terraform: begin NodePlannableResource

terraform/context.go

@@ -487,7 +487,7 @@ func (c *Context) Plan() (*Plan, error) {
 	c.diffLock.Unlock()
 
 	// Used throughout below
-	X_newApply := experiment.Enabled(experiment.X_newDestroy)
+	X_newApply := experiment.Enabled(experiment.X_newApply)
 	X_newDestroy := experiment.Enabled(experiment.X_newDestroy)
 	newGraphEnabled := (c.destroy && X_newDestroy) || (!c.destroy && X_newApply)
 
@@ -515,8 +515,11 @@ func (c *Context) Plan() (*Plan, error) {
 			Targets: c.targets,
 		}).Build(RootModulePath)
 	} else {
-		// TODO: new plan graph when its ready
-		newGraph = nil
+		newGraph, err = (&PlanGraphBuilder{
+			Module:    c.module,
+			State:     c.state,
+			Providers: c.components.ResourceProviders(),
+		}).Build(RootModulePath)
 	}
 	if err != nil && !newGraphEnabled {
 		// If we had an error graphing but we're not using this graph, just
@@ -554,6 +557,9 @@ func (c *Context) Plan() (*Plan, error) {
 		shadow = nil
 	}
 
+	// TODO: remove when we're ready
+	shadow = nil
+
 	// Do the walk
 	walker, err := c.walk(real, shadow, operation)
 	if err != nil {
@@ -574,7 +580,7 @@ func (c *Context) Plan() (*Plan, error) {
 
 	// We don't do the reverification during the new destroy plan because
 	// it will use a different apply process.
-	if !(c.destroy && X_newDestroy) {
+	if !newGraphEnabled {
 		// Now that we have a diff, we can build the exact graph that Apply will use
 		// and catch any possible cycles during the Plan phase.
 		if _, err := c.Graph(&ContextGraphOpts{Validate: true}); err != nil {

terraform/context_plan_test.go

@@ -11,7 +11,7 @@ import (
 	"testing"
 )
 
-func TestContext2Plan(t *testing.T) {
+func TestContext2Plan_basic(t *testing.T) {
 	m := testModule(t, "plan-good")
 	p := testProvider("aws")
 	p.DiffFn = testDiffFn

terraform/graph_builder_plan.go

@@ -50,7 +50,7 @@ func (b *PlanGraphBuilder) Steps() []GraphTransformer {
 	}
 
 	concreteResource := func(a *NodeAbstractResource) dag.Vertex {
-		return &NodeApplyableResource{
+		return &NodePlannableResource{
 			NodeAbstractResource: a,
 		}
 	}

terraform/node_resource_plan.go

@@ -0,0 +1,207 @@
+package terraform
+
+import (
+	"fmt"
+
+	"github.com/hashicorp/terraform/config"
+)
+
+// NodePlannableResource represents a resource that is "plannable":
+// it is ready to be planned in order to create a diff.
+type NodePlannableResource struct {
+	*NodeAbstractResource
+}
+
+// GraphNodeEvalable
+func (n *NodePlannableResource) EvalTree() EvalNode {
+	addr := n.NodeAbstractResource.Addr
+
+	// stateId is the ID to put into the state
+	stateId := addr.stateId()
+	if addr.Index > -1 {
+		stateId = fmt.Sprintf("%s.%d", stateId, addr.Index)
+	}
+
+	// Build the instance info. More of this will be populated during eval
+	info := &InstanceInfo{
+		Id:   stateId,
+		Type: addr.Type,
+	}
+
+	// Build the resource for eval
+	resource := &Resource{
+		Name:       addr.Name,
+		Type:       addr.Type,
+		CountIndex: addr.Index,
+	}
+	if resource.CountIndex < 0 {
+		resource.CountIndex = 0
+	}
+
+	// Determine the dependencies for the state. We use some older
+	// code for this that we've used for a long time.
+	var stateDeps []string
+	{
+		oldN := &graphNodeExpandedResource{Resource: n.Config}
+		stateDeps = oldN.StateDependencies()
+	}
+
+	// Eval info is different depending on what kind of resource this is
+	switch n.Config.Mode {
+	case config.ManagedResourceMode:
+		return n.evalTreeManagedResource(
+			stateId, info, resource, stateDeps,
+		)
+	case config.DataResourceMode:
+		return n.evalTreeDataResource(
+			stateId, info, resource, stateDeps)
+	default:
+		panic(fmt.Errorf("unsupported resource mode %s", n.Config.Mode))
+	}
+}
+
+func (n *NodePlannableResource) evalTreeDataResource(
+	stateId string, info *InstanceInfo,
+	resource *Resource, stateDeps []string) EvalNode {
+	var provider ResourceProvider
+	var config *ResourceConfig
+	var diff *InstanceDiff
+	var state *InstanceState
+
+	return &EvalSequence{
+		Nodes: []EvalNode{
+			// Get the saved diff for apply
+			&EvalReadDiff{
+				Name: stateId,
+				Diff: &diff,
+			},
+
+			// Stop here if we don't actually have a diff
+			&EvalIf{
+				If: func(ctx EvalContext) (bool, error) {
+					if diff == nil {
+						return true, EvalEarlyExitError{}
+					}
+
+					if diff.GetAttributesLen() == 0 {
+						return true, EvalEarlyExitError{}
+					}
+
+					return true, nil
+				},
+				Then: EvalNoop{},
+			},
+
+			// We need to re-interpolate the config here, rather than
+			// just using the diff's values directly, because we've
+			// potentially learned more variable values during the
+			// apply pass that weren't known when the diff was produced.
+			&EvalInterpolate{
+				Config:   n.Config.RawConfig.Copy(),
+				Resource: resource,
+				Output:   &config,
+			},
+
+			&EvalGetProvider{
+				Name:   n.ProvidedBy()[0],
+				Output: &provider,
+			},
+
+			// Make a new diff with our newly-interpolated config.
+			&EvalReadDataDiff{
+				Info:     info,
+				Config:   &config,
+				Previous: &diff,
+				Provider: &provider,
+				Output:   &diff,
+			},
+
+			&EvalReadDataApply{
+				Info:     info,
+				Diff:     &diff,
+				Provider: &provider,
+				Output:   &state,
+			},
+
+			&EvalWriteState{
+				Name:         stateId,
+				ResourceType: n.Config.Type,
+				Provider:     n.Config.Provider,
+				Dependencies: stateDeps,
+				State:        &state,
+			},
+
+			// Clear the diff now that we've applied it, so
+			// later nodes won't see a diff that's now a no-op.
+			&EvalWriteDiff{
+				Name: stateId,
+				Diff: nil,
+			},
+
+			&EvalUpdateStateHook{},
+		},
+	}
+}
+
+func (n *NodePlannableResource) evalTreeManagedResource(
+	stateId string, info *InstanceInfo,
+	resource *Resource, stateDeps []string) EvalNode {
+	// Declare a bunch of variables that are used for state during
+	// evaluation. Most of this are written to by-address below.
+	var provider ResourceProvider
+	var diff *InstanceDiff
+	var state *InstanceState
+	var resourceConfig *ResourceConfig
+
+	return &EvalSequence{
+		Nodes: []EvalNode{
+			&EvalInterpolate{
+				Config:   n.Config.RawConfig.Copy(),
+				Resource: resource,
+				Output:   &resourceConfig,
+			},
+			&EvalGetProvider{
+				Name:   n.ProvidedBy()[0],
+				Output: &provider,
+			},
+			// Re-run validation to catch any errors we missed, e.g. type
+			// mismatches on computed values.
+			&EvalValidateResource{
+				Provider:       &provider,
+				Config:         &resourceConfig,
+				ResourceName:   n.Config.Name,
+				ResourceType:   n.Config.Type,
+				ResourceMode:   n.Config.Mode,
+				IgnoreWarnings: true,
+			},
+			&EvalReadState{
+				Name:   stateId,
+				Output: &state,
+			},
+			&EvalDiff{
+				Info:        info,
+				Config:      &resourceConfig,
+				Resource:    n.Config,
+				Provider:    &provider,
+				State:       &state,
+				OutputDiff:  &diff,
+				OutputState: &state,
+			},
+			&EvalCheckPreventDestroy{
+				Resource: n.Config,
+				Diff:     &diff,
+			},
+			&EvalWriteState{
+				Name:         stateId,
+				ResourceType: n.Config.Type,
+				Provider:     n.Config.Provider,
+				Dependencies: stateDeps,
+				State:        &state,
+			},
+			&EvalWriteDiff{
+				Name: stateId,
+				Diff: &diff,
+			},
+		},
+	}
+}