terraform/terraform/node_resource_apply_instanc...

429 lines
15 KiB
Go

package terraform
import (
"fmt"
"log"
"github.com/hashicorp/terraform/addrs"
"github.com/hashicorp/terraform/configs"
"github.com/hashicorp/terraform/plans"
"github.com/hashicorp/terraform/plans/objchange"
"github.com/hashicorp/terraform/states"
"github.com/hashicorp/terraform/tfdiags"
)
// NodeApplyableResourceInstance represents a resource instance that is
// "applyable": it is ready to be applied and is represented by a diff.
//
// This node is for a specific instance of a resource. It will usually be
// accompanied in the graph by a NodeApplyableResource representing its
// containing resource, and should depend on that node to ensure that the
// state is properly prepared to receive changes to instances.
type NodeApplyableResourceInstance struct {
*NodeAbstractResourceInstance
graphNodeDeposer // implementation of GraphNodeDeposerConfig
// If this node is forced to be CreateBeforeDestroy, we need to record that
// in the state to.
ForceCreateBeforeDestroy bool
}
var (
_ GraphNodeConfigResource = (*NodeApplyableResourceInstance)(nil)
_ GraphNodeResourceInstance = (*NodeApplyableResourceInstance)(nil)
_ GraphNodeCreator = (*NodeApplyableResourceInstance)(nil)
_ GraphNodeReferencer = (*NodeApplyableResourceInstance)(nil)
_ GraphNodeDeposer = (*NodeApplyableResourceInstance)(nil)
_ GraphNodeExecutable = (*NodeApplyableResourceInstance)(nil)
_ GraphNodeAttachDependencies = (*NodeApplyableResourceInstance)(nil)
)
// CreateBeforeDestroy returns this node's CreateBeforeDestroy status.
func (n *NodeApplyableResourceInstance) CreateBeforeDestroy() bool {
if n.ForceCreateBeforeDestroy {
return n.ForceCreateBeforeDestroy
}
if n.Config != nil && n.Config.Managed != nil {
return n.Config.Managed.CreateBeforeDestroy
}
return false
}
func (n *NodeApplyableResourceInstance) ModifyCreateBeforeDestroy(v bool) error {
n.ForceCreateBeforeDestroy = v
return nil
}
// GraphNodeCreator
func (n *NodeApplyableResourceInstance) CreateAddr() *addrs.AbsResourceInstance {
addr := n.ResourceInstanceAddr()
return &addr
}
// GraphNodeReferencer, overriding NodeAbstractResourceInstance
func (n *NodeApplyableResourceInstance) References() []*addrs.Reference {
// Start with the usual resource instance implementation
ret := n.NodeAbstractResourceInstance.References()
// Applying a resource must also depend on the destruction of any of its
// dependencies, since this may for example affect the outcome of
// evaluating an entire list of resources with "count" set (by reducing
// the count).
//
// However, we can't do this in create_before_destroy mode because that
// would create a dependency cycle. We make a compromise here of requiring
// changes to be updated across two applies in this case, since the first
// plan will use the old values.
if !n.CreateBeforeDestroy() {
for _, ref := range ret {
switch tr := ref.Subject.(type) {
case addrs.ResourceInstance:
newRef := *ref // shallow copy so we can mutate
newRef.Subject = tr.Phase(addrs.ResourceInstancePhaseDestroy)
newRef.Remaining = nil // can't access attributes of something being destroyed
ret = append(ret, &newRef)
case addrs.Resource:
newRef := *ref // shallow copy so we can mutate
newRef.Subject = tr.Phase(addrs.ResourceInstancePhaseDestroy)
newRef.Remaining = nil // can't access attributes of something being destroyed
ret = append(ret, &newRef)
}
}
}
return ret
}
// GraphNodeAttachDependencies
func (n *NodeApplyableResourceInstance) AttachDependencies(deps []addrs.ConfigResource) {
n.Dependencies = deps
}
// GraphNodeExecutable
func (n *NodeApplyableResourceInstance) Execute(ctx EvalContext, op walkOperation) (diags tfdiags.Diagnostics) {
addr := n.ResourceInstanceAddr()
if n.Config == nil {
// This should not be possible, but we've got here in at least one
// case as discussed in the following issue:
// https://github.com/hashicorp/terraform/issues/21258
// To avoid an outright crash here, we'll instead return an explicit
// error.
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
"Resource node has no configuration attached",
fmt.Sprintf(
"The graph node for %s has no configuration attached to it. This suggests a bug in Terraform's apply graph builder; please report it!",
addr,
),
))
return diags
}
// Eval info is different depending on what kind of resource this is
switch n.Config.Mode {
case addrs.ManagedResourceMode:
return n.managedResourceExecute(ctx)
case addrs.DataResourceMode:
return n.dataResourceExecute(ctx)
default:
panic(fmt.Errorf("unsupported resource mode %s", n.Config.Mode))
}
}
func (n *NodeApplyableResourceInstance) dataResourceExecute(ctx EvalContext) (diags tfdiags.Diagnostics) {
_, providerSchema, err := getProvider(ctx, n.ResolvedProvider)
diags = diags.Append(err)
if diags.HasErrors() {
return diags
}
change, err := n.readDiff(ctx, providerSchema)
diags = diags.Append(err)
if diags.HasErrors() {
return diags
}
// Stop early if we don't actually have a diff
if change == nil {
return diags
}
// In this particular call to applyDataSource we include our planned
// change, which signals that we expect this read to complete fully
// with no unknown values; it'll produce an error if not.
state, applyDiags := n.applyDataSource(ctx, change)
diags = diags.Append(applyDiags)
if diags.HasErrors() {
return diags
}
// We don't write dependencies for datasources
diags = diags.Append(n.writeResourceInstanceState(ctx, state, nil, workingState))
if diags.HasErrors() {
return diags
}
diags = diags.Append(n.writeChange(ctx, nil, ""))
diags = diags.Append(updateStateHook(ctx))
return diags
}
func (n *NodeApplyableResourceInstance) managedResourceExecute(ctx EvalContext) (diags tfdiags.Diagnostics) {
// Declare a bunch of variables that are used for state during
// evaluation. Most of this are written to by-address below.
var state *states.ResourceInstanceObject
var createBeforeDestroyEnabled bool
var deposedKey states.DeposedKey
addr := n.ResourceInstanceAddr().Resource
_, providerSchema, err := getProvider(ctx, n.ResolvedProvider)
diags = diags.Append(err)
if diags.HasErrors() {
return diags
}
// Get the saved diff for apply
diffApply, err := n.readDiff(ctx, providerSchema)
diags = diags.Append(err)
if diags.HasErrors() {
return diags
}
// We don't want to do any destroys
// (these are handled by NodeDestroyResourceInstance instead)
if diffApply == nil || diffApply.Action == plans.Delete {
return diags
}
destroy := (diffApply.Action == plans.Delete || diffApply.Action.IsReplace())
// Get the stored action for CBD if we have a plan already
createBeforeDestroyEnabled = diffApply.Change.Action == plans.CreateThenDelete
if destroy && n.CreateBeforeDestroy() {
createBeforeDestroyEnabled = true
}
if createBeforeDestroyEnabled {
state := ctx.State()
if n.PreallocatedDeposedKey == states.NotDeposed {
deposedKey = state.DeposeResourceInstanceObject(n.Addr)
} else {
deposedKey = n.PreallocatedDeposedKey
state.DeposeResourceInstanceObjectForceKey(n.Addr, deposedKey)
}
log.Printf("[TRACE] managedResourceExecute: prior object for %s now deposed with key %s", n.Addr, deposedKey)
}
state, err = n.readResourceInstanceState(ctx, n.ResourceInstanceAddr())
diags = diags.Append(err)
if diags.HasErrors() {
return diags
}
// Get the saved diff
diff, err := n.readDiff(ctx, providerSchema)
diags = diags.Append(err)
if diags.HasErrors() {
return diags
}
// Make a new diff, in case we've learned new values in the state
// during apply which we can now incorporate.
diffApply, _, planDiags := n.plan(ctx, diff, state, false)
diags = diags.Append(planDiags)
if diags.HasErrors() {
return diags
}
// Compare the diffs
diags = diags.Append(n.checkPlannedChange(ctx, diff, diffApply, providerSchema))
if diags.HasErrors() {
return diags
}
state, err = n.readResourceInstanceState(ctx, n.ResourceInstanceAddr())
diags = diags.Append(err)
if diags.HasErrors() {
return diags
}
diffApply = reducePlan(addr, diffApply, false)
// reducePlan may have simplified our planned change
// into a NoOp if it only requires destroying, since destroying
// is handled by NodeDestroyResourceInstance.
if diffApply == nil || diffApply.Action == plans.NoOp {
return diags
}
diags = diags.Append(n.preApplyHook(ctx, diffApply))
if diags.HasErrors() {
return diags
}
state, applyDiags := n.apply(ctx, state, diffApply, n.Config, n.CreateBeforeDestroy())
diags = diags.Append(applyDiags)
// We clear the change out here so that future nodes don't see a change
// that is already complete.
err = n.writeChange(ctx, nil, "")
if err != nil {
return diags.Append(err)
}
state = maybeTainted(addr.Absolute(ctx.Path()), state, diffApply, diags.Err())
err = n.writeResourceInstanceState(ctx, state, n.Dependencies, workingState)
if err != nil {
return diags.Append(err)
}
// Run Provisioners
createNew := (diffApply.Action == plans.Create || diffApply.Action.IsReplace())
applyProvisionersDiags := n.evalApplyProvisioners(ctx, state, createNew, configs.ProvisionerWhenCreate)
// the provisioner errors count as port of the apply error, so we can bundle the diags
diags = diags.Append(applyProvisionersDiags)
state = maybeTainted(addr.Absolute(ctx.Path()), state, diffApply, diags.Err())
err = n.writeResourceInstanceState(ctx, state, n.Dependencies, workingState)
if err != nil {
return diags.Append(err)
}
if createBeforeDestroyEnabled && diags.HasErrors() {
if deposedKey == states.NotDeposed {
// This should never happen, and so it always indicates a bug.
// We should evaluate this node only if we've previously deposed
// an object as part of the same operation.
if diffApply != nil {
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
"Attempt to restore non-existent deposed object",
fmt.Sprintf(
"Terraform has encountered a bug where it would need to restore a deposed object for %s without knowing a deposed object key for that object. This occurred during a %s action. This is a bug in Terraform; please report it!",
addr, diffApply.Action,
),
))
} else {
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
"Attempt to restore non-existent deposed object",
fmt.Sprintf(
"Terraform has encountered a bug where it would need to restore a deposed object for %s without knowing a deposed object key for that object. This is a bug in Terraform; please report it!",
addr,
),
))
}
} else {
restored := ctx.State().MaybeRestoreResourceInstanceDeposed(addr.Absolute(ctx.Path()), deposedKey)
if restored {
log.Printf("[TRACE] managedResourceExecute: %s deposed object %s was restored as the current object", addr, deposedKey)
} else {
log.Printf("[TRACE] managedResourceExecute: %s deposed object %s remains deposed", addr, deposedKey)
}
}
}
diags = diags.Append(n.postApplyHook(ctx, state, diags.Err()))
diags = diags.Append(updateStateHook(ctx))
return diags
}
// checkPlannedChange produces errors if the _actual_ expected value is not
// compatible with what was recorded in the plan.
//
// Errors here are most often indicative of a bug in the provider, so our error
// messages will report with that in mind. It's also possible that there's a bug
// in Terraform's Core's own "proposed new value" code in EvalDiff.
func (n *NodeApplyableResourceInstance) checkPlannedChange(ctx EvalContext, plannedChange, actualChange *plans.ResourceInstanceChange, providerSchema *ProviderSchema) tfdiags.Diagnostics {
var diags tfdiags.Diagnostics
addr := n.ResourceInstanceAddr().Resource
schema, _ := providerSchema.SchemaForResourceAddr(addr.ContainingResource())
if schema == nil {
// Should be caught during validation, so we don't bother with a pretty error here
diags = diags.Append(fmt.Errorf("provider does not support %q", addr.Resource.Type))
return diags
}
absAddr := addr.Absolute(ctx.Path())
log.Printf("[TRACE] checkPlannedChange: Verifying that actual change (action %s) matches planned change (action %s)", actualChange.Action, plannedChange.Action)
if plannedChange.Action != actualChange.Action {
switch {
case plannedChange.Action == plans.Update && actualChange.Action == plans.NoOp:
// It's okay for an update to become a NoOp once we've filled in
// all of the unknown values, since the final values might actually
// match what was there before after all.
log.Printf("[DEBUG] After incorporating new values learned so far during apply, %s change has become NoOp", absAddr)
case (plannedChange.Action == plans.CreateThenDelete && actualChange.Action == plans.DeleteThenCreate) ||
(plannedChange.Action == plans.DeleteThenCreate && actualChange.Action == plans.CreateThenDelete):
// If the order of replacement changed, then that is a bug in terraform
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
"Terraform produced inconsistent final plan",
fmt.Sprintf(
"When expanding the plan for %s to include new values learned so far during apply, the planned action changed from %s to %s.\n\nThis is a bug in Terraform and should be reported.",
absAddr, plannedChange.Action, actualChange.Action,
),
))
default:
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
"Provider produced inconsistent final plan",
fmt.Sprintf(
"When expanding the plan for %s to include new values learned so far during apply, provider %q changed the planned action from %s to %s.\n\nThis is a bug in the provider, which should be reported in the provider's own issue tracker.",
absAddr, n.ResolvedProvider.Provider.String(),
plannedChange.Action, actualChange.Action,
),
))
}
}
errs := objchange.AssertObjectCompatible(schema, plannedChange.After, actualChange.After)
for _, err := range errs {
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
"Provider produced inconsistent final plan",
fmt.Sprintf(
"When expanding the plan for %s to include new values learned so far during apply, provider %q produced an invalid new value for %s.\n\nThis is a bug in the provider, which should be reported in the provider's own issue tracker.",
absAddr, n.ResolvedProvider.Provider.String(), tfdiags.FormatError(err),
),
))
}
return diags
}
// maybeTainted takes the resource addr, new value, planned change, and possible
// error from an apply operation and return a new instance object marked as
// tainted if it appears that a create operation has failed.
func maybeTainted(addr addrs.AbsResourceInstance, state *states.ResourceInstanceObject, change *plans.ResourceInstanceChange, err error) *states.ResourceInstanceObject {
if state == nil || change == nil || err == nil {
return state
}
if state.Status == states.ObjectTainted {
log.Printf("[TRACE] maybeTainted: %s was already tainted, so nothing to do", addr)
return state
}
if change.Action == plans.Create {
// If there are errors during a _create_ then the object is
// in an undefined state, and so we'll mark it as tainted so
// we can try again on the next run.
//
// We don't do this for other change actions because errors
// during updates will often not change the remote object at all.
// If there _were_ changes prior to the error, it's the provider's
// responsibility to record the effect of those changes in the
// object value it returned.
log.Printf("[TRACE] maybeTainted: %s encountered an error during creation, so it is now marked as tainted", addr)
return state.AsTainted()
}
return state
}