terraform: Refresh supports new data sources

terraform/context.go

@@ -233,6 +233,15 @@ func (c *Context) Graph(typ GraphType, opts *ContextGraphOpts) (*Graph, error) {
 			Validate: opts.Validate,
 		}).Build(RootModulePath)
 
+	case GraphTypeRefresh:
+		return (&RefreshGraphBuilder{
+			Module:    c.module,
+			State:     c.state,
+			Providers: c.components.ResourceProviders(),
+			Targets:   c.targets,
+			Validate:  opts.Validate,
+		}).Build(RootModulePath)
+
 	case GraphTypeLegacy:
 		return c.graphBuilder(opts).Build(RootModulePath)
 	}
@@ -569,8 +578,15 @@ func (c *Context) Refresh() (*State, error) {
 	// Copy our own state
 	c.state = c.state.DeepCopy()
 
-	// Build the graph
-	graph, err := c.Graph(GraphTypeLegacy, nil)
+	// Used throughout below
+	X_legacyGraph := experiment.Enabled(experiment.X_legacyGraph)
+
+	// Build the graph.
+	graphType := GraphTypeLegacy
+	if !X_legacyGraph {
+		graphType = GraphTypeRefresh
+	}
+	graph, err := c.Graph(graphType, nil)
 	if err != nil {
 		return nil, err
 	}

terraform/context_graph_type.go

@@ -10,6 +10,7 @@ type GraphType byte
 const (
 	GraphTypeInvalid GraphType = 0
 	GraphTypeLegacy  GraphType = iota
+	GraphTypeRefresh
 	GraphTypePlan
 	GraphTypePlanDestroy
 	GraphTypeApply
@@ -22,5 +23,6 @@ var GraphTypeMap = map[string]GraphType{
 	"apply":        GraphTypeApply,
 	"plan":         GraphTypePlan,
 	"plan-destroy": GraphTypePlanDestroy,
+	"refresh":      GraphTypeRefresh,
 	"legacy":       GraphTypeLegacy,
 }

terraform/context_refresh_test.go

@@ -520,7 +520,7 @@ func TestContext2Refresh_outputPartial(t *testing.T) {
 	}
 }
 
-func TestContext2Refresh_state(t *testing.T) {
+func TestContext2Refresh_stateBasic(t *testing.T) {
 	p := testProvider("aws")
 	m := testModule(t, "refresh-basic")
 	state := &State{
@@ -529,6 +529,7 @@ func TestContext2Refresh_state(t *testing.T) {
 				Path: rootModulePath,
 				Resources: map[string]*ResourceState{
 					"aws_instance.web": &ResourceState{
+						Type: "aws_instance",
 						Primary: &InstanceState{
 							ID: "bar",
 						},
@@ -737,6 +738,21 @@ func TestContext2Refresh_unknownProvider(t *testing.T) {
 	ctx := testContext2(t, &ContextOpts{
 		Module:    m,
 		Providers: map[string]ResourceProviderFactory{},
+		State: &State{
+			Modules: []*ModuleState{
+				&ModuleState{
+					Path: rootModulePath,
+					Resources: map[string]*ResourceState{
+						"aws_instance.web": &ResourceState{
+							Type: "aws_instance",
+							Primary: &InstanceState{
+								ID: "foo",
+							},
+						},
+					},
+				},
+			},
+		},
 	})
 
 	if _, err := ctx.Refresh(); err == nil {

terraform/graph_builder_refresh.go

@@ -0,0 +1,121 @@
+package terraform
+
+import (
+	"github.com/hashicorp/terraform/config"
+	"github.com/hashicorp/terraform/config/module"
+	"github.com/hashicorp/terraform/dag"
+)
+
+// RefreshGraphBuilder implements GraphBuilder and is responsible for building
+// a graph for refreshing (updating the Terraform state).
+//
+// The primary difference between this graph and others:
+//
+//   * Based on the state since it represents the only resources that
+//     need to be refreshed.
+//
+//   * Ignores lifecycle options since no lifecycle events occur here. This
+//     simplifies the graph significantly since complex transforms such as
+//     create-before-destroy can be completely ignored.
+//
+type RefreshGraphBuilder struct {
+	// Module is the root module for the graph to build.
+	Module *module.Tree
+
+	// State is the current state
+	State *State
+
+	// Providers is the list of providers supported.
+	Providers []string
+
+	// Targets are resources to target
+	Targets []string
+
+	// DisableReduce, if true, will not reduce the graph. Great for testing.
+	DisableReduce bool
+
+	// Validate will do structural validation of the graph.
+	Validate bool
+}
+
+// See GraphBuilder
+func (b *RefreshGraphBuilder) Build(path []string) (*Graph, error) {
+	return (&BasicGraphBuilder{
+		Steps:    b.Steps(),
+		Validate: b.Validate,
+		Name:     "RefreshGraphBuilder",
+	}).Build(path)
+}
+
+// See GraphBuilder
+func (b *RefreshGraphBuilder) Steps() []GraphTransformer {
+	// Custom factory for creating providers.
+	concreteProvider := func(a *NodeAbstractProvider) dag.Vertex {
+		return &NodeApplyableProvider{
+			NodeAbstractProvider: a,
+		}
+	}
+
+	concreteResource := func(a *NodeAbstractResource) dag.Vertex {
+		return &NodeRefreshableResource{
+			NodeAbstractResource: a,
+		}
+	}
+
+	steps := []GraphTransformer{
+		// Creates all the resources represented in the state
+		&StateTransformer{
+			Concrete: concreteResource,
+			State:    b.State,
+		},
+
+		// Creates all the data resources that aren't in the state
+		&ConfigTransformer{
+			Concrete:   concreteResource,
+			Module:     b.Module,
+			Unique:     true,
+			ModeFilter: true,
+			Mode:       config.DataResourceMode,
+		},
+
+		// Attach the state
+		&AttachStateTransformer{State: b.State},
+
+		// Attach the configuration to any resources
+		&AttachResourceConfigTransformer{Module: b.Module},
+
+		// Add root variables
+		&RootVariableTransformer{Module: b.Module},
+
+		// Create all the providers
+		&MissingProviderTransformer{Providers: b.Providers, Concrete: concreteProvider},
+		&ProviderTransformer{},
+		&DisableProviderTransformer{},
+		&ParentProviderTransformer{},
+		&AttachProviderConfigTransformer{Module: b.Module},
+
+		// Add the outputs
+		&OutputTransformer{Module: b.Module},
+
+		// Add module variables
+		&ModuleVariableTransformer{Module: b.Module},
+
+		// Connect so that the references are ready for targeting. We'll
+		// have to connect again later for providers and so on.
+		&ReferenceTransformer{},
+
+		// Target
+		&TargetsTransformer{Targets: b.Targets},
+
+		// Single root
+		&RootTransformer{},
+	}
+
+	if !b.DisableReduce {
+		// Perform the transitive reduction to make our graph a bit
+		// more sane if possible (it usually is possible).
+		steps = append(steps, &TransitiveReductionTransformer{})
+	}
+
+	return steps
+}

terraform/graphtype_string.go

@@ -4,9 +4,9 @@ package terraform
 
 import "fmt"
 
-const _GraphType_name = "GraphTypeInvalidGraphTypeLegacyGraphTypePlanGraphTypePlanDestroyGraphTypeApply"
+const _GraphType_name = "GraphTypeInvalidGraphTypeLegacyGraphTypeRefreshGraphTypePlanGraphTypePlanDestroyGraphTypeApply"
 
-var _GraphType_index = [...]uint8{0, 16, 31, 44, 64, 78}
+var _GraphType_index = [...]uint8{0, 16, 31, 47, 60, 80, 94}
 
 func (i GraphType) String() string {
 	if i >= GraphType(len(_GraphType_index)-1) {

terraform/node_resource_refresh.go

@@ -0,0 +1,222 @@
+package terraform
+
+import (
+	"fmt"
+
+	"github.com/hashicorp/terraform/config"
+)
+
+// NodeRefreshableResource represents a resource that is "applyable":
+// it is ready to be applied and is represented by a diff.
+type NodeRefreshableResource struct {
+	*NodeAbstractResource
+}
+
+// GraphNodeDestroyer
+func (n *NodeRefreshableResource) DestroyAddr() *ResourceAddress {
+	return n.Addr
+}
+
+// GraphNodeEvalable
+func (n *NodeRefreshableResource) EvalTree() EvalNode {
+	// Eval info is different depending on what kind of resource this is
+	switch mode := n.Addr.Mode; mode {
+	case config.ManagedResourceMode:
+		return n.evalTreeManagedResource()
+	case config.DataResourceMode:
+		return n.evalTreeDataResource()
+	default:
+		panic(fmt.Errorf("unsupported resource mode %s", mode))
+	}
+}
+
+func (n *NodeRefreshableResource) evalTreeManagedResource() EvalNode {
+	addr := n.NodeAbstractResource.Addr
+
+	// stateId is the ID to put into the state
+	stateId := addr.stateId()
+
+	// Build the instance info. More of this will be populated during eval
+	info := &InstanceInfo{
+		Id:   stateId,
+		Type: addr.Type,
+	}
+
+	// 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 state *InstanceState
+
+	// This happened during initial development. All known cases were
+	// fixed and tested but as a sanity check let's assert here.
+	if n.ResourceState == nil {
+		err := fmt.Errorf(
+			"No resource state attached for addr: %s\n\n"+
+				"This is a bug. Please report this to Terraform with your configuration\n"+
+				"and state attached. Please be careful to scrub any sensitive information.",
+			addr)
+		return &EvalReturnError{Error: &err}
+	}
+
+	return &EvalSequence{
+		Nodes: []EvalNode{
+			&EvalGetProvider{
+				Name:   n.ProvidedBy()[0],
+				Output: &provider,
+			},
+			&EvalReadState{
+				Name:   stateId,
+				Output: &state,
+			},
+			&EvalRefresh{
+				Info:     info,
+				Provider: &provider,
+				State:    &state,
+				Output:   &state,
+			},
+			&EvalWriteState{
+				Name:         stateId,
+				ResourceType: n.ResourceState.Type,
+				Provider:     n.ResourceState.Provider,
+				Dependencies: n.ResourceState.Dependencies,
+				State:        &state,
+			},
+		},
+	}
+}
+
+func (n *NodeRefreshableResource) evalTreeDataResource() EvalNode {
+	addr := n.NodeAbstractResource.Addr
+
+	// stateId is the ID to put into the state
+	stateId := addr.stateId()
+
+	// Build the instance info. More of this will be populated during eval
+	info := &InstanceInfo{
+		Id:   stateId,
+		Type: addr.Type,
+	}
+
+	// Get the state if we have it, if not we build it
+	rs := n.ResourceState
+	if rs == nil {
+		rs = &ResourceState{}
+	}
+
+	// If the config isn't empty we update the state
+	if n.Config != nil {
+		// 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,
+				Index:    addr.Index,
+			}
+			stateDeps = oldN.StateDependencies()
+		}
+
+		rs = &ResourceState{
+			Type:         n.Config.Type,
+			Provider:     n.Config.Provider,
+			Dependencies: stateDeps,
+		}
+	}
+
+	// Build the resource for eval
+	resource := &Resource{
+		Name:       addr.Name,
+		Type:       addr.Type,
+		CountIndex: addr.Index,
+	}
+	if resource.CountIndex < 0 {
+		resource.CountIndex = 0
+	}
+
+	// Declare a bunch of variables that are used for state during
+	// evaluation. Most of this are written to by-address below.
+	var config *ResourceConfig
+	var diff *InstanceDiff
+	var provider ResourceProvider
+	var state *InstanceState
+
+	return &EvalSequence{
+		Nodes: []EvalNode{
+			// Always destroy the existing state first, since we must
+			// make sure that values from a previous read will not
+			// get interpolated if we end up needing to defer our
+			// loading until apply time.
+			&EvalWriteState{
+				Name:         stateId,
+				ResourceType: rs.Type,
+				Provider:     rs.Provider,
+				Dependencies: rs.Dependencies,
+				State:        &state, // state is nil here
+			},
+
+			&EvalInterpolate{
+				Config:   n.Config.RawConfig.Copy(),
+				Resource: resource,
+				Output:   &config,
+			},
+
+			// The rest of this pass can proceed only if there are no
+			// computed values in our config.
+			// (If there are, we'll deal with this during the plan and
+			// apply phases.)
+			&EvalIf{
+				If: func(ctx EvalContext) (bool, error) {
+					if config.ComputedKeys != nil && len(config.ComputedKeys) > 0 {
+						return true, EvalEarlyExitError{}
+					}
+
+					// If the config explicitly has a depends_on for this
+					// data source, assume the intention is to prevent
+					// refreshing ahead of that dependency.
+					if len(n.Config.DependsOn) > 0 {
+						return true, EvalEarlyExitError{}
+					}
+
+					return true, nil
+				},
+
+				Then: EvalNoop{},
+			},
+
+			// The remainder of this pass is the same as running
+			// a "plan" pass immediately followed by an "apply" pass,
+			// populating the state early so it'll be available to
+			// provider configurations that need this data during
+			// refresh/plan.
+			&EvalGetProvider{
+				Name:   n.ProvidedBy()[0],
+				Output: &provider,
+			},
+
+			&EvalReadDataDiff{
+				Info:        info,
+				Config:      &config,
+				Provider:    &provider,
+				Output:      &diff,
+				OutputState: &state,
+			},
+
+			&EvalReadDataApply{
+				Info:     info,
+				Diff:     &diff,
+				Provider: &provider,
+				Output:   &state,
+			},
+
+			&EvalWriteState{
+				Name:         stateId,
+				ResourceType: rs.Type,
+				Provider:     rs.Provider,
+				Dependencies: rs.Dependencies,
+				State:        &state,
+			},
+
+			&EvalUpdateStateHook{},
+		},
+	}
+}

terraform/transform_attach_state.go

@@ -45,8 +45,10 @@ func (t *AttachStateTransformer) Transform(g *Graph) error {
 		}
 
 		// Attach the first resource state we get
+		log.Printf("SEARCH: %s", addr)
 		found := false
 		for _, result := range results {
+			log.Printf("WTF: %s %#v", addr, result)
 			if rs, ok := result.Value.(*ResourceState); ok {
 				log.Printf(
 					"[DEBUG] Attaching resource state to %q: %s",