385 lines
12 KiB
Go
385 lines
12 KiB
Go
package command
|
|
|
|
import (
|
|
"fmt"
|
|
"io/ioutil"
|
|
"os"
|
|
"path/filepath"
|
|
"strings"
|
|
|
|
"github.com/hashicorp/terraform/backend"
|
|
clistate "github.com/hashicorp/terraform/command/state"
|
|
"github.com/hashicorp/terraform/state"
|
|
"github.com/hashicorp/terraform/terraform"
|
|
)
|
|
|
|
// 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.States()
|
|
if err == backend.ErrNamedStatesNotSupported {
|
|
oneSingle = true
|
|
err = nil
|
|
}
|
|
if err != nil {
|
|
return fmt.Errorf(strings.TrimSpace(
|
|
errMigrateLoadStates), opts.OneType, err)
|
|
}
|
|
|
|
_, err = opts.Two.States()
|
|
if err == backend.ErrNamedStatesNotSupported {
|
|
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
|
|
|
|
// Determine migration behavior based on whether the source/destionation
|
|
// 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)
|
|
}
|
|
|
|
panic("unhandled")
|
|
}
|
|
|
|
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 single state.
|
|
func (m *Meta) backendMigrateState_S_s(opts *backendMigrateOpts) error {
|
|
currentEnv := m.Env()
|
|
|
|
// 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 environments (named states).\n"+
|
|
"Do you want to copy only your current environment?",
|
|
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
|
|
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.State(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)
|
|
}
|
|
|
|
stateTwo, err := opts.Two.State(opts.twoEnv)
|
|
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)
|
|
}
|
|
|
|
lockInfoOne := state.NewLockInfo()
|
|
lockInfoOne.Operation = "migration"
|
|
lockInfoOne.Info = "source state"
|
|
|
|
lockIDOne, err := clistate.Lock(stateOne, lockInfoOne, m.Ui, m.Colorize())
|
|
if err != nil {
|
|
return fmt.Errorf("Error locking source state: %s", err)
|
|
}
|
|
defer clistate.Unlock(stateOne, lockIDOne, m.Ui, m.Colorize())
|
|
|
|
lockInfoTwo := state.NewLockInfo()
|
|
lockInfoTwo.Operation = "migration"
|
|
lockInfoTwo.Info = "destination state"
|
|
|
|
lockIDTwo, err := clistate.Lock(stateTwo, lockInfoTwo, m.Ui, m.Colorize())
|
|
if err != nil {
|
|
return fmt.Errorf("Error locking destination state: %s", err)
|
|
}
|
|
defer clistate.Unlock(stateTwo, lockIDTwo, m.Ui, m.Colorize())
|
|
|
|
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")
|
|
}
|
|
|
|
// 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: fmt.Sprintf(
|
|
"Do you want to copy state from %q to %q?",
|
|
opts.OneType, opts.TwoType),
|
|
Description: fmt.Sprintf(
|
|
strings.TrimSpace(inputBackendMigrateEmpty),
|
|
opts.OneType, opts.TwoType),
|
|
}
|
|
|
|
// Confirm with the user that the copy should occur
|
|
for {
|
|
v, err := m.UIInput().Input(inputOpts)
|
|
if err != nil {
|
|
return false, fmt.Errorf(
|
|
"Error asking for state copy action: %s", err)
|
|
}
|
|
|
|
switch strings.ToLower(v) {
|
|
case "no":
|
|
return false, nil
|
|
|
|
case "yes":
|
|
return true, nil
|
|
}
|
|
}
|
|
}
|
|
|
|
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 *terraform.State) error {
|
|
f, err := os.Create(path)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
defer f.Close()
|
|
|
|
return terraform.WriteState(s, f)
|
|
}
|
|
|
|
// 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: fmt.Sprintf(
|
|
"Do you want to copy state from %q to %q?",
|
|
opts.OneType, opts.TwoType),
|
|
Description: fmt.Sprintf(
|
|
strings.TrimSpace(inputBackendMigrateNonEmpty),
|
|
opts.OneType, opts.TwoType, onePath, twoPath),
|
|
}
|
|
|
|
// Confirm with the user that the copy should occur
|
|
for {
|
|
v, err := m.UIInput().Input(inputOpts)
|
|
if err != nil {
|
|
return false, fmt.Errorf(
|
|
"Error asking for state copy action: %s", err)
|
|
}
|
|
|
|
switch strings.ToLower(v) {
|
|
case "no":
|
|
return false, nil
|
|
|
|
case "yes":
|
|
return true, nil
|
|
}
|
|
}
|
|
}
|
|
|
|
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
|
|
}
|
|
|
|
const errMigrateLoadStates = `
|
|
Error inspecting state in %q: %s
|
|
|
|
Prior to changing backends, Terraform inspects the source and destionation
|
|
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 from %q: %s
|
|
|
|
Terraform failed to load the default state from %[1]q.
|
|
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 errBackendStateCopy = `
|
|
Error copying state from %q to %q: %s
|
|
|
|
The state in %[1]q remains intact and unmodified. Please resolve the
|
|
error above and try again.
|
|
`
|
|
|
|
const inputBackendMigrateEmpty = `
|
|
Pre-existing state was found in %q while migrating to %q. No existing
|
|
state was found in %[2]q. Do you want to copy the state from %[1]q to
|
|
%[2]q? Enter "yes" to copy and "no" to start with an empty state.
|
|
`
|
|
|
|
const inputBackendMigrateNonEmpty = `
|
|
Pre-existing state was found in %q while migrating to %q. An existing
|
|
non-empty state exists in %[2]q. The two states have been saved to temporary
|
|
files that will be removed after responding to this query.
|
|
|
|
One (%[1]q): %[3]s
|
|
Two (%[2]q): %[4]s
|
|
|
|
Do you want to copy the state from %[1]q to %[2]q? Enter "yes" to copy
|
|
and "no" to start with the existing state in %[2]q.
|
|
`
|
|
|
|
const inputBackendMigrateMultiToSingle = `
|
|
The existing backend %[1]q supports environments and you currently are
|
|
using more than one. The target backend %[2]q doesn't support environments.
|
|
If you continue, Terraform will offer to copy your current environment
|
|
%[3]q to the default environment in the target. Your existing environments
|
|
in the source backend won't be modified. If you want to switch environments,
|
|
back them up, or cancel altogether, answer "no" and Terraform will abort.
|
|
`
|