terraform/backend/local/backend_local.go

255 lines
8.5 KiB
Go

package local
import (
"context"
"fmt"
"log"
"github.com/hashicorp/errwrap"
"github.com/hashicorp/terraform/backend"
"github.com/hashicorp/terraform/command/clistate"
"github.com/hashicorp/terraform/configs/configload"
"github.com/hashicorp/terraform/plans/planfile"
"github.com/hashicorp/terraform/states/statemgr"
"github.com/hashicorp/terraform/terraform"
"github.com/hashicorp/terraform/tfdiags"
"github.com/zclconf/go-cty/cty"
)
// backend.Local implementation.
func (b *Local) Context(op *backend.Operation) (*terraform.Context, statemgr.Full, tfdiags.Diagnostics) {
// Make sure the type is invalid. We use this as a way to know not
// to ask for input/validate.
op.Type = backend.OperationTypeInvalid
if op.LockState {
op.StateLocker = clistate.NewLocker(context.Background(), op.StateLockTimeout, b.CLI, b.Colorize())
} else {
op.StateLocker = clistate.NewNoopLocker()
}
ctx, _, stateMgr, diags := b.context(op)
return ctx, stateMgr, diags
}
func (b *Local) context(op *backend.Operation) (*terraform.Context, *configload.Snapshot, statemgr.Full, tfdiags.Diagnostics) {
var diags tfdiags.Diagnostics
// Get the latest state.
log.Printf("[TRACE] backend/local: requesting state manager for workspace %q", op.Workspace)
s, err := b.StateMgr(op.Workspace)
if err != nil {
diags = diags.Append(errwrap.Wrapf("Error loading state: {{err}}", err))
return nil, nil, nil, diags
}
log.Printf("[TRACE] backend/local: requesting state lock for workspace %q", op.Workspace)
if err := op.StateLocker.Lock(s, op.Type.String()); err != nil {
diags = diags.Append(errwrap.Wrapf("Error locking state: {{err}}", err))
return nil, nil, nil, diags
}
log.Printf("[TRACE] backend/local: reading remote state for workspace %q", op.Workspace)
if err := s.RefreshState(); err != nil {
diags = diags.Append(errwrap.Wrapf("Error loading state: {{err}}", err))
return nil, nil, nil, diags
}
// Initialize our context options
var opts terraform.ContextOpts
if v := b.ContextOpts; v != nil {
opts = *v
}
// Copy set options from the operation
opts.Destroy = op.Destroy
opts.Targets = op.Targets
opts.UIInput = op.UIIn
// Load the latest state. If we enter contextFromPlanFile below then the
// state snapshot in the plan file must match this, or else it'll return
// error diagnostics.
log.Printf("[TRACE] backend/local: retrieving local state snapshot for workspace %q", op.Workspace)
opts.State = s.State()
var tfCtx *terraform.Context
var ctxDiags tfdiags.Diagnostics
var configSnap *configload.Snapshot
if op.PlanFile != nil {
var stateMeta *statemgr.SnapshotMeta
// If the statemgr implements our optional PersistentMeta interface then we'll
// additionally verify that the state snapshot in the plan file has
// consistent metadata, as an additional safety check.
if sm, ok := s.(statemgr.PersistentMeta); ok {
m := sm.StateSnapshotMeta()
stateMeta = &m
}
log.Printf("[TRACE] backend/local: building context from plan file")
tfCtx, configSnap, ctxDiags = b.contextFromPlanFile(op.PlanFile, opts, stateMeta)
// Write sources into the cache of the main loader so that they are
// available if we need to generate diagnostic message snippets.
op.ConfigLoader.ImportSourcesFromSnapshot(configSnap)
} else {
log.Printf("[TRACE] backend/local: building context for current working directory")
tfCtx, configSnap, ctxDiags = b.contextDirect(op, opts)
}
diags = diags.Append(ctxDiags)
if diags.HasErrors() {
return nil, nil, nil, diags
}
log.Printf("[TRACE] backend/local: finished building terraform.Context")
// If we have an operation, then we automatically do the input/validate
// here since every option requires this.
if op.Type != backend.OperationTypeInvalid {
// If input asking is enabled, then do that
if op.PlanFile == nil && b.OpInput {
mode := terraform.InputModeProvider
mode |= terraform.InputModeVar
mode |= terraform.InputModeVarUnset
log.Printf("[TRACE] backend/local: requesting interactive input, if necessary")
inputDiags := tfCtx.Input(mode)
diags = diags.Append(inputDiags)
if inputDiags.HasErrors() {
return nil, nil, nil, diags
}
}
// If validation is enabled, validate
if b.OpValidation {
log.Printf("[TRACE] backend/local: running validation operation")
validateDiags := tfCtx.Validate()
diags = diags.Append(validateDiags)
}
}
return tfCtx, configSnap, s, diags
}
func (b *Local) contextDirect(op *backend.Operation, opts terraform.ContextOpts) (*terraform.Context, *configload.Snapshot, tfdiags.Diagnostics) {
var diags tfdiags.Diagnostics
// Load the configuration using the caller-provided configuration loader.
config, configSnap, configDiags := op.ConfigLoader.LoadConfigWithSnapshot(op.ConfigDir)
diags = diags.Append(configDiags)
if configDiags.HasErrors() {
return nil, nil, diags
}
opts.Config = config
variables, varDiags := backend.ParseVariableValues(op.Variables, config.Module.Variables)
diags = diags.Append(varDiags)
if diags.HasErrors() {
return nil, nil, diags
}
if op.Variables != nil {
opts.Variables = variables
}
tfCtx, ctxDiags := terraform.NewContext(&opts)
diags = diags.Append(ctxDiags)
return tfCtx, configSnap, diags
}
func (b *Local) contextFromPlanFile(pf *planfile.Reader, opts terraform.ContextOpts, currentStateMeta *statemgr.SnapshotMeta) (*terraform.Context, *configload.Snapshot, tfdiags.Diagnostics) {
var diags tfdiags.Diagnostics
const errSummary = "Invalid plan file"
// A plan file has a snapshot of configuration embedded inside it, which
// is used instead of whatever configuration might be already present
// in the filesystem.
snap, err := pf.ReadConfigSnapshot()
if err != nil {
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
errSummary,
fmt.Sprintf("Failed to read configuration snapshot from plan file: %s.", err),
))
return nil, snap, diags
}
loader := configload.NewLoaderFromSnapshot(snap)
config, configDiags := loader.LoadConfig(snap.Modules[""].Dir)
diags = diags.Append(configDiags)
if configDiags.HasErrors() {
return nil, snap, diags
}
opts.Config = config
// A plan file also contains a snapshot of the prior state the changes
// are intended to apply to.
priorStateFile, err := pf.ReadStateFile()
if err != nil {
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
errSummary,
fmt.Sprintf("Failed to read prior state snapshot from plan file: %s.", err),
))
return nil, snap, diags
}
if currentStateMeta != nil {
// If the caller sets this, we require that the stored prior state
// has the same metadata, which is an extra safety check that nothing
// has changed since the plan was created. (All of the "real-world"
// state manager implementstions support this, but simpler test backends
// may not.)
if currentStateMeta.Lineage != "" && priorStateFile.Lineage != "" {
if priorStateFile.Serial != currentStateMeta.Serial || priorStateFile.Lineage != currentStateMeta.Lineage {
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
"Saved plan is stale",
"The given plan file can no longer be applied because the state was changed by another operation after the plan was created.",
))
}
}
}
// The caller already wrote the "current state" here, but we're overriding
// it here with the prior state. These two should actually be identical in
// normal use, particularly if we validated the state meta above, but
// we do this here anyway to ensure consistent behavior.
opts.State = priorStateFile.State
plan, err := pf.ReadPlan()
if err != nil {
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
errSummary,
fmt.Sprintf("Failed to read plan from plan file: %s.", err),
))
return nil, snap, diags
}
variables := terraform.InputValues{}
for name, dyVal := range plan.VariableValues {
val, err := dyVal.Decode(cty.DynamicPseudoType)
if err != nil {
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
errSummary,
fmt.Sprintf("Invalid value for variable %q recorded in plan file: %s.", name, err),
))
continue
}
variables[name] = &terraform.InputValue{
Value: val,
SourceType: terraform.ValueFromPlan,
}
}
opts.Variables = variables
opts.Changes = plan.Changes
opts.Targets = plan.TargetAddrs
opts.ProviderSHA256s = plan.ProviderSHA256s
tfCtx, ctxDiags := terraform.NewContext(&opts)
diags = diags.Append(ctxDiags)
return tfCtx, snap, diags
}
const validateWarnHeader = `
There are warnings related to your configuration. If no errors occurred,
Terraform will continue despite these warnings. It is a good idea to resolve
these warnings in the near future.
Warnings:
`