+				Cache:   ls,
+				Durable: is,
+			}
+			if err := remote.RefreshState(); err != nil {
+				return nil, err
+			}
+		} else {
+			if _, err := os.Stat(opts.RemotePath); err == nil {
+				// We have a remote state, initialize that.
+				remote, err = remoteStateFromPath(
+					opts.RemotePath,
+					opts.RemoteRefresh)
+				if err != nil {
+					return nil, err
+				}
+			}
+		}
+
+		if remote != nil {
+			result.State = remote
+			result.StatePath = opts.RemotePath
+			result.Remote = remote
+		}
+	}
+
+	// Do we have a local state?
+	if opts.LocalPath != "" {
+		local := &state.LocalState{
+			Path:    opts.LocalPath,
+			PathOut: opts.LocalPathOut,
+		}
+
+		// Always store it in the result even if we're not using it
+		result.Local = local
+		result.LocalPath = local.Path
+		if local.PathOut != "" {
+			result.LocalPath = local.PathOut
+		}
+
+		err := local.RefreshState()
+		if err == nil {
+			if result.State != nil && !result.State.State().Empty() {
+				if !local.State().Empty() {
+					// We already have a remote state... that is an error.
+					return nil, fmt.Errorf(
+						"Remote state found, but state file '%s' also present.",
+						opts.LocalPath)
+				}
+
+				// Empty state
+				local = nil
+			}
+		}
+		if err != nil {
+			return nil, errwrap.Wrapf(
+				"Error reading local state: {{err}}", err)
+		}
+
+		if local != nil {
+			result.State = local
+			result.StatePath = opts.LocalPath
+			if opts.LocalPathOut != "" {
+				result.StatePath = opts.LocalPathOut
+			}
+		}
+	}
+
+	// If we have a result, make sure to back it up
+	if result.State != nil {
+		backupPath := result.StatePath + DefaultBackupExtention
+		if opts.BackupPath != "" {
+			backupPath = opts.BackupPath
+		}
+
+		result.State = &state.BackupState{
+			Real: result.State,
+			Path: backupPath,
+		}
+	}
+
+	// Return whatever state we have
+	return result, nil
+}
+
+// StateFromPlan gets our state from the plan.
+func StateFromPlan(
+	localPath string, plan *terraform.Plan) (state.State, string, error) {
+	var result state.State
+	resultPath := localPath
+	if plan != nil && plan.State != nil &&
+		plan.State.Remote != nil && plan.State.Remote.Type != "" {
+		var err error
+
+		// It looks like we have a remote state in the plan, so
+		// we have to initialize that.
+		resultPath = filepath.Join(DefaultDataDir, DefaultStateFilename)
+		result, err = remoteState(plan.State, resultPath, false)
+		if err != nil {
+			return nil, "", err
+		}
+	}
+
+	if result == nil {
+		local := &state.LocalState{Path: resultPath}
+		local.SetState(plan.State)
+		result = local
+	}
+
+	// If we have a result, make sure to back it up
+	result = &state.BackupState{
+		Real: result,
+		Path: resultPath + DefaultBackupExtention,
+	}
+
+	return result, resultPath, nil
+}
+
+func remoteState(
+	local *terraform.State,
+	localPath string, refresh bool) (*state.CacheState, error) {
+	// If there is no remote settings, it is an error
+	if local.Remote == nil {
+		return nil, fmt.Errorf("Remote state cache has no remote info")
+	}
+
+	// Initialize the remote client based on the local state
+	client, err := remote.NewClient(local.Remote.Type, local.Remote.Config)
+	if err != nil {
+		return nil, errwrap.Wrapf(fmt.Sprintf(
+			"Error initializing remote driver '%s': {{err}}",
+			local.Remote.Type), err)
+	}
+
+	// Create the remote client
+	durable := &remote.State{Client: client}
+
+	// Create the cached client
+	cache := &state.CacheState{
+		Cache:   &state.LocalState{Path: localPath},
+		Durable: durable,
+	}
+
+	if refresh {
+		// Refresh the cache
+		if err := cache.RefreshState(); err != nil {
+			return nil, errwrap.Wrapf(
+				"Error reloading remote state: {{err}}", err)
+		}
+		switch cache.RefreshResult() {
+		case state.CacheRefreshNoop:
+		case state.CacheRefreshInit:
+		case state.CacheRefreshLocalNewer:
+		case state.CacheRefreshUpdateLocal:
+			// Write our local state out to the durable storage to start.
+			if err := cache.WriteState(local); err != nil {
+				return nil, errwrap.Wrapf(
+					"Error preparing remote state: {{err}}", err)
+			}
+			if err := cache.PersistState(); err != nil {
+				return nil, errwrap.Wrapf(
+					"Error preparing remote state: {{err}}", err)
+			}
+		default:
+			return nil, errwrap.Wrapf(
+				"Error initilizing remote state: {{err}}", err)
+		}
+	}
+
+	return cache, nil
+}
+
+func remoteStateFromPath(path string, refresh bool) (*state.CacheState, error) {
+	// First create the local state for the path
+	local := &state.LocalState{Path: path}
+	if err := local.RefreshState(); err != nil {
+		return nil, err
+	}
+	localState := local.State()
+
+	return remoteState(localState, path, refresh)
+}

commands.go

@@ -14,8 +14,10 @@ var Commands map[string]cli.CommandFactory
 // Ui is the cli.Ui used for communicating to the outside world.
 var Ui cli.Ui
 
-const ErrorPrefix = "e:"
+const (
-const OutputPrefix = "o:"
+	ErrorPrefix  = "e:"
+	OutputPrefix = "o:"
+)
 
 func init() {
 	Ui = &cli.PrefixedUi{

remote/atlas_test.go

@@ -1,128 +0,0 @@
-package remote
-
-import (
-	"bytes"
-	"crypto/md5"
-	"os"
-	"testing"
-
-	"github.com/hashicorp/terraform/terraform"
-)
-
-func TestAtlasRemote_Interface(t *testing.T) {
-	var client interface{} = &AtlasRemoteClient{}
-	if _, ok := client.(RemoteClient); !ok {
-		t.Fatalf("does not implement interface")
-	}
-}
-
-func checkAtlas(t *testing.T) {
-	if os.Getenv("ATLAS_TOKEN") == "" {
-		t.SkipNow()
-	}
-}
-
-func TestAtlasRemote_Validate(t *testing.T) {
-	conf := map[string]string{}
-	if _, err := NewAtlasRemoteClient(conf); err == nil {
-		t.Fatalf("expect error")
-	}
-
-	conf["access_token"] = "test"
-	conf["name"] = "hashicorp/test-state"
-	if _, err := NewAtlasRemoteClient(conf); err != nil {
-		t.Fatalf("err: %v", err)
-	}
-}
-
-func TestAtlasRemote_Validate_envVar(t *testing.T) {
-	conf := map[string]string{}
-	if _, err := NewAtlasRemoteClient(conf); err == nil {
-		t.Fatalf("expect error")
-	}
-
-	defer os.Setenv("ATLAS_TOKEN", os.Getenv("ATLAS_TOKEN"))
-	os.Setenv("ATLAS_TOKEN", "foo")
-
-	conf["name"] = "hashicorp/test-state"
-	if _, err := NewAtlasRemoteClient(conf); err != nil {
-		t.Fatalf("err: %v", err)
-	}
-}
-
-func TestAtlasRemote(t *testing.T) {
-	checkAtlas(t)
-	remote := &terraform.RemoteState{
-		Type: "atlas",
-		Config: map[string]string{
-			"access_token": os.Getenv("ATLAS_TOKEN"),
-			"name":         "hashicorp/test-remote-state",
-		},
-	}
-	r, err := NewClientByState(remote)
-	if err != nil {
-		t.Fatalf("Err: %v", err)
-	}
-
-	// Get a valid input
-	inp, err := blankState(remote)
-	if err != nil {
-		t.Fatalf("Err: %v", err)
-	}
-	inpMD5 := md5.Sum(inp)
-	hash := inpMD5[:16]
-
-	// Delete the state, should be none
-	err = r.DeleteState()
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	// Ensure no state
-	payload, err := r.GetState()
-	if err != nil {
-		t.Fatalf("Err: %v", err)
-	}
-	if payload != nil {
-		t.Fatalf("unexpected payload")
-	}
-
-	// Put the state
-	err = r.PutState(inp, false)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	// Get it back
-	payload, err = r.GetState()
-	if err != nil {
-		t.Fatalf("Err: %v", err)
-	}
-	if payload == nil {
-		t.Fatalf("unexpected payload")
-	}
-
-	// Check the payload
-	if !bytes.Equal(payload.MD5, hash) {
-		t.Fatalf("bad hash: %x %x", payload.MD5, hash)
-	}
-	if !bytes.Equal(payload.State, inp) {
-		t.Errorf("inp: %s", inp)
-		t.Fatalf("bad response: %s", payload.State)
-	}
-
-	// Delete the state
-	err = r.DeleteState()
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	// Should be gone
-	payload, err = r.GetState()
-	if err != nil {
-		t.Fatalf("Err: %v", err)
-	}
-	if payload != nil {
-		t.Fatalf("unexpected payload")
-	}
-}

remote/client.go

@@ -1,65 +0,0 @@
-package remote
-
-import (
-	"fmt"
-	"strings"
-
-	"github.com/hashicorp/terraform/terraform"
-)
-
-var (
-	// ErrConflict is used to indicate the upload was rejected
-	// due to a conflict on the state
-	ErrConflict = fmt.Errorf("Conflicting state file")
-
-	// ErrServerNewer is used to indicate the serial number of
-	// the state is newer on the server side
-	ErrServerNewer = fmt.Errorf("Server-side Serial is newer")
-
-	// ErrRequireAuth is used if the remote server requires
-	// authentication and none is provided
-	ErrRequireAuth = fmt.Errorf("Remote server requires authentication")
-
-	// ErrInvalidAuth is used if we provide authentication which
-	// is not valid
-	ErrInvalidAuth = fmt.Errorf("Invalid authentication")
-
-	// ErrRemoteInternal is used if we get an internal error
-	// from the remote server
-	ErrRemoteInternal = fmt.Errorf("Remote server reporting internal error")
-)
-
-type RemoteClient interface {
-	GetState() (*RemoteStatePayload, error)
-	PutState(state []byte, force bool) error
-	DeleteState() error
-}
-
-// RemoteStatePayload is used to return the remote state
-// along with associated meta data when we do a remote fetch.
-type RemoteStatePayload struct {
-	MD5   []byte
-	State []byte
-}
-
-// NewClientByState is used to construct a client from
-// our remote state.
-func NewClientByState(remote *terraform.RemoteState) (RemoteClient, error) {
-	return NewClientByType(remote.Type, remote.Config)
-}
-
-// NewClientByType is used to construct a RemoteClient
-// based on the configured type.
-func NewClientByType(ctype string, conf map[string]string) (RemoteClient, error) {
-	ctype = strings.ToLower(ctype)
-	switch ctype {
-	case "atlas":
-		return NewAtlasRemoteClient(conf)
-	case "consul":
-		return NewConsulRemoteClient(conf)
-	case "http":
-		return NewHTTPRemoteClient(conf)
-	default:
-		return nil, fmt.Errorf("Unknown remote client type '%s'", ctype)
-	}
-}

remote/client_test.go

@@ -1 +0,0 @@
-package remote

remote/consul.go

@@ -1,77 +0,0 @@
-package remote
-
-import (
-	"crypto/md5"
-	"fmt"
-
-	consulapi "github.com/hashicorp/consul/api"
-)
-
-// ConsulRemoteClient implements the RemoteClient interface
-// for an Consul compatible server.
-type ConsulRemoteClient struct {
-	client *consulapi.Client
-	path   string // KV path
-}
-
-func NewConsulRemoteClient(conf map[string]string) (*ConsulRemoteClient, error) {
-	client := &ConsulRemoteClient{}
-	if err := client.validateConfig(conf); err != nil {
-		return nil, err
-	}
-	return client, nil
-}
-
-func (c *ConsulRemoteClient) validateConfig(conf map[string]string) (err error) {
-	config := consulapi.DefaultConfig()
-	if token, ok := conf["access_token"]; ok && token != "" {
-		config.Token = token
-	}
-	if addr, ok := conf["address"]; ok && addr != "" {
-		config.Address = addr
-	}
-	path, ok := conf["path"]
-	if !ok || path == "" {
-		return fmt.Errorf("missing 'path' configuration")
-	}
-	c.path = path
-	c.client, err = consulapi.NewClient(config)
-	return err
-}
-
-func (c *ConsulRemoteClient) GetState() (*RemoteStatePayload, error) {
-	kv := c.client.KV()
-	pair, _, err := kv.Get(c.path, nil)
-	if err != nil {
-		return nil, err
-	}
-	if pair == nil {
-		return nil, nil
-	}
-
-	// Create the payload
-	payload := &RemoteStatePayload{
-		State: pair.Value,
-	}
-
-	// Generate the MD5
-	hash := md5.Sum(payload.State)
-	payload.MD5 = hash[:md5.Size]
-	return payload, nil
-}
-
-func (c *ConsulRemoteClient) PutState(state []byte, force bool) error {
-	pair := &consulapi.KVPair{
-		Key:   c.path,
-		Value: state,
-	}
-	kv := c.client.KV()
-	_, err := kv.Put(pair, nil)
-	return err
-}
-
-func (c *ConsulRemoteClient) DeleteState() error {
-	kv := c.client.KV()
-	_, err := kv.Delete(c.path, nil)
-	return err
-}

remote/consul_test.go

@@ -1,173 +0,0 @@
-package remote
-
-import (
-	"bytes"
-	"crypto/md5"
-	"os"
-	"testing"
-
-	consulapi "github.com/hashicorp/consul/api"
-	"github.com/hashicorp/terraform/terraform"
-)
-
-func TestConsulRemote_Interface(t *testing.T) {
-	var client interface{} = &ConsulRemoteClient{}
-	if _, ok := client.(RemoteClient); !ok {
-		t.Fatalf("does not implement interface")
-	}
-}
-
-func checkConsul(t *testing.T) {
-	if os.Getenv("CONSUL_ADDR") == "" {
-		t.SkipNow()
-	}
-}
-
-func TestConsulRemote_Validate(t *testing.T) {
-	conf := map[string]string{}
-	if _, err := NewConsulRemoteClient(conf); err == nil {
-		t.Fatalf("expect error")
-	}
-
-	conf["path"] = "test"
-	if _, err := NewConsulRemoteClient(conf); err != nil {
-		t.Fatalf("err: %v", err)
-	}
-}
-
-func TestConsulRemote_GetState(t *testing.T) {
-	checkConsul(t)
-	type tcase struct {
-		Path      string
-		Body      []byte
-		ExpectMD5 []byte
-		ExpectErr string
-	}
-	inp := []byte("testing")
-	inpMD5 := md5.Sum(inp)
-	hash := inpMD5[:16]
-	cases := []*tcase{
-		&tcase{
-			Path:      "foo",
-			Body:      inp,
-			ExpectMD5: hash,
-		},
-		&tcase{
-			Path: "none",
-		},
-	}
-
-	for _, tc := range cases {
-		if tc.Body != nil {
-			conf := consulapi.DefaultConfig()
-			conf.Address = os.Getenv("CONSUL_ADDR")
-			client, _ := consulapi.NewClient(conf)
-			pair := &consulapi.KVPair{Key: tc.Path, Value: tc.Body}
-			client.KV().Put(pair, nil)
-		}
-
-		remote := &terraform.RemoteState{
-			Type: "consul",
-			Config: map[string]string{
-				"address": os.Getenv("CONSUL_ADDR"),
-				"path":    tc.Path,
-			},
-		}
-		r, err := NewClientByState(remote)
-		if err != nil {
-			t.Fatalf("Err: %v", err)
-		}
-
-		payload, err := r.GetState()
-		errStr := ""
-		if err != nil {
-			errStr = err.Error()
-		}
-		if errStr != tc.ExpectErr {
-			t.Fatalf("bad err: %v %v", errStr, tc.ExpectErr)
-		}
-
-		if tc.ExpectMD5 != nil {
-			if payload == nil || !bytes.Equal(payload.MD5, tc.ExpectMD5) {
-				t.Fatalf("bad: %#v", payload)
-			}
-		}
-
-		if tc.Body != nil {
-			if !bytes.Equal(payload.State, tc.Body) {
-				t.Fatalf("bad: %#v", payload)
-			}
-		}
-	}
-}
-
-func TestConsulRemote_PutState(t *testing.T) {
-	checkConsul(t)
-	path := "foobar"
-	inp := []byte("testing")
-
-	remote := &terraform.RemoteState{
-		Type: "consul",
-		Config: map[string]string{
-			"address": os.Getenv("CONSUL_ADDR"),
-			"path":    path,
-		},
-	}
-	r, err := NewClientByState(remote)
-	if err != nil {
-		t.Fatalf("Err: %v", err)
-	}
-
-	err = r.PutState(inp, false)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	conf := consulapi.DefaultConfig()
-	conf.Address = os.Getenv("CONSUL_ADDR")
-	client, _ := consulapi.NewClient(conf)
-	pair, _, err := client.KV().Get(path, nil)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	if !bytes.Equal(pair.Value, inp) {
-		t.Fatalf("bad value")
-	}
-}
-
-func TestConsulRemote_DeleteState(t *testing.T) {
-	checkConsul(t)
-	path := "testdelete"
-
-	// Create the state
-	conf := consulapi.DefaultConfig()
-	conf.Address = os.Getenv("CONSUL_ADDR")
-	client, _ := consulapi.NewClient(conf)
-	pair := &consulapi.KVPair{Key: path, Value: []byte("test")}
-	client.KV().Put(pair, nil)
-
-	remote := &terraform.RemoteState{
-		Type: "consul",
-		Config: map[string]string{
-			"address": os.Getenv("CONSUL_ADDR"),
-			"path":    path,
-		},
-	}
-	r, err := NewClientByState(remote)
-	if err != nil {
-		t.Fatalf("Err: %v", err)
-	}
-
-	err = r.DeleteState()
-	if err != nil {
-		t.Fatalf("Err: %v", err)
-	}
-
-	pair, _, err = client.KV().Get(path, nil)
-	if err != nil {
-		t.Fatalf("Err: %v", err)
-	}
-	if pair != nil {
-		t.Fatalf("state not deleted")
-	}
-}

remote/http.go

@@ -1,182 +0,0 @@
-package remote
-
-import (
-	"bytes"
-	"crypto/md5"
-	"encoding/base64"
-	"fmt"
-	"io"
-	"net/http"
-	"net/url"
-)
-
-// HTTPRemoteClient implements the RemoteClient interface
-// for an HTTP compatible server.
-type HTTPRemoteClient struct {
-	// url is the URL that we GET / POST / DELETE to
-	url *url.URL
-}
-
-func NewHTTPRemoteClient(conf map[string]string) (*HTTPRemoteClient, error) {
-	client := &HTTPRemoteClient{}
-	if err := client.validateConfig(conf); err != nil {
-		return nil, err
-	}
-	return client, nil
-}
-
-func (c *HTTPRemoteClient) validateConfig(conf map[string]string) error {
-	urlRaw, ok := conf["address"]
-	if !ok || urlRaw == "" {
-		return fmt.Errorf("missing 'address' configuration")
-	}
-	url, err := url.Parse(urlRaw)
-	if err != nil {
-		return fmt.Errorf("failed to parse url: %v", err)
-	}
-	if url.Scheme != "http" && url.Scheme != "https" {
-		return fmt.Errorf("invalid url: %s", url)
-	}
-	c.url = url
-	return nil
-}
-
-func (c *HTTPRemoteClient) GetState() (*RemoteStatePayload, error) {
-	// Request the url
-	resp, err := http.Get(c.url.String())
-	if err != nil {
-		return nil, err
-	}
-	defer resp.Body.Close()
-
-	// Handle the common status codes
-	switch resp.StatusCode {
-	case http.StatusOK:
-		// Handled after
-	case http.StatusNoContent:
-		return nil, nil
-	case http.StatusNotFound:
-		return nil, nil
-	case http.StatusUnauthorized:
-		return nil, ErrRequireAuth
-	case http.StatusForbidden:
-		return nil, ErrInvalidAuth
-	case http.StatusInternalServerError:
-		return nil, ErrRemoteInternal
-	default:
-		return nil, fmt.Errorf("Unexpected HTTP response code %d", resp.StatusCode)
-	}
-
-	// Read in the body
-	buf := bytes.NewBuffer(nil)
-	if _, err := io.Copy(buf, resp.Body); err != nil {
-		return nil, fmt.Errorf("Failed to read remote state: %v", err)
-	}
-
-	// Create the payload
-	payload := &RemoteStatePayload{
-		State: buf.Bytes(),
-	}
-
-	// Check for the MD5
-	if raw := resp.Header.Get("Content-MD5"); raw != "" {
-		md5, err := base64.StdEncoding.DecodeString(raw)
-		if err != nil {
-			return nil, fmt.Errorf("Failed to decode Content-MD5 '%s': %v", raw, err)
-		}
-		payload.MD5 = md5
-
-	} else {
-		// Generate the MD5
-		hash := md5.Sum(payload.State)
-		payload.MD5 = hash[:md5.Size]
-	}
-
-	return payload, nil
-}
-
-func (c *HTTPRemoteClient) PutState(state []byte, force bool) error {
-	// Copy the target URL
-	base := new(url.URL)
-	*base = *c.url
-
-	// Generate the MD5
-	hash := md5.Sum(state)
-	b64 := base64.StdEncoding.EncodeToString(hash[:md5.Size])
-
-	// Set the force query parameter if needed
-	if force {
-		values := base.Query()
-		values.Set("force", "true")
-		base.RawQuery = values.Encode()
-	}
-
-	// Make the HTTP client and request
-	req, err := http.NewRequest("POST", base.String(), bytes.NewReader(state))
-	if err != nil {
-		return fmt.Errorf("Failed to make HTTP request: %v", err)
-	}
-
-	// Prepare the request
-	req.Header.Set("Content-Type", "application/octet-stream")
-	req.Header.Set("Content-MD5", b64)
-	req.ContentLength = int64(len(state))
-
-	// Make the request
-	resp, err := http.DefaultClient.Do(req)
-	if err != nil {
-		return fmt.Errorf("Failed to upload state: %v", err)
-	}
-	defer resp.Body.Close()
-
-	// Handle the error codes
-	switch resp.StatusCode {
-	case http.StatusOK:
-		return nil
-	case http.StatusConflict:
-		return ErrConflict
-	case http.StatusPreconditionFailed:
-		return ErrServerNewer
-	case http.StatusUnauthorized:
-		return ErrRequireAuth
-	case http.StatusForbidden:
-		return ErrInvalidAuth
-	case http.StatusInternalServerError:
-		return ErrRemoteInternal
-	default:
-		return fmt.Errorf("Unexpected HTTP response code %d", resp.StatusCode)
-	}
-}
-
-func (c *HTTPRemoteClient) DeleteState() error {
-	// Make the HTTP request
-	req, err := http.NewRequest("DELETE", c.url.String(), nil)
-	if err != nil {
-		return fmt.Errorf("Failed to make HTTP request: %v", err)
-	}
-
-	// Make the request
-	resp, err := http.DefaultClient.Do(req)
-	if err != nil {
-		return fmt.Errorf("Failed to delete state: %v", err)
-	}
-	defer resp.Body.Close()
-
-	// Handle the error codes
-	switch resp.StatusCode {
-	case http.StatusOK:
-		return nil
-	case http.StatusNoContent:
-		return nil
-	case http.StatusNotFound:
-		return nil
-	case http.StatusUnauthorized:
-		return ErrRequireAuth
-	case http.StatusForbidden:
-		return ErrInvalidAuth
-	case http.StatusInternalServerError:
-		return ErrRemoteInternal
-	default:
-		return fmt.Errorf("Unexpected HTTP response code %d", resp.StatusCode)
-	}
-}

remote/http_test.go

@@ -1,331 +0,0 @@
-package remote
-
-import (
-	"bytes"
-	"crypto/md5"
-	"encoding/base64"
-	"io"
-	"net/http"
-	"net/http/httptest"
-	"testing"
-
-	"github.com/hashicorp/terraform/terraform"
-)
-
-func TestHTTPRemote_Interface(t *testing.T) {
-	var client interface{} = &HTTPRemoteClient{}
-	if _, ok := client.(RemoteClient); !ok {
-		t.Fatalf("does not implement interface")
-	}
-}
-
-func TestHTTPRemote_Validate(t *testing.T) {
-	conf := map[string]string{}
-	if _, err := NewHTTPRemoteClient(conf); err == nil {
-		t.Fatalf("expect error")
-	}
-
-	conf["address"] = ""
-	if _, err := NewHTTPRemoteClient(conf); err == nil {
-		t.Fatalf("expect error")
-	}
-
-	conf["address"] = "*"
-	if _, err := NewHTTPRemoteClient(conf); err == nil {
-		t.Fatalf("expect error")
-	}
-
-	conf["address"] = "http://cool.com"
-	if _, err := NewHTTPRemoteClient(conf); err != nil {
-		t.Fatalf("err: %v", err)
-	}
-}
-
-func TestHTTPRemote_GetState(t *testing.T) {
-	type tcase struct {
-		Code      int
-		Header    http.Header
-		Body      []byte
-		ExpectMD5 []byte
-		ExpectErr string
-	}
-	inp := []byte("testing")
-	inpMD5 := md5.Sum(inp)
-	hash := inpMD5[:16]
-	cases := []*tcase{
-		&tcase{
-			Code:      http.StatusOK,
-			Body:      inp,
-			ExpectMD5: hash,
-		},
-		&tcase{
-			Code: http.StatusNoContent,
-		},
-		&tcase{
-			Code: http.StatusNotFound,
-		},
-		&tcase{
-			Code:      http.StatusInternalServerError,
-			ExpectErr: "Remote server reporting internal error",
-		},
-		&tcase{
-			Code:      418,
-			ExpectErr: "Unexpected HTTP response code 418",
-		},
-	}
-
-	for _, tc := range cases {
-		cb := func(resp http.ResponseWriter, req *http.Request) {
-			for k, v := range tc.Header {
-				resp.Header()[k] = v
-			}
-			resp.WriteHeader(tc.Code)
-			if tc.Body != nil {
-				resp.Write(tc.Body)
-			}
-		}
-		s := httptest.NewServer(http.HandlerFunc(cb))
-		defer s.Close()
-
-		remote := &terraform.RemoteState{
-			Type: "http",
-			Config: map[string]string{
-				"address": s.URL,
-			},
-		}
-		r, err := NewClientByState(remote)
-		if err != nil {
-			t.Fatalf("Err: %v", err)
-		}
-
-		payload, err := r.GetState()
-		errStr := ""
-		if err != nil {
-			errStr = err.Error()
-		}
-		if errStr != tc.ExpectErr {
-			t.Fatalf("bad err: %v %v", errStr, tc.ExpectErr)
-		}
-
-		if tc.ExpectMD5 != nil {
-			if payload == nil || !bytes.Equal(payload.MD5, tc.ExpectMD5) {
-				t.Fatalf("bad: %#v", payload)
-			}
-		}
-
-		if tc.Body != nil {
-			if !bytes.Equal(payload.State, tc.Body) {
-				t.Fatalf("bad: %#v", payload)
-			}
-		}
-	}
-
-}
-
-func TestHTTPRemote_PutState(t *testing.T) {
-	type tcase struct {
-		Code      int
-		Path      string
-		Header    http.Header
-		Body      []byte
-		ExpectMD5 []byte
-		Force     bool
-		ExpectErr string
-	}
-	inp := []byte("testing")
-	inpMD5 := md5.Sum(inp)
-	hash := inpMD5[:16]
-	cases := []*tcase{
-		&tcase{
-			Code:      http.StatusOK,
-			Path:      "/foobar",
-			Body:      inp,
-			ExpectMD5: hash,
-		},
-		&tcase{
-			Code:      http.StatusOK,
-			Path:      "/foobar?force=true",
-			Body:      inp,
-			Force:     true,
-			ExpectMD5: hash,
-		},
-		&tcase{
-			Code:      http.StatusConflict,
-			Path:      "/foobar",
-			Body:      inp,
-			ExpectMD5: hash,
-			ExpectErr: ErrConflict.Error(),
-		},
-		&tcase{
-			Code:      http.StatusPreconditionFailed,
-			Path:      "/foobar",
-			Body:      inp,
-			ExpectMD5: hash,
-			ExpectErr: ErrServerNewer.Error(),
-		},
-		&tcase{
-			Code:      http.StatusUnauthorized,
-			Path:      "/foobar",
-			Body:      inp,
-			ExpectMD5: hash,
-			ExpectErr: ErrRequireAuth.Error(),
-		},
-		&tcase{
-			Code:      http.StatusForbidden,
-			Path:      "/foobar",
-			Body:      inp,
-			ExpectMD5: hash,
-			ExpectErr: ErrInvalidAuth.Error(),
-		},
-		&tcase{
-			Code:      http.StatusInternalServerError,
-			Path:      "/foobar",
-			Body:      inp,
-			ExpectMD5: hash,
-			ExpectErr: ErrRemoteInternal.Error(),
-		},
-		&tcase{
-			Code:      418,
-			Path:      "/foobar",
-			Body:      inp,
-			ExpectMD5: hash,
-			ExpectErr: "Unexpected HTTP response code 418",
-		},
-	}
-
-	for _, tc := range cases {
-		cb := func(resp http.ResponseWriter, req *http.Request) {
-			for k, v := range tc.Header {
-				resp.Header()[k] = v
-			}
-			resp.WriteHeader(tc.Code)
-
-			// Verify the body
-			buf := bytes.NewBuffer(nil)
-			io.Copy(buf, req.Body)
-			if !bytes.Equal(buf.Bytes(), tc.Body) {
-				t.Fatalf("bad body: %v", buf.Bytes())
-			}
-
-			// Verify the path
-			req.URL.Host = ""
-			if req.URL.String() != tc.Path {
-				t.Fatalf("Bad path: %v %v", req.URL.String(), tc.Path)
-			}
-
-			// Verify the content length
-			if req.ContentLength != int64(len(tc.Body)) {
-				t.Fatalf("bad content length: %d", req.ContentLength)
-			}
-
-			// Verify the Content-MD5
-			b64 := req.Header.Get("Content-MD5")
-			raw, _ := base64.StdEncoding.DecodeString(b64)
-			if !bytes.Equal(raw, tc.ExpectMD5) {
-				t.Fatalf("bad md5: %v", raw)
-			}
-		}
-		s := httptest.NewServer(http.HandlerFunc(cb))
-		defer s.Close()
-
-		remote := &terraform.RemoteState{
-			Type: "http",
-			Config: map[string]string{
-				"address": s.URL + "/foobar",
-			},
-		}
-		r, err := NewClientByState(remote)
-		if err != nil {
-			t.Fatalf("Err: %v", err)
-		}
-
-		err = r.PutState(tc.Body, tc.Force)
-		errStr := ""
-		if err != nil {
-			errStr = err.Error()
-		}
-		if errStr != tc.ExpectErr {
-			t.Fatalf("bad err: %v %v", errStr, tc.ExpectErr)
-		}
-	}
-}
-
-func TestHTTPRemote_DeleteState(t *testing.T) {
-	type tcase struct {
-		Code      int
-		Path      string
-		Header    http.Header
-		ExpectErr string
-	}
-	cases := []*tcase{
-		&tcase{
-			Code: http.StatusOK,
-			Path: "/foobar",
-		},
-		&tcase{
-			Code: http.StatusNoContent,
-			Path: "/foobar",
-		},
-		&tcase{
-			Code: http.StatusNotFound,
-			Path: "/foobar",
-		},
-		&tcase{
-			Code:      http.StatusUnauthorized,
-			Path:      "/foobar",
-			ExpectErr: ErrRequireAuth.Error(),
-		},
-		&tcase{
-			Code:      http.StatusForbidden,
-			Path:      "/foobar",
-			ExpectErr: ErrInvalidAuth.Error(),
-		},
-		&tcase{
-			Code:      http.StatusInternalServerError,
-			Path:      "/foobar",
-			ExpectErr: ErrRemoteInternal.Error(),
-		},
-		&tcase{
-			Code:      418,
-			Path:      "/foobar",
-			ExpectErr: "Unexpected HTTP response code 418",
-		},
-	}
-
-	for _, tc := range cases {
-		cb := func(resp http.ResponseWriter, req *http.Request) {
-			for k, v := range tc.Header {
-				resp.Header()[k] = v
-			}
-			resp.WriteHeader(tc.Code)
-
-			// Verify the path
-			req.URL.Host = ""
-			if req.URL.String() != tc.Path {
-				t.Fatalf("Bad path: %v %v", req.URL.String(), tc.Path)
-			}
-		}
-		s := httptest.NewServer(http.HandlerFunc(cb))
-		defer s.Close()
-
-		remote := &terraform.RemoteState{
-			Type: "http",
-			Config: map[string]string{
-				"address": s.URL + "/foobar",
-			},
-		}
-		r, err := NewClientByState(remote)
-		if err != nil {
-			t.Fatalf("Err: %v", err)
-		}
-
-		err = r.DeleteState()
-		errStr := ""
-		if err != nil {
-			errStr = err.Error()
-		}
-		if errStr != tc.ExpectErr {
-			t.Fatalf("bad err: %v %v", errStr, tc.ExpectErr)
-		}
-	}
-}

remote/remote.go

@@ -1,448 +0,0 @@
-package remote
-
-import (
-	"bytes"
-	"crypto/md5"
-	"fmt"
-	"io"
-	"io/ioutil"
-	"os"
-	"path/filepath"
-
-	"github.com/hashicorp/terraform/terraform"
-)
-
-const (
-	// LocalDirectory is the directory created in the working
-	// dir to hold the remote state file.
-	LocalDirectory = ".terraform"
-
-	// HiddenStateFile is the name of the state file in the
-	// LocalDirectory
-	HiddenStateFile = "terraform.tfstate"
-
-	// BackupHiddenStateFile is the path we backup the state
-	// file to before modifications are made
-	BackupHiddenStateFile = "terraform.tfstate.backup"
-)
-
-// StateChangeResult is used to communicate to a caller
-// what actions have been taken when updating a state file
-type StateChangeResult int
-
-const (
-	// StateChangeNoop indicates nothing has happened,
-	// but that does not indicate an error. Everything is
-	// just up to date. (Push/Pull)
-	StateChangeNoop StateChangeResult = iota
-
-	// StateChangeInit indicates that there is no local or
-	// remote state, and that the state was initialized
-	StateChangeInit
-
-	// StateChangeUpdateLocal indicates the local state
-	// was updated. (Pull)
-	StateChangeUpdateLocal
-
-	// StateChangeUpdateRemote indicates the remote state
-	// was updated. (Push)
-	StateChangeUpdateRemote
-
-	// StateChangeLocalNewer means the pull was a no-op
-	// because the local state is newer than that of the
-	// server. This means a Push should take place. (Pull)
-	StateChangeLocalNewer
-
-	// StateChangeRemoteNewer means the push was a no-op
-	// because the remote state is newer than that of the
-	// local state. This means a Pull should take place.
-	// (Push)
-	StateChangeRemoteNewer
-
-	// StateChangeConflict means that the push or pull
-	// was a no-op because there is a conflict. This means
-	// there are multiple state definitions at the same
-	// serial number with different contents. This requires
-	// an operator to intervene and resolve the conflict.
-	// Shame on the user for doing concurrent apply.
-	// (Push/Pull)
-	StateChangeConflict
-)
-
-func (sc StateChangeResult) String() string {
-	switch sc {
-	case StateChangeNoop:
-		return "Local and remote state in sync"
-	case StateChangeInit:
-		return "Local state initialized"
-	case StateChangeUpdateLocal:
-		return "Local state updated"
-	case StateChangeUpdateRemote:
-		return "Remote state updated"
-	case StateChangeLocalNewer:
-		return "Local state is newer than remote state, push required"
-	case StateChangeRemoteNewer:
-		return "Remote state is newer than local state, pull required"
-	case StateChangeConflict:
-		return "Local and remote state conflict, manual resolution required"
-	default:
-		return fmt.Sprintf("Unknown state change type: %d", sc)
-	}
-}
-
-// SuccessfulPull is used to clasify the StateChangeResult for
-// a pull operation. This is different by operation, but can be used
-// to determine a proper exit code.
-func (sc StateChangeResult) SuccessfulPull() bool {
-	switch sc {
-	case StateChangeNoop:
-		return true
-	case StateChangeInit:
-		return true
-	case StateChangeUpdateLocal:
-		return true
-	case StateChangeLocalNewer:
-		return false
-	case StateChangeConflict:
-		return false
-	default:
-		return false
-	}
-}
-
-// SuccessfulPush is used to clasify the StateChangeResult for
-// a push operation. This is different by operation, but can be used
-// to determine a proper exit code
-func (sc StateChangeResult) SuccessfulPush() bool {
-	switch sc {
-	case StateChangeNoop:
-		return true
-	case StateChangeUpdateRemote:
-		return true
-	case StateChangeRemoteNewer:
-		return false
-	case StateChangeConflict:
-		return false
-	default:
-		return false
-	}
-}
-
-// EnsureDirectory is used to make sure the local storage
-// directory exists
-func EnsureDirectory() error {
-	cwd, err := os.Getwd()
-	if err != nil {
-		return fmt.Errorf("Failed to get current directory: %v", err)
-	}
-	path := filepath.Join(cwd, LocalDirectory)
-	if err := os.Mkdir(path, 0770); err != nil {
-		if os.IsExist(err) {
-			return nil
-		}
-		return fmt.Errorf("Failed to make directory '%s': %v", path, err)
-	}
-	return nil
-}
-
-// HiddenStatePath is used to return the path to the hidden state file,
-// should there be one.
-// TODO: Rename to LocalStatePath
-func HiddenStatePath() (string, error) {
-	cwd, err := os.Getwd()
-	if err != nil {
-		return "", fmt.Errorf("Failed to get current directory: %v", err)
-	}
-	path := filepath.Join(cwd, LocalDirectory, HiddenStateFile)
-	return path, nil
-}
-
-// HaveLocalState is used to check if we have a local state file
-func HaveLocalState() (bool, error) {
-	path, err := HiddenStatePath()
-	if err != nil {
-		return false, err
-	}
-	return ExistsFile(path)
-}
-
-// ExistsFile is used to check if a given file exists
-func ExistsFile(path string) (bool, error) {
-	_, err := os.Stat(path)
-	if err == nil {
-		return true, nil
-	}
-	if os.IsNotExist(err) {
-		return false, nil
-	}
-	return false, err
-}
-
-// ValidConfig does a purely logical validation of the remote config
-func ValidConfig(conf *terraform.RemoteState) error {
-	// Default the type to Atlas
-	if conf.Type == "" {
-		conf.Type = "atlas"
-	}
-	_, err := NewClientByState(conf)
-	if err != nil {
-		return err
-	}
-	return nil
-}
-
-// ReadLocalState is used to read and parse the local state file
-func ReadLocalState() (*terraform.State, []byte, error) {
-	path, err := HiddenStatePath()
-	if err != nil {
-		return nil, nil, err
-	}
-
-	// Open the existing file
-	raw, err := ioutil.ReadFile(path)
-	if err != nil {
-		if os.IsNotExist(err) {
-			return nil, nil, nil
-		}
-		return nil, nil, fmt.Errorf("Failed to open state file '%s': %s", path, err)
-	}
-
-	// Decode the state
-	state, err := terraform.ReadState(bytes.NewReader(raw))
-	if err != nil {
-		return nil, nil, fmt.Errorf("Failed to read state file '%s': %v", path, err)
-	}
-	return state, raw, nil
-}
-
-// RefreshState is used to read the remote state given
-// the configuration for the remote endpoint, and update
-// the local state if necessary.
-func RefreshState(conf *terraform.RemoteState) (StateChangeResult, error) {
-	if conf == nil {
-		return StateChangeNoop, fmt.Errorf("Missing remote server configuration")
-	}
-
-	// Read the state from the server
-	client, err := NewClientByState(conf)
-	if err != nil {
-		return StateChangeNoop,
-			fmt.Errorf("Failed to create remote client: %v", err)
-	}
-	payload, err := client.GetState()
-	if err != nil {
-		return StateChangeNoop,
-			fmt.Errorf("Failed to read remote state: %v", err)
-	}
-
-	// Parse the remote state
-	var remoteState *terraform.State
-	if payload != nil {
-		remoteState, err = terraform.ReadState(bytes.NewReader(payload.State))
-		if err != nil {
-			return StateChangeNoop,
-				fmt.Errorf("Failed to parse remote state: %v", err)
-		}
-
-		// Ensure we understand the remote version!
-		if remoteState.Version > terraform.StateVersion {
-			return StateChangeNoop, fmt.Errorf(
-				`Remote state is version %d, this version of Terraform only understands up to %d`, remoteState.Version, terraform.StateVersion)
-		}
-	}
-
-	// Decode the state
-	localState, raw, err := ReadLocalState()
-	if err != nil {
-		return StateChangeNoop, err
-	}
-
-	// We need to handle the matrix of cases in reconciling
-	// the local and remote state. Primarily the concern is
-	// around the Serial number which should grow monotonically.
-	// Additionally, we use the MD5 to detect a conflict for
-	// a given Serial.
-	switch {
-	case remoteState == nil && localState == nil:
-		// Initialize a blank state
-		out, _ := blankState(conf)
-		if err := Persist(bytes.NewReader(out)); err != nil {
-			return StateChangeNoop,
-				fmt.Errorf("Failed to persist state: %v", err)
-		}
-		return StateChangeInit, nil
-
-	case remoteState == nil && localState != nil:
-		// User should probably do a push, nothing to do
-		return StateChangeLocalNewer, nil
-
-	case remoteState != nil && localState == nil:
-		goto PERSIST
-
-	case remoteState.Serial < localState.Serial:
-		// User should probably do a push, nothing to do
-		return StateChangeLocalNewer, nil
-
-	case remoteState.Serial > localState.Serial:
-		goto PERSIST
-
-	case remoteState.Serial == localState.Serial:
-		// Check for a hash collision on the local/remote state
-		localMD5 := md5.Sum(raw)
-		if bytes.Equal(localMD5[:md5.Size], payload.MD5) {
-			// Hash collision, everything is up-to-date
-			return StateChangeNoop, nil
-		} else {
-			// This is very bad. This means we have 2 state files
-			// with the same Serial but a different hash. Most probably
-			// explaination is two parallel apply operations. This
-			// requires a manual reconciliation.
-			return StateChangeConflict, nil
-		}
-	default:
-		// We should not reach this point
-		panic("Unhandled remote update case")
-	}
-
-PERSIST:
-	// Update the local state from the remote state
-	if err := Persist(bytes.NewReader(payload.State)); err != nil {
-		return StateChangeNoop,
-			fmt.Errorf("Failed to persist state: %v", err)
-	}
-	return StateChangeUpdateLocal, nil
-}
-
-// PushState is used to read the local state and
-// update the remote state if necessary. The state push
-// can be 'forced' to override any conflict detection
-// on the server-side.
-func PushState(conf *terraform.RemoteState, force bool) (StateChangeResult, error) {
-	// Read the local state
-	_, raw, err := ReadLocalState()
-	if err != nil {
-		return StateChangeNoop, err
-	}
-
-	// Check if there is no local state
-	if raw == nil {
-		return StateChangeNoop, fmt.Errorf("No local state to push")
-	}
-
-	// Push the state to the server
-	client, err := NewClientByState(conf)
-	if err != nil {
-		return StateChangeNoop,
-			fmt.Errorf("Failed to create remote client: %v", err)
-	}
-	err = client.PutState(raw, force)
-
-	// Handle the various edge cases
-	switch err {
-	case nil:
-		return StateChangeUpdateRemote, nil
-	case ErrServerNewer:
-		return StateChangeRemoteNewer, nil
-	case ErrConflict:
-		return StateChangeConflict, nil
-	default:
-		return StateChangeNoop, err
-	}
-}
-
-// DeleteState is used to delete the remote state given
-// the configuration for the remote endpoint.
-func DeleteState(conf *terraform.RemoteState) error {
-	if conf == nil {
-		return fmt.Errorf("Missing remote server configuration")
-	}
-
-	// Setup the client
-	client, err := NewClientByState(conf)
-	if err != nil {
-		return fmt.Errorf("Failed to create remote client: %v", err)
-	}
-
-	// Destroy the state
-	err = client.DeleteState()
-	if err != nil {
-		return fmt.Errorf("Failed to delete remote state: %v", err)
-	}
-	return nil
-}
-
-// blankState is used to return a serialized form of a blank state
-// with only the remote info.
-func blankState(conf *terraform.RemoteState) ([]byte, error) {
-	blank := terraform.NewState()
-	blank.Remote = conf
-	buf := bytes.NewBuffer(nil)
-	err := terraform.WriteState(blank, buf)
-	return buf.Bytes(), err
-}
-
-// PersistState is used to persist out the given terraform state
-// in our local state cache location.
-func PersistState(s *terraform.State) error {
-	buf := bytes.NewBuffer(nil)
-	if err := terraform.WriteState(s, buf); err != nil {
-		return fmt.Errorf("Failed to encode state: %v", err)
-	}
-	if err := Persist(buf); err != nil {
-		return err
-	}
-	return nil
-}
-
-// Persist is used to write out the state given by a reader (likely
-// being streamed from a remote server) to the local storage.
-func Persist(r io.Reader) error {
-	cwd, err := os.Getwd()
-	if err != nil {
-		return fmt.Errorf("Failed to get current directory: %v", err)
-	}
-	statePath := filepath.Join(cwd, LocalDirectory, HiddenStateFile)
-	backupPath := filepath.Join(cwd, LocalDirectory, BackupHiddenStateFile)
-
-	// Backup the old file if it exists
-	if err := CopyFile(statePath, backupPath); err != nil {
-		return fmt.Errorf("Failed to backup state file '%s' to '%s': %v", statePath, backupPath, err)
-	}
-
-	// Open the state path
-	fh, err := os.Create(statePath)
-	if err != nil {
-		return fmt.Errorf("Failed to open state file '%s': %v", statePath, err)
-	}
-
-	// Copy the new state
-	_, err = io.Copy(fh, r)
-	fh.Close()
-	if err != nil {
-		os.Remove(statePath)
-		return fmt.Errorf("Failed to persist state file: %v", err)
-	}
-	return nil
-}
-
-// CopyFile is used to copy from a source file if it exists to a destination.
-// This is used to create a backup of the state file.
-func CopyFile(src, dst string) error {
-	srcFH, err := os.Open(src)
-	if err != nil {
-		if os.IsNotExist(err) {
-			return nil
-		}
-		return err
-	}
-	defer srcFH.Close()
-
-	dstFH, err := os.Create(dst)
-	if err != nil {
-		return err
-	}
-	defer dstFH.Close()
-
-	_, err = io.Copy(dstFH, srcFH)
-	return err
-}

remote/remote_test.go

@@ -1,480 +0,0 @@
-package remote
-
-import (
-	"bytes"
-	"crypto/md5"
-	"encoding/base64"
-	"encoding/json"
-	"io/ioutil"
-	"net/http"
-	"net/http/httptest"
-	"os"
-	"path/filepath"
-	"testing"
-
-	"github.com/hashicorp/terraform/terraform"
-)
-
-func TestEnsureDirectory(t *testing.T) {
-	err := EnsureDirectory()
-	if err != nil {
-		t.Fatalf("Err: %v", err)
-	}
-
-	cwd, _ := os.Getwd()
-	path := filepath.Join(cwd, LocalDirectory)
-
-	_, err = os.Stat(path)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-}
-
-func TestHiddenStatePath(t *testing.T) {
-	path, err := HiddenStatePath()
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	cwd, _ := os.Getwd()
-	expect := filepath.Join(cwd, LocalDirectory, HiddenStateFile)
-
-	if path != expect {
-		t.Fatalf("bad: %v", path)
-	}
-}
-
-func TestValidConfig(t *testing.T) {
-	conf := &terraform.RemoteState{
-		Type:   "",
-		Config: map[string]string{},
-	}
-	if err := ValidConfig(conf); err == nil {
-		t.Fatalf("blank should be not be valid: %v", err)
-	}
-	conf.Config["name"] = "hashicorp/test-remote-state"
-	conf.Config["access_token"] = "abcd"
-	if err := ValidConfig(conf); err != nil {
-		t.Fatalf("should be valid")
-	}
-	if conf.Type != "atlas" {
-		t.Fatalf("should default to atlas")
-	}
-}
-
-func TestRefreshState_Init(t *testing.T) {
-	defer testFixCwd(testDir(t))
-	remote, srv := testRemote(t, nil)
-	defer srv.Close()
-
-	sc, err := RefreshState(remote)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	if sc != StateChangeInit {
-		t.Fatalf("bad: %s", sc)
-	}
-
-	local := testReadLocal(t)
-	if !local.Remote.Equals(remote) {
-		t.Fatalf("Bad: %#v", local)
-	}
-	if local.Serial != 1 {
-		t.Fatalf("Bad: %#v", local)
-	}
-}
-
-func TestRefreshState_NewVersion(t *testing.T) {
-	defer testFixCwd(testDir(t))
-
-	rs := terraform.NewState()
-	rs.Serial = 100
-	rs.Version = terraform.StateVersion + 1
-	remote, srv := testRemote(t, rs)
-	defer srv.Close()
-
-	local := terraform.NewState()
-	local.Serial = 99
-	testWriteLocal(t, local)
-
-	_, err := RefreshState(remote)
-	if err == nil {
-		t.Fatalf("New version should fail!")
-	}
-}
-
-func TestRefreshState_Noop(t *testing.T) {
-	defer testFixCwd(testDir(t))
-
-	rs := terraform.NewState()
-	rs.Serial = 100
-	remote, srv := testRemote(t, rs)
-	defer srv.Close()
-
-	local := terraform.NewState()
-	local.Serial = 100
-	testWriteLocal(t, local)
-
-	sc, err := RefreshState(remote)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	if sc != StateChangeNoop {
-		t.Fatalf("bad: %s", sc)
-	}
-}
-
-func TestRefreshState_UpdateLocal(t *testing.T) {
-	defer testFixCwd(testDir(t))
-
-	rs := terraform.NewState()
-	rs.Serial = 100
-	remote, srv := testRemote(t, rs)
-	defer srv.Close()
-
-	local := terraform.NewState()
-	local.Serial = 99
-	testWriteLocal(t, local)
-
-	sc, err := RefreshState(remote)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	if sc != StateChangeUpdateLocal {
-		t.Fatalf("bad: %s", sc)
-	}
-
-	// Should update
-	local2 := testReadLocal(t)
-	if local2.Serial != 100 {
-		t.Fatalf("Bad: %#v", local2)
-	}
-}
-
-func TestRefreshState_LocalNewer(t *testing.T) {
-	defer testFixCwd(testDir(t))
-
-	rs := terraform.NewState()
-	rs.Serial = 99
-	remote, srv := testRemote(t, rs)
-	defer srv.Close()
-
-	local := terraform.NewState()
-	local.Serial = 100
-	testWriteLocal(t, local)
-
-	sc, err := RefreshState(remote)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	if sc != StateChangeLocalNewer {
-		t.Fatalf("bad: %s", sc)
-	}
-}
-
-func TestRefreshState_Conflict(t *testing.T) {
-	defer testFixCwd(testDir(t))
-
-	rs := terraform.NewState()
-	rs.Serial = 50
-	rs.RootModule().Outputs["foo"] = "bar"
-	remote, srv := testRemote(t, rs)
-	defer srv.Close()
-
-	local := terraform.NewState()
-	local.Serial = 50
-	local.RootModule().Outputs["foo"] = "baz"
-	testWriteLocal(t, local)
-
-	sc, err := RefreshState(remote)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	if sc != StateChangeConflict {
-		t.Fatalf("bad: %s", sc)
-	}
-}
-
-func TestPushState_NoState(t *testing.T) {
-	defer testFixCwd(testDir(t))
-
-	remote, srv := testRemotePush(t, 200)
-	defer srv.Close()
-
-	sc, err := PushState(remote, false)
-	if err.Error() != "No local state to push" {
-		t.Fatalf("err: %v", err)
-	}
-	if sc != StateChangeNoop {
-		t.Fatalf("Bad: %v", sc)
-	}
-}
-
-func TestPushState_Update(t *testing.T) {
-	defer testFixCwd(testDir(t))
-
-	remote, srv := testRemotePush(t, 200)
-	defer srv.Close()
-
-	local := terraform.NewState()
-	testWriteLocal(t, local)
-
-	sc, err := PushState(remote, false)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	if sc != StateChangeUpdateRemote {
-		t.Fatalf("Bad: %v", sc)
-	}
-}
-
-func TestPushState_RemoteNewer(t *testing.T) {
-	defer testFixCwd(testDir(t))
-
-	remote, srv := testRemotePush(t, 412)
-	defer srv.Close()
-
-	local := terraform.NewState()
-	testWriteLocal(t, local)
-
-	sc, err := PushState(remote, false)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	if sc != StateChangeRemoteNewer {
-		t.Fatalf("Bad: %v", sc)
-	}
-}
-
-func TestPushState_Conflict(t *testing.T) {
-	defer testFixCwd(testDir(t))
-
-	remote, srv := testRemotePush(t, 409)
-	defer srv.Close()
-
-	local := terraform.NewState()
-	testWriteLocal(t, local)
-
-	sc, err := PushState(remote, false)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	if sc != StateChangeConflict {
-		t.Fatalf("Bad: %v", sc)
-	}
-}
-
-func TestPushState_Error(t *testing.T) {
-	defer testFixCwd(testDir(t))
-
-	remote, srv := testRemotePush(t, 500)
-	defer srv.Close()
-
-	local := terraform.NewState()
-	testWriteLocal(t, local)
-
-	sc, err := PushState(remote, false)
-	if err != ErrRemoteInternal {
-		t.Fatalf("err: %v", err)
-	}
-	if sc != StateChangeNoop {
-		t.Fatalf("Bad: %v", sc)
-	}
-}
-
-func TestDeleteState(t *testing.T) {
-	defer testFixCwd(testDir(t))
-
-	remote, srv := testRemotePush(t, 200)
-	defer srv.Close()
-
-	local := terraform.NewState()
-	testWriteLocal(t, local)
-
-	err := DeleteState(remote)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-}
-
-func TestBlankState(t *testing.T) {
-	remote := &terraform.RemoteState{
-		Type: "http",
-		Config: map[string]string{
-			"address": "http://foo.com/",
-		},
-	}
-	r, err := blankState(remote)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	s, err := terraform.ReadState(bytes.NewReader(r))
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	if !remote.Equals(s.Remote) {
-		t.Fatalf("remote mismatch")
-	}
-}
-
-func TestPersist(t *testing.T) {
-	tmp, cwd := testDir(t)
-	defer testFixCwd(tmp, cwd)
-
-	EnsureDirectory()
-
-	// Place old state file, should backup
-	old := filepath.Join(tmp, LocalDirectory, HiddenStateFile)
-	ioutil.WriteFile(old, []byte("test"), 0777)
-
-	remote := &terraform.RemoteState{
-		Type: "http",
-		Config: map[string]string{
-			"address": "http://foo.com/",
-		},
-	}
-	blank, _ := blankState(remote)
-	if err := Persist(bytes.NewReader(blank)); err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	// Check for backup
-	backup := filepath.Join(tmp, LocalDirectory, BackupHiddenStateFile)
-	out, err := ioutil.ReadFile(backup)
-	if err != nil {
-		t.Fatalf("Err: %v", err)
-	}
-	if string(out) != "test" {
-		t.Fatalf("bad: %v", out)
-	}
-
-	// Read the state
-	out, err = ioutil.ReadFile(old)
-	if err != nil {
-		t.Fatalf("Err: %v", err)
-	}
-	s, err := terraform.ReadState(bytes.NewReader(out))
-	if err != nil {
-		t.Fatalf("Err: %v", err)
-	}
-
-	// Check the remote
-	if !remote.Equals(s.Remote) {
-		t.Fatalf("remote mismatch")
-	}
-}
-
-// testRemote is used to make a test HTTP server to
-// return a given state file
-func testRemote(t *testing.T, s *terraform.State) (*terraform.RemoteState, *httptest.Server) {
-	var b64md5 string
-	buf := bytes.NewBuffer(nil)
-
-	if s != nil {
-		enc := json.NewEncoder(buf)
-		if err := enc.Encode(s); err != nil {
-			t.Fatalf("err: %v", err)
-		}
-		md5 := md5.Sum(buf.Bytes())
-		b64md5 = base64.StdEncoding.EncodeToString(md5[:16])
-	}
-
-	cb := func(resp http.ResponseWriter, req *http.Request) {
-		if s == nil {
-			resp.WriteHeader(404)
-			return
-		}
-		resp.Header().Set("Content-MD5", b64md5)
-		resp.Write(buf.Bytes())
-	}
-	srv := httptest.NewServer(http.HandlerFunc(cb))
-	remote := &terraform.RemoteState{
-		Type: "http",
-		Config: map[string]string{
-			"address": srv.URL,
-		},
-	}
-	return remote, srv
-}
-
-// testRemotePush is used to make a test HTTP server to
-// return a given status code on push
-func testRemotePush(t *testing.T, c int) (*terraform.RemoteState, *httptest.Server) {
-	cb := func(resp http.ResponseWriter, req *http.Request) {
-		resp.WriteHeader(c)
-	}
-	srv := httptest.NewServer(http.HandlerFunc(cb))
-	remote := &terraform.RemoteState{
-		Type: "http",
-		Config: map[string]string{
-			"address": srv.URL,
-		},
-	}
-	return remote, srv
-}
-
-// testDir is used to change the current working directory
-// into a test directory that should be remoted after
-func testDir(t *testing.T) (string, string) {
-	tmp, err := ioutil.TempDir("", "remote")
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	cwd, err := os.Getwd()
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	os.Chdir(tmp)
-	if err := EnsureDirectory(); err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	return tmp, cwd
-}
-
-// testFixCwd is used to as a defer to testDir
-func testFixCwd(tmp, cwd string) {
-	os.Chdir(cwd)
-	os.RemoveAll(tmp)
-}
-
-// testReadLocal is used to just get the local state
-func testReadLocal(t *testing.T) *terraform.State {
-	path, err := HiddenStatePath()
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	raw, err := ioutil.ReadFile(path)
-	if err != nil && !os.IsNotExist(err) {
-		t.Fatalf("err: %v", err)
-	}
-	if raw == nil {
-		return nil
-	}
-	s, err := terraform.ReadState(bytes.NewReader(raw))
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	return s
-}
-
-// testWriteLocal is used to write the local state
-func testWriteLocal(t *testing.T, s *terraform.State) {
-	path, err := HiddenStatePath()
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	buf := bytes.NewBuffer(nil)
-	enc := json.NewEncoder(buf)
-	if err := enc.Encode(s); err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	err = ioutil.WriteFile(path, buf.Bytes(), 0777)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-}

state/backup.go

@@ -0,0 +1,63 @@
+package state
+
+import (
+	"github.com/hashicorp/terraform/terraform"
+)
+
+// BackupState wraps a State that backs up the state on the first time that
+// a WriteState or PersistState is called.
+//
+// If Path exists, it will be overwritten.
+type BackupState struct {
+	Real State
+	Path string
+
+	done bool
+}
+
+func (s *BackupState) State() *terraform.State {
+	return s.Real.State()
+}
+
+func (s *BackupState) RefreshState() error {
+	return s.Real.RefreshState()
+}
+
+func (s *BackupState) WriteState(state *terraform.State) error {
+	if !s.done {
+		if err := s.backup(); err != nil {
+			return err
+		}
+	}
+
+	return s.Real.WriteState(state)
+}
+
+func (s *BackupState) PersistState() error {
+	if !s.done {
+		if err := s.backup(); err != nil {
+			return err
+		}
+	}
+
+	return s.Real.PersistState()
+}
+
+func (s *BackupState) backup() error {
+	state := s.Real.State()
+	if state == nil {
+		if err := s.Real.RefreshState(); err != nil {
+			return err
+		}
+
+		state = s.Real.State()
+	}
+
+	ls := &LocalState{Path: s.Path}
+	if err := ls.WriteState(state); err != nil {
+		return err
+	}
+
+	s.done = true
+	return nil
+}

state/backup_test.go

@@ -0,0 +1,29 @@
+package state
+
+import (
+	"io/ioutil"
+	"os"
+	"testing"
+)
+
+func TestBackupState(t *testing.T) {
+	f, err := ioutil.TempFile("", "tf")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	f.Close()
+	defer os.Remove(f.Name())
+
+	ls := testLocalState(t)
+	defer os.Remove(ls.Path)
+	TestState(t, &BackupState{
+		Real: ls,
+		Path: f.Name(),
+	})
+
+	if fi, err := os.Stat(f.Name()); err != nil {
+		t.Fatalf("err: %s", err)
+	} else if fi.Size() == 0 {
+		t.Fatalf("bad: %d", fi.Size())
+	}
+}

state/cache.go

@@ -0,0 +1,233 @@
+package state
+
+import (
+	"fmt"
+	"reflect"
+
+	"github.com/hashicorp/terraform/terraform"
+)
+
+// CacheState is an implementation of the state interfaces that uses
+// a StateReadWriter for a local cache.
+type CacheState struct {
+	Cache   CacheStateCache
+	Durable CacheStateDurable
+
+	refreshResult CacheRefreshResult
+	state         *terraform.State
+}
+
+// StateReader impl.
+func (s *CacheState) State() *terraform.State {
+	return s.state
+}
+
+// WriteState will write and persist the state to the cache.
+//
+// StateWriter impl.
+func (s *CacheState) WriteState(state *terraform.State) error {
+	if err := s.Cache.WriteState(state); err != nil {
+		return err
+	}
+
+	s.state = state
+	return s.Cache.PersistState()
+}
+
+// RefreshState will refresh both the cache and the durable states. It
+// can return a myriad of errors (defined at the top of this file) depending
+// on potential conflicts that can occur while doing this.
+//
+// If the durable state is newer than the local cache, then the local cache
+// will be replaced with the durable.
+//
+// StateRefresher impl.
+func (s *CacheState) RefreshState() error {
+	// Refresh the durable state
+	if err := s.Durable.RefreshState(); err != nil {
+		return err
+	}
+
+	// Refresh the cached state
+	if err := s.Cache.RefreshState(); err != nil {
+		return err
+	}
+
+	// Handle the matrix of cases that can happen when comparing these
+	// two states.
+	cached := s.Cache.State()
+	durable := s.Durable.State()
+	switch {
+	case cached == nil && durable == nil:
+		// Initialized
+		s.refreshResult = CacheRefreshInit
+	case cached != nil && durable == nil:
+		// Cache is newer than remote. Not a big deal, user can just
+		// persist to get correct state.
+		s.refreshResult = CacheRefreshLocalNewer
+	case cached == nil && durable != nil:
+		// Cache should be updated since the remote is set but cache isn't
+		s.refreshResult = CacheRefreshUpdateLocal
+	case durable.Serial < cached.Serial:
+		// Cache is newer than remote. Not a big deal, user can just
+		// persist to get correct state.
+		s.refreshResult = CacheRefreshLocalNewer
+	case durable.Serial > cached.Serial:
+		// Cache should be updated since the remote is newer
+		s.refreshResult = CacheRefreshUpdateLocal
+	case durable.Serial == cached.Serial:
+		// They're supposedly equal, verify.
+		if reflect.DeepEqual(cached, durable) {
+			// Hashes are the same, everything is great
+			s.refreshResult = CacheRefreshNoop
+			break
+		}
+
+		// This is very bad. This means we have two state files that
+		// have the same serial but have a different hash. We can't
+		// reconcile this. The most likely cause is parallel apply
+		// operations.
+		s.refreshResult = CacheRefreshConflict
+
+		// Return early so we don't updtae the state
+		return nil
+	default:
+		panic("unhandled cache refresh state")
+	}
+
+	if s.refreshResult == CacheRefreshUpdateLocal {
+		if err := s.Cache.WriteState(durable); err != nil {
+			s.refreshResult = CacheRefreshNoop
+			return err
+		}
+		if err := s.Cache.PersistState(); err != nil {
+			s.refreshResult = CacheRefreshNoop
+			return err
+		}
+	}
+
+	s.state = cached
+
+	return nil
+}
+
+// RefreshResult returns the result of the last refresh.
+func (s *CacheState) RefreshResult() CacheRefreshResult {
+	return s.refreshResult
+}
+
+// PersistState takes the local cache, assuming it is newer than the remote
+// state, and persists it to the durable storage. If you want to challenge the
+// assumption that the local state is the latest, call a RefreshState prior
+// to this.
+//
+// StatePersister impl.
+func (s *CacheState) PersistState() error {
+	if err := s.Durable.WriteState(s.state); err != nil {
+		return err
+	}
+
+	return s.Durable.PersistState()
+}
+
+// CacheStateCache is the meta-interface that must be implemented for
+// the cache for the CacheState.
+type CacheStateCache interface {
+	StateReader
+	StateWriter
+	StatePersister
+	StateRefresher
+}
+
+// CacheStateDurable is the meta-interface that must be implemented for
+// the durable storage for CacheState.
+type CacheStateDurable interface {
+	StateReader
+	StateWriter
+	StatePersister
+	StateRefresher
+}
+
+// CacheRefreshResult is used to explain the result of the previous
+// RefreshState for a CacheState.
+type CacheRefreshResult int
+
+const (
+	// CacheRefreshNoop indicates nothing has happened,
+	// but that does not indicate an error. Everything is
+	// just up to date. (Push/Pull)
+	CacheRefreshNoop CacheRefreshResult = iota
+
+	// CacheRefreshInit indicates that there is no local or
+	// remote state, and that the state was initialized
+	CacheRefreshInit
+
+	// CacheRefreshUpdateLocal indicates the local state
+	// was updated. (Pull)
+	CacheRefreshUpdateLocal
+
+	// CacheRefreshUpdateRemote indicates the remote state
+	// was updated. (Push)
+	CacheRefreshUpdateRemote
+
+	// CacheRefreshLocalNewer means the pull was a no-op
+	// because the local state is newer than that of the
+	// server. This means a Push should take place. (Pull)
+	CacheRefreshLocalNewer
+
+	// CacheRefreshRemoteNewer means the push was a no-op
+	// because the remote state is newer than that of the
+	// local state. This means a Pull should take place.
+	// (Push)
+	CacheRefreshRemoteNewer
+
+	// CacheRefreshConflict means that the push or pull
+	// was a no-op because there is a conflict. This means
+	// there are multiple state definitions at the same
+	// serial number with different contents. This requires
+	// an operator to intervene and resolve the conflict.
+	// Shame on the user for doing concurrent apply.
+	// (Push/Pull)
+	CacheRefreshConflict
+)
+
+func (sc CacheRefreshResult) String() string {
+	switch sc {
+	case CacheRefreshNoop:
+		return "Local and remote state in sync"
+	case CacheRefreshInit:
+		return "Local state initialized"
+	case CacheRefreshUpdateLocal:
+		return "Local state updated"
+	case CacheRefreshUpdateRemote:
+		return "Remote state updated"
+	case CacheRefreshLocalNewer:
+		return "Local state is newer than remote state, push required"
+	case CacheRefreshRemoteNewer:
+		return "Remote state is newer than local state, pull required"
+	case CacheRefreshConflict:
+		return "Local and remote state conflict, manual resolution required"
+	default:
+		return fmt.Sprintf("Unknown state change type: %d", sc)
+	}
+}
+
+// SuccessfulPull is used to clasify the CacheRefreshResult for
+// a refresh operation. This is different by operation, but can be used
+// to determine a proper exit code.
+func (sc CacheRefreshResult) SuccessfulPull() bool {
+	switch sc {
+	case CacheRefreshNoop:
+		return true
+	case CacheRefreshInit:
+		return true
+	case CacheRefreshUpdateLocal:
+		return true
+	case CacheRefreshLocalNewer:
+		return false
+	case CacheRefreshConflict:
+		return false
+	default:
+		return false
+	}
+}

state/cache_test.go

@@ -0,0 +1,58 @@
+package state
+
+import (
+	"os"
+	"reflect"
+	"testing"
+)
+
+func TestCacheState(t *testing.T) {
+	cache := testLocalState(t)
+	durable := testLocalState(t)
+	defer os.Remove(cache.Path)
+	defer os.Remove(durable.Path)
+
+	TestState(t, &CacheState{
+		Cache:   cache,
+		Durable: durable,
+	})
+}
+
+func TestCacheState_persistDurable(t *testing.T) {
+	cache := testLocalState(t)
+	durable := testLocalState(t)
+	defer os.Remove(cache.Path)
+	defer os.Remove(durable.Path)
+
+	cs := &CacheState{
+		Cache:   cache,
+		Durable: durable,
+	}
+
+	state := cache.State()
+	state.Modules = nil
+	if err := cs.WriteState(state); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	if reflect.DeepEqual(cache.State(), durable.State()) {
+		t.Fatal("cache and durable should not be the same")
+	}
+
+	if err := cs.PersistState(); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	if !reflect.DeepEqual(cache.State(), durable.State()) {
+		t.Fatalf(
+			"cache and durable should be the same\n\n%#v\n\n%#v",
+			cache.State(), durable.State())
+	}
+}
+
+func TestCacheState_impl(t *testing.T) {
+	var _ StateReader = new(CacheState)
+	var _ StateWriter = new(CacheState)
+	var _ StatePersister = new(CacheState)
+	var _ StateRefresher = new(CacheState)
+}

state/inmem.go

@@ -0,0 +1,27 @@
+package state
+
+import (
+	"github.com/hashicorp/terraform/terraform"
+)
+
+// InmemState is an in-memory state storage.
+type InmemState struct {
+	state *terraform.State
+}
+
+func (s *InmemState) State() *terraform.State {
+	return s.state
+}
+
+func (s *InmemState) RefreshState() error {
+	return nil
+}
+
+func (s *InmemState) WriteState(state *terraform.State) error {
+	s.state = state
+	return nil
+}
+
+func (s *InmemState) PersistState() error {
+	return nil
+}

state/inmem_test.go

@@ -0,0 +1,16 @@
+package state
+
+import (
+	"testing"
+)
+
+func TestInmemState(t *testing.T) {
+	TestState(t, &InmemState{state: TestStateInitial()})
+}
+
+func TestInmemState_impl(t *testing.T) {
+	var _ StateReader = new(InmemState)
+	var _ StateWriter = new(InmemState)
+	var _ StatePersister = new(InmemState)
+	var _ StateRefresher = new(InmemState)
+}

state/local.go

@@ -0,0 +1,109 @@
+package state
+
+import (
+	"os"
+	"path/filepath"
+
+	"github.com/hashicorp/terraform/terraform"
+)
+
+// LocalState manages a state storage that is local to the filesystem.
+type LocalState struct {
+	// Path is the path to read the state from. PathOut is the path to
+	// write the state to. If PathOut is not specified, Path will be used.
+	// If PathOut already exists, it will be overwritten.
+	Path    string
+	PathOut string
+
+	state   *terraform.State
+	written bool
+}
+
+// SetState will force a specific state in-memory for this local state.
+func (s *LocalState) SetState(state *terraform.State) {
+	s.state = state
+}
+
+// StateReader impl.
+func (s *LocalState) State() *terraform.State {
+	return s.state
+}
+
+// WriteState for LocalState always persists the state as well.
+//
+// StateWriter impl.
+func (s *LocalState) WriteState(state *terraform.State) error {
+	s.state = state
+
+	path := s.PathOut
+	if path == "" {
+		path = s.Path
+	}
+
+	// If we don't have any state, we actually delete the file if it exists
+	if state == nil {
+		err := os.Remove(path)
+		if err != nil && os.IsNotExist(err) {
+			return nil
+		}
+
+		return err
+	}
+
+	// Create all the directories
+	if err := os.MkdirAll(filepath.Dir(path), 0755); err != nil {
+		return err
+	}
+
+	f, err := os.Create(path)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	if err := terraform.WriteState(s.state, f); err != nil {
+		return err
+	}
+
+	s.written = true
+	return nil
+}
+
+// PersistState for LocalState is a no-op since WriteState always persists.
+//
+// StatePersister impl.
+func (s *LocalState) PersistState() error {
+	return nil
+}
+
+// StateRefresher impl.
+func (s *LocalState) RefreshState() error {
+	// If we've never loaded before, read from Path, otherwise we
+	// read from PathOut.
+	path := s.Path
+	if s.written && s.PathOut != "" {
+		path = s.PathOut
+	}
+
+	f, err := os.Open(path)
+	if err != nil {
+		// It is okay if the file doesn't exist, we treat that as a nil state
+		if !os.IsNotExist(err) {
+			return err
+		}
+
+		f = nil
+	}
+
+	var state *terraform.State
+	if f != nil {
+		defer f.Close()
+		state, err = terraform.ReadState(f)
+		if err != nil {
+			return err
+		}
+	}
+
+	s.state = state
+	return nil
+}

state/local_test.go

@@ -0,0 +1,68 @@
+package state
+
+import (
+	"io/ioutil"
+	"os"
+	"testing"
+
+	"github.com/hashicorp/terraform/terraform"
+)
+
+func TestLocalState(t *testing.T) {
+	ls := testLocalState(t)
+	defer os.Remove(ls.Path)
+	TestState(t, ls)
+}
+
+func TestLocalState_pathOut(t *testing.T) {
+	f, err := ioutil.TempFile("", "tf")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	f.Close()
+	defer os.Remove(f.Name())
+
+	ls := testLocalState(t)
+	ls.PathOut = f.Name()
+	defer os.Remove(ls.Path)
+
+	TestState(t, ls)
+}
+
+func TestLocalState_nonExist(t *testing.T) {
+	ls := &LocalState{Path: "ishouldntexist"}
+	if err := ls.RefreshState(); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	if state := ls.State(); state != nil {
+		t.Fatalf("bad: %#v", state)
+	}
+}
+
+func TestLocalState_impl(t *testing.T) {
+	var _ StateReader = new(LocalState)
+	var _ StateWriter = new(LocalState)
+	var _ StatePersister = new(LocalState)
+	var _ StateRefresher = new(LocalState)
+}
+
+func testLocalState(t *testing.T) *LocalState {
+	f, err := ioutil.TempFile("", "tf")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	err = terraform.WriteState(TestStateInitial(), f)
+	f.Close()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	ls := &LocalState{Path: f.Name()}
+	if err := ls.RefreshState(); err != nil {
+		t.Fatalf("bad: %s", err)
+	}
+
+	return ls
+}

state/remote/atlas.go

@@ -18,35 +18,18 @@ const (
 	defaultAtlasServer = "https://atlas.hashicorp.com/"
 )
 
-// AtlasRemoteClient implements the RemoteClient interface
+func atlasFactory(conf map[string]string) (Client, error) {
-// for an Atlas compatible server.
+	var client AtlasClient
-type AtlasRemoteClient struct {
-	server      string
-	serverURL   *url.URL
-	user        string
-	name        string
-	accessToken string
-}
 
-func NewAtlasRemoteClient(conf map[string]string) (*AtlasRemoteClient, error) {
-	client := &AtlasRemoteClient{}
-	if err := client.validateConfig(conf); err != nil {
-		return nil, err
-	}
-	return client, nil
-}
-
-func (c *AtlasRemoteClient) validateConfig(conf map[string]string) error {
 	server, ok := conf["address"]
 	if !ok || server == "" {
 		server = defaultAtlasServer
 	}
+
 	url, err := url.Parse(server)
 	if err != nil {
-		return err
+		return nil, err
 	}
-	c.server = server
-	c.serverURL = url
 
 	token, ok := conf["access_token"]
 	if token == "" {
@@ -54,26 +37,39 @@ func (c *AtlasRemoteClient) validateConfig(conf map[string]string) error {
 		ok = true
 	}
 	if !ok || token == "" {
-		return fmt.Errorf(
+		return nil, fmt.Errorf(
 			"missing 'access_token' configuration or ATLAS_TOKEN environmental variable")
 	}
-	c.accessToken = token
 
 	name, ok := conf["name"]
 	if !ok || name == "" {
-		return fmt.Errorf("missing 'name' configuration")
+		return nil, fmt.Errorf("missing 'name' configuration")
 	}
 
 	parts := strings.Split(name, "/")
 	if len(parts) != 2 {
-		return fmt.Errorf("malformed name '%s'", name)
+		return nil, fmt.Errorf("malformed name '%s'", name)
-	}
-	c.user = parts[0]
-	c.name = parts[1]
-	return nil
 	}
 
-func (c *AtlasRemoteClient) GetState() (*RemoteStatePayload, error) {
+	client.Server = server
+	client.ServerURL = url
+	client.AccessToken = token
+	client.User = parts[0]
+	client.Name = parts[1]
+
+	return &client, nil
+}
+
+// AtlasClient implements the Client interface for an Atlas compatible server.
+type AtlasClient struct {
+	Server      string
+	ServerURL   *url.URL
+	User        string
+	Name        string
+	AccessToken string
+}
+
+func (c *AtlasClient) Get() (*Payload, error) {
 	// Make the HTTP request
 	req, err := http.NewRequest("GET", c.url().String(), nil)
 	if err != nil {
@@ -96,11 +92,11 @@ func (c *AtlasRemoteClient) GetState() (*RemoteStatePayload, error) {
 	case http.StatusNotFound:
 		return nil, nil
 	case http.StatusUnauthorized:
-		return nil, ErrRequireAuth
+		return nil, fmt.Errorf("HTTP remote state endpoint requires auth")
 	case http.StatusForbidden:
-		return nil, ErrInvalidAuth
+		return nil, fmt.Errorf("HTTP remote state endpoint invalid auth")
 	case http.StatusInternalServerError:
-		return nil, ErrRemoteInternal
+		return nil, fmt.Errorf("HTTP remote state internal server error")
 	default:
 		return nil, fmt.Errorf("Unexpected HTTP response code %d", resp.StatusCode)
 	}
@@ -112,8 +108,12 @@ func (c *AtlasRemoteClient) GetState() (*RemoteStatePayload, error) {
 	}
 
 	// Create the payload
-	payload := &RemoteStatePayload{
+	payload := &Payload{
-		State: buf.Bytes(),
+		Data: buf.Bytes(),
+	}
+
+	if len(payload.Data) == 0 {
+		return nil, nil
 	}
 
 	// Check for the MD5
@@ -122,18 +122,18 @@ func (c *AtlasRemoteClient) GetState() (*RemoteStatePayload, error) {
 		if err != nil {
 			return nil, fmt.Errorf("Failed to decode Content-MD5 '%s': %v", raw, err)
 		}
-		payload.MD5 = md5
 
+		payload.MD5 = md5
 	} else {
 		// Generate the MD5
-		hash := md5.Sum(payload.State)
+		hash := md5.Sum(payload.Data)
-		payload.MD5 = hash[:md5.Size]
+		payload.MD5 = hash[:]
 	}
 
 	return payload, nil
 }
 
-func (c *AtlasRemoteClient) PutState(state []byte, force bool) error {
+func (c *AtlasClient) Put(state []byte) error {
 	// Get the target URL
 	base := c.url()
 
@@ -141,12 +141,14 @@ func (c *AtlasRemoteClient) PutState(state []byte, force bool) error {
 	hash := md5.Sum(state)
 	b64 := base64.StdEncoding.EncodeToString(hash[:md5.Size])
 
+	/*
 		// Set the force query parameter if needed
 		if force {
 			values := base.Query()
 			values.Set("force", "true")
 			base.RawQuery = values.Encode()
 		}
+	*/
 
 	// Make the HTTP client and request
 	req, err := http.NewRequest("PUT", base.String(), bytes.NewReader(state))
@@ -170,22 +172,12 @@ func (c *AtlasRemoteClient) PutState(state []byte, force bool) error {
 	switch resp.StatusCode {
 	case http.StatusOK:
 		return nil
-	case http.StatusConflict:
-		return ErrConflict
-	case http.StatusPreconditionFailed:
-		return ErrServerNewer
-	case http.StatusUnauthorized:
-		return ErrRequireAuth
-	case http.StatusForbidden:
-		return ErrInvalidAuth
-	case http.StatusInternalServerError:
-		return ErrRemoteInternal
 	default:
-		return fmt.Errorf("Unexpected HTTP response code %d", resp.StatusCode)
+		return fmt.Errorf("HTTP error: %d", resp.StatusCode)
 	}
 }
 
-func (c *AtlasRemoteClient) DeleteState() error {
+func (c *AtlasClient) Delete() error {
 	// Make the HTTP request
 	req, err := http.NewRequest("DELETE", c.url().String(), nil)
 	if err != nil {
@@ -207,22 +199,18 @@ func (c *AtlasRemoteClient) DeleteState() error {
 		return nil
 	case http.StatusNotFound:
 		return nil
-	case http.StatusUnauthorized:
+	default:
-		return ErrRequireAuth
+		return fmt.Errorf("HTTP error: %d", resp.StatusCode)
-	case http.StatusForbidden:
-		return ErrInvalidAuth
-	case http.StatusInternalServerError:
-		return ErrRemoteInternal
 	}
 
 	return fmt.Errorf("Unexpected HTTP response code %d", resp.StatusCode)
 }
 
-func (c *AtlasRemoteClient) url() *url.URL {
+func (c *AtlasClient) url() *url.URL {
 	return &url.URL{
-		Scheme:   c.serverURL.Scheme,
+		Scheme:   c.ServerURL.Scheme,
-		Host:     c.serverURL.Host,
+		Host:     c.ServerURL.Host,
-		Path:     path.Join("api/v1/terraform/state", c.user, c.name),
+		Path:     path.Join("api/v1/terraform/state", c.User, c.Name),
-		RawQuery: fmt.Sprintf("access_token=%s", c.accessToken),
+		RawQuery: fmt.Sprintf("access_token=%s", c.AccessToken),
 	}
 }

state/remote/atlas_test.go

@@ -0,0 +1,32 @@
+package remote
+
+import (
+	"net/http"
+	"os"
+	"testing"
+)
+
+func TestAtlasClient_impl(t *testing.T) {
+	var _ Client = new(AtlasClient)
+}
+
+func TestAtlasClient(t *testing.T) {
+	if _, err := http.Get("http://google.com"); err != nil {
+		t.Skipf("skipping, internet seems to not be available: %s", err)
+	}
+
+	token := os.Getenv("ATLAS_TOKEN")
+	if token == "" {
+		t.Skipf("skipping, ATLAS_TOKEN must be set")
+	}
+
+	client, err := atlasFactory(map[string]string{
+		"access_token": token,
+		"name":         "hashicorp/test-remote-state",
+	})
+	if err != nil {
+		t.Fatalf("bad: %s", err)
+	}
+
+	testClient(t, client)
+}

state/remote/client_inmem.go

@@ -0,0 +1,32 @@
+package remote
+
+import (
+	"crypto/md5"
+)
+
+// InmemClient is a Client implementation that stores data in memory.
+type InmemClient struct {
+	Data []byte
+	MD5  []byte
+}
+
+func (c *InmemClient) Get() (*Payload, error) {
+	return &Payload{
+		Data: c.Data,
+		MD5:  c.MD5,
+	}, nil
+}
+
+func (c *InmemClient) Put(data []byte) error {
+	md5 := md5.Sum(data)
+
+	c.Data = data
+	c.MD5 = md5[:]
+	return nil
+}
+
+func (c *InmemClient) Delete() error {
+	c.Data = nil
+	c.MD5 = nil
+	return nil
+}

state/remote/consul.go

@@ -0,0 +1,70 @@
+package remote
+
+import (
+	"crypto/md5"
+	"fmt"
+
+	consulapi "github.com/hashicorp/consul/api"
+)
+
+func consulFactory(conf map[string]string) (Client, error) {
+	path, ok := conf["path"]
+	if !ok {
+		return nil, fmt.Errorf("missing 'path' configuration")
+	}
+
+	config := consulapi.DefaultConfig()
+	if token, ok := conf["access_token"]; ok && token != "" {
+		config.Token = token
+	}
+	if addr, ok := conf["address"]; ok && addr != "" {
+		config.Address = addr
+	}
+
+	client, err := consulapi.NewClient(config)
+	if err != nil {
+		return nil, err
+	}
+
+	return &ConsulClient{
+		Client: client,
+		Path:   path,
+	}, nil
+}
+
+// ConsulClient is a remote client that stores data in Consul.
+type ConsulClient struct {
+	Client *consulapi.Client
+	Path   string
+}
+
+func (c *ConsulClient) Get() (*Payload, error) {
+	pair, _, err := c.Client.KV().Get(c.Path, nil)
+	if err != nil {
+		return nil, err
+	}
+	if pair == nil {
+		return nil, nil
+	}
+
+	md5 := md5.Sum(pair.Value)
+	return &Payload{
+		Data: pair.Value,
+		MD5:  md5[:],
+	}, nil
+}
+
+func (c *ConsulClient) Put(data []byte) error {
+	kv := c.Client.KV()
+	_, err := kv.Put(&consulapi.KVPair{
+		Key:   c.Path,
+		Value: data,
+	}, nil)
+	return err
+}
+
+func (c *ConsulClient) Delete() error {
+	kv := c.Client.KV()
+	_, err := kv.Delete(c.Path, nil)
+	return err
+}

state/remote/consul_test.go

@@ -0,0 +1,28 @@
+package remote
+
+import (
+	"fmt"
+	"net/http"
+	"testing"
+	"time"
+)
+
+func TestConsulClient_impl(t *testing.T) {
+	var _ Client = new(ConsulClient)
+}
+
+func TestConsulClient(t *testing.T) {
+	if _, err := http.Get("http://google.com"); err != nil {
+		t.Skipf("skipping, internet seems to not be available: %s", err)
+	}
+
+	client, err := consulFactory(map[string]string{
+		"address": "demo.consul.io:80",
+		"path":    fmt.Sprintf("tf-unit/%s", time.Now().String()),
+	})
+	if err != nil {
+		t.Fatalf("bad: %s", err)
+	}
+
+	testClient(t, client)
+}

state/remote/http.go

@@ -0,0 +1,161 @@
+package remote
+
+import (
+	"bytes"
+	"crypto/md5"
+	"encoding/base64"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+)
+
+func httpFactory(conf map[string]string) (Client, error) {
+	address, ok := conf["address"]
+	if !ok {
+		return nil, fmt.Errorf("missing 'address' configuration")
+	}
+
+	url, err := url.Parse(address)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse HTTP URL: %s", err)
+	}
+	if url.Scheme != "http" && url.Scheme != "https" {
+		return nil, fmt.Errorf("address must be HTTP or HTTPS")
+	}
+
+	return &HTTPClient{
+		URL: url,
+	}, nil
+}
+
+// HTTPClient is a remote client that stores data in Consul.
+type HTTPClient struct {
+	URL *url.URL
+}
+
+func (c *HTTPClient) Get() (*Payload, error) {
+	resp, err := http.Get(c.URL.String())
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	// Handle the common status codes
+	switch resp.StatusCode {
+	case http.StatusOK:
+		// Handled after
+	case http.StatusNoContent:
+		return nil, nil
+	case http.StatusNotFound:
+		return nil, nil
+	case http.StatusUnauthorized:
+		return nil, fmt.Errorf("HTTP remote state endpoint requires auth")
+	case http.StatusForbidden:
+		return nil, fmt.Errorf("HTTP remote state endpoint invalid auth")
+	case http.StatusInternalServerError:
+		return nil, fmt.Errorf("HTTP remote state internal server error")
+	default:
+		return nil, fmt.Errorf("Unexpected HTTP response code %d", resp.StatusCode)
+	}
+
+	// Read in the body
+	buf := bytes.NewBuffer(nil)
+	if _, err := io.Copy(buf, resp.Body); err != nil {
+		return nil, fmt.Errorf("Failed to read remote state: %s", err)
+	}
+
+	// Create the payload
+	payload := &Payload{
+		Data: buf.Bytes(),
+	}
+
+	// If there was no data, then return nil
+	if len(payload.Data) == 0 {
+		return nil, nil
+	}
+
+	// Check for the MD5
+	if raw := resp.Header.Get("Content-MD5"); raw != "" {
+		md5, err := base64.StdEncoding.DecodeString(raw)
+		if err != nil {
+			return nil, fmt.Errorf(
+				"Failed to decode Content-MD5 '%s': %s", raw, err)
+		}
+
+		payload.MD5 = md5
+	} else {
+		// Generate the MD5
+		hash := md5.Sum(payload.Data)
+		payload.MD5 = hash[:]
+	}
+
+	return payload, nil
+}
+
+func (c *HTTPClient) Put(data []byte) error {
+	// Copy the target URL
+	base := *c.URL
+
+	// Generate the MD5
+	hash := md5.Sum(data)
+	b64 := base64.StdEncoding.EncodeToString(hash[:])
+
+	/*
+		// Set the force query parameter if needed
+		if force {
+			values := base.Query()
+			values.Set("force", "true")
+			base.RawQuery = values.Encode()
+		}
+	*/
+
+	// Make the HTTP client and request
+	req, err := http.NewRequest("POST", base.String(), bytes.NewReader(data))
+	if err != nil {
+		return fmt.Errorf("Failed to make HTTP request: %s", err)
+	}
+
+	// Prepare the request
+	req.Header.Set("Content-Type", "application/octet-stream")
+	req.Header.Set("Content-MD5", b64)
+	req.ContentLength = int64(len(data))
+
+	// Make the request
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return fmt.Errorf("Failed to upload state: %v", err)
+	}
+	defer resp.Body.Close()
+
+	// Handle the error codes
+	switch resp.StatusCode {
+	case http.StatusOK:
+		return nil
+	default:
+		return fmt.Errorf("HTTP error: %d", resp.StatusCode)
+	}
+}
+
+func (c *HTTPClient) Delete() error {
+	// Make the HTTP request
+	req, err := http.NewRequest("DELETE", c.URL.String(), nil)
+	if err != nil {
+		return fmt.Errorf("Failed to make HTTP request: %s", err)
+	}
+
+	// Make the request
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return fmt.Errorf("Failed to delete state: %s", err)
+	}
+	defer resp.Body.Close()
+
+	// Handle the error codes
+	switch resp.StatusCode {
+	case http.StatusOK:
+		return nil
+	default:
+		return fmt.Errorf("HTTP error: %d", resp.StatusCode)
+	}
+}

state/remote/http_test.go

@@ -0,0 +1,53 @@
+package remote
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"testing"
+)
+
+func TestHTTPClient_impl(t *testing.T) {
+	var _ Client = new(HTTPClient)
+}
+
+func TestHTTPClient(t *testing.T) {
+	handler := new(testHTTPHandler)
+	ts := httptest.NewServer(http.HandlerFunc(handler.Handle))
+	defer ts.Close()
+
+	url, err := url.Parse(ts.URL)
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	client := &HTTPClient{URL: url}
+	testClient(t, client)
+}
+
+type testHTTPHandler struct {
+	Data []byte
+}
+
+func (h *testHTTPHandler) Handle(w http.ResponseWriter, r *http.Request) {
+	switch r.Method {
+	case "GET":
+		w.Write(h.Data)
+	case "POST":
+		buf := new(bytes.Buffer)
+		if _, err := io.Copy(buf, r.Body); err != nil {
+			w.WriteHeader(500)
+		}
+
+		h.Data = buf.Bytes()
+	case "DELETE":
+		h.Data = nil
+		w.WriteHeader(200)
+	default:
+		w.WriteHeader(500)
+		w.Write([]byte(fmt.Sprintf("Unknown method: %s", r.Method)))
+	}
+}

state/remote/remote.go

@@ -0,0 +1,42 @@
+package remote
+
+import (
+	"fmt"
+)
+
+// Client is the interface that must be implemented for a remote state
+// driver. It supports dumb put/get/delete, and the higher level structs
+// handle persisting the state properly here.
+type Client interface {
+	Get() (*Payload, error)
+	Put([]byte) error
+	Delete() error
+}
+
+// Payload is the return value from the remote state storage.
+type Payload struct {
+	MD5  []byte
+	Data []byte
+}
+
+// Factory is the factory function to create a remote client.
+type Factory func(map[string]string) (Client, error)
+
+// NewClient returns a new Client with the given type and configuration.
+// The client is looked up in the BuiltinClients variable.
+func NewClient(t string, conf map[string]string) (Client, error) {
+	f, ok := BuiltinClients[t]
+	if !ok {
+		return nil, fmt.Errorf("unknown remote client type: %s", t)
+	}
+
+	return f(conf)
+}
+
+// BuiltinClients is the list of built-in clients that can be used with
+// NewClient.
+var BuiltinClients = map[string]Factory{
+	"atlas":  atlasFactory,
+	"consul": consulFactory,
+	"http":   httpFactory,
+}

state/remote/remote_test.go

@@ -0,0 +1,35 @@
+package remote
+
+import (
+	"bytes"
+	"testing"
+)
+
+// testClient is a generic function to test any client.
+func testClient(t *testing.T, c Client) {
+	data := []byte("foo")
+
+	if err := c.Put(data); err != nil {
+		t.Fatalf("put: %s", err)
+	}
+
+	p, err := c.Get()
+	if err != nil {
+		t.Fatalf("get: %s", err)
+	}
+	if !bytes.Equal(p.Data, data) {
+		t.Fatalf("bad: %#v", p)
+	}
+
+	if err := c.Delete(); err != nil {
+		t.Fatalf("delete: %s", err)
+	}
+
+	p, err = c.Get()
+	if err != nil {
+		t.Fatalf("get: %s", err)
+	}
+	if p != nil {
+		t.Fatalf("bad: %#v", p)
+	}
+}

state/remote/state.go

@@ -0,0 +1,57 @@
+package remote
+
+import (
+	"bytes"
+
+	"github.com/hashicorp/terraform/terraform"
+)
+
+// State implements the State interfaces in the state package to handle
+// reading and writing the remote state. This State on its own does no
+// local caching so every persist will go to the remote storage and local
+// writes will go to memory.
+type State struct {
+	Client Client
+
+	state *terraform.State
+}
+
+// StateReader impl.
+func (s *State) State() *terraform.State {
+	return s.state
+}
+
+// StateWriter impl.
+func (s *State) WriteState(state *terraform.State) error {
+	s.state = state
+	return nil
+}
+
+// StateRefresher impl.
+func (s *State) RefreshState() error {
+	payload, err := s.Client.Get()
+	if err != nil {
+		return err
+	}
+
+	var state *terraform.State
+	if payload != nil {
+		state, err = terraform.ReadState(bytes.NewReader(payload.Data))
+		if err != nil {
+			return err
+		}
+	}
+
+	s.state = state
+	return nil
+}
+
+// StatePersister impl.
+func (s *State) PersistState() error {
+	var buf bytes.Buffer
+	if err := terraform.WriteState(s.state, &buf); err != nil {
+		return err
+	}
+
+	return s.Client.Put(buf.Bytes())
+}

state/remote/state_test.go

@@ -0,0 +1,24 @@
+package remote
+
+import (
+	"testing"
+
+	"github.com/hashicorp/terraform/state"
+)
+
+func TestState(t *testing.T) {
+	s := &State{Client: new(InmemClient)}
+	s.WriteState(state.TestStateInitial())
+	if err := s.PersistState(); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	state.TestState(t, s)
+}
+
+func TestState_impl(t *testing.T) {
+	var _ state.StateReader = new(State)
+	var _ state.StateWriter = new(State)
+	var _ state.StatePersister = new(State)
+	var _ state.StateRefresher = new(State)
+}

state/state.go

@@ -0,0 +1,42 @@
+package state
+
+import (
+	"github.com/hashicorp/terraform/terraform"
+)
+
+// State is the collection of all state interfaces.
+type State interface {
+	StateReader
+	StateWriter
+	StateRefresher
+	StatePersister
+}
+
+// StateReader is the interface for things that can return a state. Retrieving
+// the state here must not error. Loading the state fresh (an operation that
+// can likely error) should be implemented by RefreshState. If a state hasn't
+// been loaded yet, it is okay for State to return nil.
+type StateReader interface {
+	State() *terraform.State
+}
+
+// StateWriter is the interface that must be implemented by something that
+// can write a state. Writing the state can be cached or in-memory, as
+// full persistence should be implemented by StatePersister.
+type StateWriter interface {
+	WriteState(*terraform.State) error
+}
+
+// StateRefresher is the interface that is implemented by something that
+// can load a state. This might be refreshing it from a remote location or
+// it might simply be reloading it from disk.
+type StateRefresher interface {
+	RefreshState() error
+}
+
+// StatePersister is implemented to truly persist a state. Whereas StateWriter
+// is allowed to perhaps be caching in memory, PersistState must write the
+// state to some durable storage.
+type StatePersister interface {
+	PersistState() error
+}

state/testing.go

@@ -0,0 +1,94 @@
+package state
+
+import (
+	"bytes"
+	"reflect"
+	"testing"
+
+	"github.com/hashicorp/terraform/terraform"
+)
+
+// TestState is a helper for testing state implementations. It is expected
+// that the given implementation is pre-loaded with the TestStateInitial
+// state.
+func TestState(t *testing.T, s interface{}) {
+	reader, ok := s.(StateReader)
+	if !ok {
+		t.Fatalf("must at least be a StateReader")
+	}
+
+	// If it implements refresh, refresh
+	if rs, ok := s.(StateRefresher); ok {
+		if err := rs.RefreshState(); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+	}
+
+	// current will track our current state
+	current := TestStateInitial()
+
+	// Check that the initial state is correct
+	state := reader.State()
+	current.Serial = state.Serial
+	if !reflect.DeepEqual(state, current) {
+		t.Fatalf("not initial: %#v\n\n%#v", state, current)
+	}
+
+	// Write a new state and verify that we have it
+	if ws, ok := s.(StateWriter); ok {
+		current.Modules = append(current.Modules, &terraform.ModuleState{
+			Path: []string{"root"},
+			Outputs: map[string]string{
+				"bar": "baz",
+			},
+		})
+
+		if err := ws.WriteState(current); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+
+		if actual := reader.State(); !reflect.DeepEqual(actual, current) {
+			t.Fatalf("bad: %#v\n\n%#v", actual, current)
+		}
+	}
+
+	// Test persistence
+	if ps, ok := s.(StatePersister); ok {
+		if err := ps.PersistState(); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+
+		// Refresh if we got it
+		if rs, ok := s.(StateRefresher); ok {
+			if err := rs.RefreshState(); err != nil {
+				t.Fatalf("err: %s", err)
+			}
+		}
+
+		// Just set the serials the same... Then compare.
+		actual := reader.State()
+		actual.Serial = current.Serial
+		if !reflect.DeepEqual(actual, current) {
+			t.Fatalf("bad: %#v\n\n%#v", actual, current)
+		}
+	}
+}
+
+// TestStateInitial is the initial state that a State should have
+// for TestState.
+func TestStateInitial() *terraform.State {
+	initial := &terraform.State{
+		Modules: []*terraform.ModuleState{
+			&terraform.ModuleState{
+				Path: []string{"root", "child"},
+				Outputs: map[string]string{
+					"foo": "bar",
+				},
+			},
+		},
+	}
+
+	var scratch bytes.Buffer
+	terraform.WriteState(initial, &scratch)
+	return initial
+}

terraform/state.go

@@ -125,6 +125,31 @@ func (s *State) ModuleOrphans(path []string, c *config.Config) [][]string {
 	return orphans
 }
 
+// Empty returns true if the state is empty.
+func (s *State) Empty() bool {
+	if s == nil {
+		return true
+	}
+
+	return len(s.Modules) == 0
+}
+
+// IsRemote returns true if State represents a state that exists and is
+// remote.
+func (s *State) IsRemote() bool {
+	if s == nil {
+		return false
+	}
+	if s.Remote == nil {
+		return false
+	}
+	if s.Remote.Type == "" {
+		return false
+	}
+
+	return true
+}
+
 // RootModule returns the ModuleState for the root module
 func (s *State) RootModule() *ModuleState {
 	root := s.ModuleByPath(rootModulePath)
@@ -266,7 +291,7 @@ func (r *RemoteState) deepcopy() *RemoteState {
 }
 
 func (r *RemoteState) Empty() bool {
-	return r.Type == "" && len(r.Config) == 0
+	return r == nil || r.Type == ""
 }
 
 func (r *RemoteState) Equals(other *RemoteState) bool {

terraform/state_test.go

@@ -312,6 +312,70 @@ func TestInstanceStateEqual(t *testing.T) {
 	}
 }
 
+func TestStateEmpty(t *testing.T) {
+	cases := []struct {
+		In     *State
+		Result bool
+	}{
+		{
+			nil,
+			true,
+		},
+		{
+			&State{},
+			true,
+		},
+		{
+			&State{
+				Remote: &RemoteState{Type: "foo"},
+			},
+			true,
+		},
+		{
+			&State{
+				Modules: []*ModuleState{
+					&ModuleState{},
+				},
+			},
+			false,
+		},
+	}
+
+	for i, tc := range cases {
+		if tc.In.Empty() != tc.Result {
+			t.Fatalf("bad %d %#v:\n\n%#v", i, tc.Result, tc.In)
+		}
+	}
+}
+
+func TestStateIsRemote(t *testing.T) {
+	cases := []struct {
+		In     *State
+		Result bool
+	}{
+		{
+			nil,
+			false,
+		},
+		{
+			&State{},
+			false,
+		},
+		{
+			&State{
+				Remote: &RemoteState{Type: "foo"},
+			},
+			true,
+		},
+	}
+
+	for i, tc := range cases {
+		if tc.In.IsRemote() != tc.Result {
+			t.Fatalf("bad %d %#v:\n\n%#v", i, tc.Result, tc.In)
+		}
+	}
+}
+
 func TestInstanceState_MergeDiff(t *testing.T) {
 	is := InstanceState{
 		ID: "foo",