533 lines
16 KiB
Go
533 lines
16 KiB
Go
package command
|
|
|
|
import (
|
|
"context"
|
|
"errors"
|
|
"fmt"
|
|
"io/ioutil"
|
|
"os"
|
|
"path/filepath"
|
|
"sort"
|
|
"strings"
|
|
|
|
"github.com/hashicorp/terraform/backend"
|
|
"github.com/hashicorp/terraform/command/clistate"
|
|
"github.com/hashicorp/terraform/state"
|
|
"github.com/hashicorp/terraform/states"
|
|
"github.com/hashicorp/terraform/states/statemgr"
|
|
"github.com/hashicorp/terraform/terraform"
|
|
)
|
|
|
|
type backendMigrateOpts struct {
|
|
OneType, TwoType string
|
|
One, Two backend.Backend
|
|
|
|
// Fields below are set internally when migrate is called
|
|
|
|
oneEnv string // source env
|
|
twoEnv string // dest env
|
|
force bool // if true, won't ask for confirmation
|
|
}
|
|
|
|
// backendMigrateState handles migrating (copying) state from one backend
|
|
// to another. This function handles asking the user for confirmation
|
|
// as well as the copy itself.
|
|
//
|
|
// This function can handle all scenarios of state migration regardless
|
|
// of the existence of state in either backend.
|
|
//
|
|
// After migrating the state, the existing state in the first backend
|
|
// remains untouched.
|
|
//
|
|
// This will attempt to lock both states for the migration.
|
|
func (m *Meta) backendMigrateState(opts *backendMigrateOpts) error {
|
|
// We need to check what the named state status is. If we're converting
|
|
// from multi-state to single-state for example, we need to handle that.
|
|
var oneSingle, twoSingle bool
|
|
oneStates, err := opts.One.Workspaces()
|
|
if err == backend.ErrWorkspacesNotSupported {
|
|
oneSingle = true
|
|
err = nil
|
|
}
|
|
if err != nil {
|
|
return fmt.Errorf(strings.TrimSpace(
|
|
errMigrateLoadStates), opts.OneType, err)
|
|
}
|
|
|
|
_, err = opts.Two.Workspaces()
|
|
if err == backend.ErrWorkspacesNotSupported {
|
|
twoSingle = true
|
|
err = nil
|
|
}
|
|
if err != nil {
|
|
return fmt.Errorf(strings.TrimSpace(
|
|
errMigrateLoadStates), opts.TwoType, err)
|
|
}
|
|
|
|
// Setup defaults
|
|
opts.oneEnv = backend.DefaultStateName
|
|
opts.twoEnv = backend.DefaultStateName
|
|
opts.force = m.forceInitCopy
|
|
|
|
// Determine migration behavior based on whether the source/destination
|
|
// supports multi-state.
|
|
switch {
|
|
// Single-state to single-state. This is the easiest case: we just
|
|
// copy the default state directly.
|
|
case oneSingle && twoSingle:
|
|
return m.backendMigrateState_s_s(opts)
|
|
|
|
// Single-state to multi-state. This is easy since we just copy
|
|
// the default state and ignore the rest in the destination.
|
|
case oneSingle && !twoSingle:
|
|
return m.backendMigrateState_s_s(opts)
|
|
|
|
// Multi-state to single-state. If the source has more than the default
|
|
// state this is complicated since we have to ask the user what to do.
|
|
case !oneSingle && twoSingle:
|
|
// If the source only has one state and it is the default,
|
|
// treat it as if it doesn't support multi-state.
|
|
if len(oneStates) == 1 && oneStates[0] == backend.DefaultStateName {
|
|
return m.backendMigrateState_s_s(opts)
|
|
}
|
|
|
|
return m.backendMigrateState_S_s(opts)
|
|
|
|
// Multi-state to multi-state. We merge the states together (migrating
|
|
// each from the source to the destination one by one).
|
|
case !oneSingle && !twoSingle:
|
|
// If the source only has one state and it is the default,
|
|
// treat it as if it doesn't support multi-state.
|
|
if len(oneStates) == 1 && oneStates[0] == backend.DefaultStateName {
|
|
return m.backendMigrateState_s_s(opts)
|
|
}
|
|
|
|
return m.backendMigrateState_S_S(opts)
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
//-------------------------------------------------------------------
|
|
// State Migration Scenarios
|
|
//
|
|
// The functions below cover handling all the various scenarios that
|
|
// can exist when migrating state. They are named in an immediately not
|
|
// obvious format but is simple:
|
|
//
|
|
// Format: backendMigrateState_s1_s2[_suffix]
|
|
//
|
|
// When s1 or s2 is lower case, it means that it is a single state backend.
|
|
// When either is uppercase, it means that state is a multi-state backend.
|
|
// The suffix is used to disambiguate multiple cases with the same type of
|
|
// states.
|
|
//
|
|
//-------------------------------------------------------------------
|
|
|
|
// Multi-state to multi-state.
|
|
func (m *Meta) backendMigrateState_S_S(opts *backendMigrateOpts) error {
|
|
// Ask the user if they want to migrate their existing remote state
|
|
migrate, err := m.confirm(&terraform.InputOpts{
|
|
Id: "backend-migrate-multistate-to-multistate",
|
|
Query: fmt.Sprintf(
|
|
"Do you want to migrate all workspaces to %q?",
|
|
opts.TwoType),
|
|
Description: fmt.Sprintf(
|
|
strings.TrimSpace(inputBackendMigrateMultiToMulti),
|
|
opts.OneType, opts.TwoType),
|
|
})
|
|
if err != nil {
|
|
return fmt.Errorf(
|
|
"Error asking for state migration action: %s", err)
|
|
}
|
|
if !migrate {
|
|
return fmt.Errorf("Migration aborted by user.")
|
|
}
|
|
|
|
// Read all the states
|
|
oneStates, err := opts.One.Workspaces()
|
|
if err != nil {
|
|
return fmt.Errorf(strings.TrimSpace(
|
|
errMigrateLoadStates), opts.OneType, err)
|
|
}
|
|
|
|
// Sort the states so they're always copied alphabetically
|
|
sort.Strings(oneStates)
|
|
|
|
// Go through each and migrate
|
|
for _, name := range oneStates {
|
|
// Copy the same names
|
|
opts.oneEnv = name
|
|
opts.twoEnv = name
|
|
|
|
// Force it, we confirmed above
|
|
opts.force = true
|
|
|
|
// Perform the migration
|
|
if err := m.backendMigrateState_s_s(opts); err != nil {
|
|
return fmt.Errorf(strings.TrimSpace(
|
|
errMigrateMulti), name, opts.OneType, opts.TwoType, err)
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// Multi-state to single state.
|
|
func (m *Meta) backendMigrateState_S_s(opts *backendMigrateOpts) error {
|
|
currentEnv := m.Workspace()
|
|
|
|
migrate := opts.force
|
|
if !migrate {
|
|
var err error
|
|
// Ask the user if they want to migrate their existing remote state
|
|
migrate, err = m.confirm(&terraform.InputOpts{
|
|
Id: "backend-migrate-multistate-to-single",
|
|
Query: fmt.Sprintf(
|
|
"Destination state %q doesn't support workspaces.\n"+
|
|
"Do you want to copy only your current workspace?",
|
|
opts.TwoType),
|
|
Description: fmt.Sprintf(
|
|
strings.TrimSpace(inputBackendMigrateMultiToSingle),
|
|
opts.OneType, opts.TwoType, currentEnv),
|
|
})
|
|
if err != nil {
|
|
return fmt.Errorf(
|
|
"Error asking for state migration action: %s", err)
|
|
}
|
|
}
|
|
|
|
if !migrate {
|
|
return fmt.Errorf("Migration aborted by user.")
|
|
}
|
|
|
|
// Copy the default state
|
|
opts.oneEnv = currentEnv
|
|
|
|
// now switch back to the default env so we can acccess the new backend
|
|
m.SetWorkspace(backend.DefaultStateName)
|
|
|
|
return m.backendMigrateState_s_s(opts)
|
|
}
|
|
|
|
// Single state to single state, assumed default state name.
|
|
func (m *Meta) backendMigrateState_s_s(opts *backendMigrateOpts) error {
|
|
stateOne, err := opts.One.StateMgr(opts.oneEnv)
|
|
if err != nil {
|
|
return fmt.Errorf(strings.TrimSpace(
|
|
errMigrateSingleLoadDefault), opts.OneType, err)
|
|
}
|
|
if err := stateOne.RefreshState(); err != nil {
|
|
return fmt.Errorf(strings.TrimSpace(
|
|
errMigrateSingleLoadDefault), opts.OneType, err)
|
|
}
|
|
|
|
// Do not migrate workspaces without state.
|
|
if stateOne.State().Empty() {
|
|
return nil
|
|
}
|
|
|
|
stateTwo, err := opts.Two.StateMgr(opts.twoEnv)
|
|
if err == backend.ErrDefaultWorkspaceNotSupported {
|
|
// If the backend doesn't support using the default state, we ask the user
|
|
// for a new name and migrate the default state to the given named state.
|
|
stateTwo, err = func() (statemgr.Full, error) {
|
|
name, err := m.UIInput().Input(&terraform.InputOpts{
|
|
Id: "new-state-name",
|
|
Query: fmt.Sprintf(
|
|
"[reset][bold][yellow]The %q backend configuration only allows "+
|
|
"named workspaces![reset]",
|
|
opts.TwoType),
|
|
Description: strings.TrimSpace(inputBackendNewWorkspaceName),
|
|
})
|
|
if err != nil {
|
|
return nil, fmt.Errorf("Error asking for new state name: %s", err)
|
|
}
|
|
|
|
// Update the name of the target state.
|
|
opts.twoEnv = name
|
|
|
|
stateTwo, err := opts.Two.StateMgr(opts.twoEnv)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
// If the currently selected workspace is the default workspace, then set
|
|
// the named workspace as the new selected workspace.
|
|
if m.Workspace() == backend.DefaultStateName {
|
|
if err := m.SetWorkspace(opts.twoEnv); err != nil {
|
|
return nil, fmt.Errorf("Failed to set new workspace: %s", err)
|
|
}
|
|
}
|
|
|
|
return stateTwo, nil
|
|
}()
|
|
}
|
|
if err != nil {
|
|
return fmt.Errorf(strings.TrimSpace(
|
|
errMigrateSingleLoadDefault), opts.TwoType, err)
|
|
}
|
|
if err := stateTwo.RefreshState(); err != nil {
|
|
return fmt.Errorf(strings.TrimSpace(
|
|
errMigrateSingleLoadDefault), opts.TwoType, err)
|
|
}
|
|
|
|
// Check if we need migration at all.
|
|
// This is before taking a lock, because they may also correspond to the same lock.
|
|
one := stateOne.State()
|
|
two := stateTwo.State()
|
|
|
|
// no reason to migrate if the state is already there
|
|
if one.Equal(two) {
|
|
// Equal isn't identical; it doesn't check lineage.
|
|
sm1, _ := stateOne.(statemgr.PersistentMeta)
|
|
sm2, _ := stateTwo.(statemgr.PersistentMeta)
|
|
if one != nil && two != nil {
|
|
if sm1 == nil || sm2 == nil {
|
|
return nil
|
|
}
|
|
if sm1.StateSnapshotMeta().Lineage == sm2.StateSnapshotMeta().Lineage {
|
|
return nil
|
|
}
|
|
}
|
|
}
|
|
|
|
if m.stateLock {
|
|
lockCtx := context.Background()
|
|
|
|
lockerOne := clistate.NewLocker(lockCtx, m.stateLockTimeout, m.Ui, m.Colorize())
|
|
if err := lockerOne.Lock(stateOne, "migration source state"); err != nil {
|
|
return fmt.Errorf("Error locking source state: %s", err)
|
|
}
|
|
defer lockerOne.Unlock(nil)
|
|
|
|
lockerTwo := clistate.NewLocker(lockCtx, m.stateLockTimeout, m.Ui, m.Colorize())
|
|
if err := lockerTwo.Lock(stateTwo, "migration destination state"); err != nil {
|
|
return fmt.Errorf("Error locking destination state: %s", err)
|
|
}
|
|
defer lockerTwo.Unlock(nil)
|
|
|
|
// We now own a lock, so double check that we have the version
|
|
// corresponding to the lock.
|
|
if err := stateOne.RefreshState(); err != nil {
|
|
return fmt.Errorf(strings.TrimSpace(
|
|
errMigrateSingleLoadDefault), opts.OneType, err)
|
|
}
|
|
if err := stateTwo.RefreshState(); err != nil {
|
|
return fmt.Errorf(strings.TrimSpace(
|
|
errMigrateSingleLoadDefault), opts.OneType, err)
|
|
}
|
|
|
|
one = stateOne.State()
|
|
two = stateTwo.State()
|
|
}
|
|
|
|
var confirmFunc func(state.State, state.State, *backendMigrateOpts) (bool, error)
|
|
switch {
|
|
// No migration necessary
|
|
case one.Empty() && two.Empty():
|
|
return nil
|
|
|
|
// No migration necessary if we're inheriting state.
|
|
case one.Empty() && !two.Empty():
|
|
return nil
|
|
|
|
// We have existing state moving into no state. Ask the user if
|
|
// they'd like to do this.
|
|
case !one.Empty() && two.Empty():
|
|
confirmFunc = m.backendMigrateEmptyConfirm
|
|
|
|
// Both states are non-empty, meaning we need to determine which
|
|
// state should be used and update accordingly.
|
|
case !one.Empty() && !two.Empty():
|
|
confirmFunc = m.backendMigrateNonEmptyConfirm
|
|
}
|
|
|
|
if confirmFunc == nil {
|
|
panic("confirmFunc must not be nil")
|
|
}
|
|
|
|
if !opts.force {
|
|
// Abort if we can't ask for input.
|
|
if !m.input {
|
|
return errors.New("error asking for state migration action: input disabled")
|
|
}
|
|
|
|
// Confirm with the user whether we want to copy state over
|
|
confirm, err := confirmFunc(stateOne, stateTwo, opts)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if !confirm {
|
|
return nil
|
|
}
|
|
}
|
|
|
|
// Confirmed! Write.
|
|
if err := stateTwo.WriteState(one); err != nil {
|
|
return fmt.Errorf(strings.TrimSpace(errBackendStateCopy),
|
|
opts.OneType, opts.TwoType, err)
|
|
}
|
|
if err := stateTwo.PersistState(); err != nil {
|
|
return fmt.Errorf(strings.TrimSpace(errBackendStateCopy),
|
|
opts.OneType, opts.TwoType, err)
|
|
}
|
|
|
|
// And we're done.
|
|
return nil
|
|
}
|
|
|
|
func (m *Meta) backendMigrateEmptyConfirm(one, two state.State, opts *backendMigrateOpts) (bool, error) {
|
|
inputOpts := &terraform.InputOpts{
|
|
Id: "backend-migrate-copy-to-empty",
|
|
Query: "Do you want to copy existing state to the new backend?",
|
|
Description: fmt.Sprintf(
|
|
strings.TrimSpace(inputBackendMigrateEmpty),
|
|
opts.OneType, opts.TwoType),
|
|
}
|
|
|
|
return m.confirm(inputOpts)
|
|
}
|
|
|
|
func (m *Meta) backendMigrateNonEmptyConfirm(
|
|
stateOne, stateTwo state.State, opts *backendMigrateOpts) (bool, error) {
|
|
// We need to grab both states so we can write them to a file
|
|
one := stateOne.State()
|
|
two := stateTwo.State()
|
|
|
|
// Save both to a temporary
|
|
td, err := ioutil.TempDir("", "terraform")
|
|
if err != nil {
|
|
return false, fmt.Errorf("Error creating temporary directory: %s", err)
|
|
}
|
|
defer os.RemoveAll(td)
|
|
|
|
// Helper to write the state
|
|
saveHelper := func(n, path string, s *states.State) error {
|
|
mgr := statemgr.NewFilesystem(path)
|
|
return mgr.WriteState(s)
|
|
}
|
|
|
|
// Write the states
|
|
onePath := filepath.Join(td, fmt.Sprintf("1-%s.tfstate", opts.OneType))
|
|
twoPath := filepath.Join(td, fmt.Sprintf("2-%s.tfstate", opts.TwoType))
|
|
if err := saveHelper(opts.OneType, onePath, one); err != nil {
|
|
return false, fmt.Errorf("Error saving temporary state: %s", err)
|
|
}
|
|
if err := saveHelper(opts.TwoType, twoPath, two); err != nil {
|
|
return false, fmt.Errorf("Error saving temporary state: %s", err)
|
|
}
|
|
|
|
// Ask for confirmation
|
|
inputOpts := &terraform.InputOpts{
|
|
Id: "backend-migrate-to-backend",
|
|
Query: "Do you want to copy existing state to the new backend?",
|
|
Description: fmt.Sprintf(
|
|
strings.TrimSpace(inputBackendMigrateNonEmpty),
|
|
opts.OneType, opts.TwoType, onePath, twoPath),
|
|
}
|
|
|
|
// Confirm with the user that the copy should occur
|
|
return m.confirm(inputOpts)
|
|
}
|
|
|
|
const errMigrateLoadStates = `
|
|
Error inspecting states in the %q backend:
|
|
%s
|
|
|
|
Prior to changing backends, Terraform inspects the source and destination
|
|
states to determine what kind of migration steps need to be taken, if any.
|
|
Terraform failed to load the states. The data in both the source and the
|
|
destination remain unmodified. Please resolve the above error and try again.
|
|
`
|
|
|
|
const errMigrateSingleLoadDefault = `
|
|
Error loading state:
|
|
%[2]s
|
|
|
|
Terraform failed to load the default state from the %[1]q backend.
|
|
State migration cannot occur unless the state can be loaded. Backend
|
|
modification and state migration has been aborted. The state in both the
|
|
source and the destination remain unmodified. Please resolve the
|
|
above error and try again.
|
|
`
|
|
|
|
const errMigrateMulti = `
|
|
Error migrating the workspace %q from the previous %q backend
|
|
to the newly configured %q backend:
|
|
%s
|
|
|
|
Terraform copies workspaces in alphabetical order. Any workspaces
|
|
alphabetically earlier than this one have been copied. Any workspaces
|
|
later than this haven't been modified in the destination. No workspaces
|
|
in the source state have been modified.
|
|
|
|
Please resolve the error above and run the initialization command again.
|
|
This will attempt to copy (with permission) all workspaces again.
|
|
`
|
|
|
|
const errBackendStateCopy = `
|
|
Error copying state from the previous %q backend to the newly configured
|
|
%q backend:
|
|
%s
|
|
|
|
The state in the previous backend remains intact and unmodified. Please resolve
|
|
the error above and try again.
|
|
`
|
|
|
|
const inputBackendMigrateEmpty = `
|
|
Pre-existing state was found while migrating the previous %q backend to the
|
|
newly configured %q backend. No existing state was found in the newly
|
|
configured %[2]q backend. Do you want to copy this state to the new %[2]q
|
|
backend? Enter "yes" to copy and "no" to start with an empty state.
|
|
`
|
|
|
|
const inputBackendMigrateNonEmpty = `
|
|
Pre-existing state was found while migrating the previous %q backend to the
|
|
newly configured %q backend. An existing non-empty state already exists in
|
|
the new backend. The two states have been saved to temporary files that will be
|
|
removed after responding to this query.
|
|
|
|
Previous (type %[1]q): %[3]s
|
|
New (type %[2]q): %[4]s
|
|
|
|
Do you want to overwrite the state in the new backend with the previous state?
|
|
Enter "yes" to copy and "no" to start with the existing state in the newly
|
|
configured %[2]q backend.
|
|
`
|
|
|
|
const inputBackendMigrateMultiToSingle = `
|
|
The existing %[1]q backend supports workspaces and you currently are
|
|
using more than one. The newly configured %[2]q backend doesn't support
|
|
workspaces. If you continue, Terraform will copy your current workspace %[3]q
|
|
to the default workspace in the target backend. Your existing workspaces in the
|
|
source backend won't be modified. If you want to switch workspaces, back them
|
|
up, or cancel altogether, answer "no" and Terraform will abort.
|
|
`
|
|
|
|
const inputBackendMigrateMultiToMulti = `
|
|
Both the existing %[1]q backend and the newly configured %[2]q backend
|
|
support workspaces. When migrating between backends, Terraform will copy
|
|
all workspaces (with the same names). THIS WILL OVERWRITE any conflicting
|
|
states in the destination.
|
|
|
|
Terraform initialization doesn't currently migrate only select workspaces.
|
|
If you want to migrate a select number of workspaces, you must manually
|
|
pull and push those states.
|
|
|
|
If you answer "yes", Terraform will migrate all states. If you answer
|
|
"no", Terraform will abort.
|
|
`
|
|
|
|
const inputBackendNewWorkspaceName = `
|
|
Please provide a new workspace name (e.g. dev, test) that will be used
|
|
to migrate the existing default workspace.
|
|
`
|
|
|
|
const inputBackendSelectWorkspace = `
|
|
This is expected behavior when the selected workspace did not have an
|
|
existing non-empty state. Please enter a number to select a workspace:
|
|
|
|
%s
|
|
`
|