core: module targeting

Adds the ability to target resources within modules, like:

module.mymod.aws_instance.foo

And the ability to target all resources inside a module, like:

module.mymod

Closes #1434

terraform/context_test.go

@@ -6128,6 +6128,87 @@ aws_instance.foo.1:
 	`)
 }
 
+func TestContext2Apply_targetedModule(t *testing.T) {
+	m := testModule(t, "apply-targeted-module")
+	p := testProvider("aws")
+	p.ApplyFn = testApplyFn
+	p.DiffFn = testDiffFn
+	ctx := testContext2(t, &ContextOpts{
+		Module: m,
+		Providers: map[string]ResourceProviderFactory{
+			"aws": testProviderFuncFixed(p),
+		},
+		Targets: []string{"module.child"},
+	})
+
+	if _, err := ctx.Plan(); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	state, err := ctx.Apply()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	mod := state.ModuleByPath([]string{"root", "child"})
+	if mod == nil {
+		t.Fatalf("no child module found in the state!\n\n%#v", state)
+	}
+	if len(mod.Resources) != 2 {
+		t.Fatalf("expected 2 resources, got: %#v", mod.Resources)
+	}
+
+	checkStateString(t, state, `
+<no state>
+module.child:
+  aws_instance.bar:
+    ID = foo
+    num = 2
+    type = aws_instance
+  aws_instance.foo:
+    ID = foo
+    num = 2
+    type = aws_instance
+	`)
+}
+
+func TestContext2Apply_targetedModuleResource(t *testing.T) {
+	m := testModule(t, "apply-targeted-module-resource")
+	p := testProvider("aws")
+	p.ApplyFn = testApplyFn
+	p.DiffFn = testDiffFn
+	ctx := testContext2(t, &ContextOpts{
+		Module: m,
+		Providers: map[string]ResourceProviderFactory{
+			"aws": testProviderFuncFixed(p),
+		},
+		Targets: []string{"module.child.aws_instance.foo"},
+	})
+
+	if _, err := ctx.Plan(); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	state, err := ctx.Apply()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	mod := state.ModuleByPath([]string{"root", "child"})
+	if len(mod.Resources) != 1 {
+		t.Fatalf("expected 1 resource, got: %#v", mod.Resources)
+	}
+
+	checkStateString(t, state, `
+<no state>
+module.child:
+  aws_instance.foo:
+    ID = foo
+    num = 2
+    type = aws_instance
+	`)
+}
+
 func TestContext2Apply_unknownAttribute(t *testing.T) {
 	m := testModule(t, "apply-unknown")
 	p := testProvider("aws")

terraform/graph_config_node_resource.go

@@ -19,6 +19,8 @@ type GraphNodeConfigResource struct {
 
 	// Used during DynamicExpand to target indexes
 	Targets []ResourceAddress
+
+	Path []string
 }
 
 func (n *GraphNodeConfigResource) ConfigType() GraphNodeConfigType {
@@ -174,7 +176,7 @@ func (n *GraphNodeConfigResource) DynamicExpand(ctx EvalContext) (*Graph, error)
 // GraphNodeAddressable impl.
 func (n *GraphNodeConfigResource) ResourceAddress() *ResourceAddress {
 	return &ResourceAddress{
-		// Indicates no specific index; will match on other three fields
+		Path:         n.Path[1:],
 		Index:        -1,
 		InstanceType: TypePrimary,
 		Name:         n.Resource.Name,

terraform/resource_address.go

@@ -2,14 +2,22 @@ package terraform
 
 import (
 	"fmt"
+	"reflect"
 	"regexp"
 	"strconv"
+	"strings"
 )
 
 // ResourceAddress is a way of identifying an individual resource (or,
 // eventually, a subset of resources) within the state. It is used for Targets.
 type ResourceAddress struct {
-	Index        int
+	// Addresses a resource falling somewhere in the module path
+	// When specified alone, addresses all resources within a module path
+	Path []string
+
+	// Addresses a specific resource that occurs in a list
+	Index int
+
 	InstanceType InstanceType
 	Name         string
 	Type         string
@@ -20,22 +28,18 @@ func ParseResourceAddress(s string) (*ResourceAddress, error) {
 	if err != nil {
 		return nil, err
 	}
-	resourceIndex := -1
-	if matches["index"] != "" {
-		var err error
-		if resourceIndex, err = strconv.Atoi(matches["index"]); err != nil {
-			return nil, err
-		}
+	resourceIndex, err := ParseResourceIndex(matches["index"])
+	if err != nil {
+		return nil, err
 	}
-	instanceType := TypePrimary
-	if matches["instance_type"] != "" {
-		var err error
-		if instanceType, err = ParseInstanceType(matches["instance_type"]); err != nil {
-			return nil, err
-		}
+	instanceType, err := ParseInstanceType(matches["instance_type"])
+	if err != nil {
+		return nil, err
 	}
+	path := ParseResourcePath(matches["path"])
 
 	return &ResourceAddress{
+		Path:         path,
 		Index:        resourceIndex,
 		InstanceType: instanceType,
 		Name:         matches["name"],
@@ -49,19 +53,55 @@ func (addr *ResourceAddress) Equals(raw interface{}) bool {
 		return false
 	}
 
+	pathMatch := ((len(addr.Path) == 0 && len(other.Path) == 0) ||
+		reflect.DeepEqual(addr.Path, other.Path))
+
 	indexMatch := (addr.Index == -1 ||
 		other.Index == -1 ||
 		addr.Index == other.Index)
 
-	return (indexMatch &&
-		addr.InstanceType == other.InstanceType &&
-		addr.Name == other.Name &&
+	nameMatch := (addr.Name == "" ||
+		other.Name == "" ||
+		addr.Name == other.Name)
+
+	typeMatch := (addr.Type == "" ||
+		other.Type == "" ||
 		addr.Type == other.Type)
+
+	return (pathMatch &&
+		indexMatch &&
+		addr.InstanceType == other.InstanceType &&
+		nameMatch &&
+		typeMatch)
+}
+
+func ParseResourceIndex(s string) (int, error) {
+	if s == "" {
+		return -1, nil
+	}
+	return strconv.Atoi(s)
+}
+
+func ParseResourcePath(s string) []string {
+	if s == "" {
+		return nil
+	}
+	parts := strings.Split(s, ".")
+	path := make([]string, 0, len(parts))
+	for _, s := range parts {
+		// Due to the limitations of the regexp match below, the path match has
+		// some noise in it we have to filter out :|
+		if s == "" || s == "module" {
+			continue
+		}
+		path = append(path, s)
+	}
+	return path
 }
 
 func ParseInstanceType(s string) (InstanceType, error) {
 	switch s {
-	case "primary":
+	case "", "primary":
 		return TypePrimary, nil
 	case "deposed":
 		return TypeDeposed, nil
@@ -76,10 +116,10 @@ func tokenizeResourceAddress(s string) (map[string]string, error) {
 	// Example of portions of the regexp below using the
 	// string "aws_instance.web.tainted[1]"
 	re := regexp.MustCompile(`\A` +
-		// "aws_instance"
-		`(?P<type>[^.]+)\.` +
-		// "web"
-		`(?P<name>[^.[]+)` +
+		// "module.foo.module.bar" (optional)
+		`(?P<path>(?:module\.[^.]+\.?)*)` +
+		// "aws_instance.web" (optional when module path specified)
+		`(?:(?P<type>[^.]+)\.(?P<name>[^.[]+))?` +
 		// "tainted" (optional, omission implies: "primary")
 		`(?:\.(?P<instance_type>\w+))?` +
 		// "1" (optional, omission implies: "0")

terraform/resource_address_test.go

@@ -64,6 +64,46 @@ func TestParseResourceAddress(t *testing.T) {
 				Index:        -1,
 			},
 		},
+		"in a module": {
+			Input: "module.child.aws_instance.foo",
+			Expected: &ResourceAddress{
+				Path:         []string{"child"},
+				Type:         "aws_instance",
+				Name:         "foo",
+				InstanceType: TypePrimary,
+				Index:        -1,
+			},
+		},
+		"nested modules": {
+			Input: "module.a.module.b.module.forever.aws_instance.foo",
+			Expected: &ResourceAddress{
+				Path:         []string{"a", "b", "forever"},
+				Type:         "aws_instance",
+				Name:         "foo",
+				InstanceType: TypePrimary,
+				Index:        -1,
+			},
+		},
+		"just a module": {
+			Input: "module.a",
+			Expected: &ResourceAddress{
+				Path:         []string{"a"},
+				Type:         "",
+				Name:         "",
+				InstanceType: TypePrimary,
+				Index:        -1,
+			},
+		},
+		"just a nested module": {
+			Input: "module.a.module.b",
+			Expected: &ResourceAddress{
+				Path:         []string{"a", "b"},
+				Type:         "",
+				Name:         "",
+				InstanceType: TypePrimary,
+				Index:        -1,
+			},
+		},
 	}
 
 	for tn, tc := range cases {
@@ -204,6 +244,57 @@ func TestResourceAddressEquals(t *testing.T) {
 			},
 			Expect: false,
 		},
+		"module address matches address of resource inside module": {
+			Address: &ResourceAddress{
+				Path:         []string{"a", "b"},
+				Type:         "",
+				Name:         "",
+				InstanceType: TypePrimary,
+				Index:        -1,
+			},
+			Other: &ResourceAddress{
+				Path:         []string{"a", "b"},
+				Type:         "aws_instance",
+				Name:         "foo",
+				InstanceType: TypePrimary,
+				Index:        0,
+			},
+			Expect: true,
+		},
+		"module address doesn't match resource outside module": {
+			Address: &ResourceAddress{
+				Path:         []string{"a", "b"},
+				Type:         "",
+				Name:         "",
+				InstanceType: TypePrimary,
+				Index:        -1,
+			},
+			Other: &ResourceAddress{
+				Path:         []string{"a"},
+				Type:         "aws_instance",
+				Name:         "foo",
+				InstanceType: TypePrimary,
+				Index:        0,
+			},
+			Expect: false,
+		},
+		"nil path vs empty path should match": {
+			Address: &ResourceAddress{
+				Path:         []string{},
+				Type:         "aws_instance",
+				Name:         "foo",
+				InstanceType: TypePrimary,
+				Index:        -1,
+			},
+			Other: &ResourceAddress{
+				Path:         nil,
+				Type:         "aws_instance",
+				Name:         "foo",
+				InstanceType: TypePrimary,
+				Index:        0,
+			},
+			Expect: true,
+		},
 	}
 
 	for tn, tc := range cases {

terraform/test-fixtures/apply-targeted-module-resource/child/main.tf

@@ -0,0 +1,7 @@
+resource "aws_instance" "foo" {
+    num = "2"
+}
+
+resource "aws_instance" "bar" {
+    num = "2"
+}

terraform/test-fixtures/apply-targeted-module-resource/main.tf

@@ -0,0 +1,7 @@
+module "child" {
+    source = "./child"
+}
+
+resource "aws_instance" "bar" {
+    foo = "bar"
+}

terraform/test-fixtures/apply-targeted-module/child/main.tf

@@ -0,0 +1,7 @@
+resource "aws_instance" "foo" {
+    num = "2"
+}
+
+resource "aws_instance" "bar" {
+    num = "2"
+}

terraform/test-fixtures/apply-targeted-module/main.tf

@@ -0,0 +1,11 @@
+module "child" {
+    source = "./child"
+}
+
+resource "aws_instance" "foo" {
+    foo = "bar"
+}
+
+resource "aws_instance" "bar" {
+    foo = "bar"
+}

terraform/transform_config.go

@@ -55,7 +55,10 @@ func (t *ConfigTransformer) Transform(g *Graph) error {
 
 	// Write all the resources out
 	for _, r := range config.Resources {
-		nodes = append(nodes, &GraphNodeConfigResource{Resource: r})
+		nodes = append(nodes, &GraphNodeConfigResource{
+			Resource: r,
+			Path:     g.Path,
+		})
 	}
 
 	// Write all the modules out

terraform/transform_resource.go

@@ -44,6 +44,7 @@ func (t *ResourceCountTransformer) Transform(g *Graph) error {
 		var node dag.Vertex = &graphNodeExpandedResource{
 			Index:    index,
 			Resource: t.Resource,
+			Path:     g.Path,
 		}
 		if t.Destroy {
 			node = &graphNodeExpandedResourceDestroy{
@@ -93,6 +94,7 @@ func (t *ResourceCountTransformer) nodeIsTargeted(node dag.Vertex) bool {
 type graphNodeExpandedResource struct {
 	Index    int
 	Resource *config.Resource
+	Path     []string
 }
 
 func (n *graphNodeExpandedResource) Name() string {
@@ -112,8 +114,8 @@ func (n *graphNodeExpandedResource) ResourceAddress() *ResourceAddress {
 		index = 0
 	}
 	return &ResourceAddress{
-		Index: index,
-		// TODO: kjkjkj
+		Path:         n.Path[1:],
+		Index:        index,
 		InstanceType: TypePrimary,
 		Name:         n.Resource.Name,
 		Type:         n.Resource.Type,

terraform/transform_targets.go

@@ -1,6 +1,10 @@
 package terraform
 
-import "github.com/hashicorp/terraform/dag"
+import (
+	"log"
+
+	"github.com/hashicorp/terraform/dag"
+)
 
 // TargetsTransformer is a GraphTransformer that, when the user specifies a
 // list of resources to target, limits the graph to only those resources and
@@ -30,6 +34,7 @@ func (t *TargetsTransformer) Transform(g *Graph) error {
 		for _, v := range g.Vertices() {
 			if _, ok := v.(GraphNodeAddressable); ok {
 				if !targetedNodes.Include(v) {
+					log.Printf("[DEBUG] Removing %s, filtered by targeting.", v)
 					g.Remove(v)
 				}
 			}

website/source/docs/internals/resource-addressing.html.markdown

@@ -10,19 +10,34 @@ description: |-
 # Resource Addressing
 
 A __Resource Address__ is a string that references a specific resource in a
-larger infrastructure. The syntax of a resource address is:
+larger infrastructure. An address is made up of two parts:
 
 ```
-<resource_type>.<resource_name>[optional fields]
+[module path][resource spec]
 ```
 
-Required fields:
+__Module path__:
+
+A module path addresses a module within the tree of modules. It takes the form:
+
+```
+module.A.module.B.module.C...
+```
+
+Multiple modules in a path indicate nesting. If a module path is specified
+without a resource spec, the address applies to every resource within the
+module. If the module path is omitted, this addresses the root module.
+
+__Resource spec__:
+
+A resource spec addresses a specific resource in the config. It takes the form:
+
+```
+resource_type.resource_name[N]
+```
 
  * `resource_type` - Type of the resource being addressed.
  * `resource_name` - User-defined name of the resource.
-
-Optional fields may include:
-
  * `[N]` - where `N` is a `0`-based index into a resource with multiple
    instances specified by the `count` meta-parameter. Omitting an index when
    addressing a resource where `count > 1` means that the address references