terraform: InstanceInfo.uniqueId

This adds a new function to get a unique identifier scoped to the graph
walk in order to identify operations against the same instance. This is
used by the shadow to namespace provider function calls.

terraform/resource.go

@@ -62,6 +62,12 @@ type InstanceInfo struct {
 
 	// Type is the resource type of this instance
 	Type string
+
+	// uniqueExtra is an internal field that can be populated to supply
+	// extra metadata that is used to identify a unique instance in
+	// the graph walk. This will be appended to HumanID when uniqueId
+	// is called.
+	uniqueExtra string
 }
 
 // HumanId is a unique Id that is human-friendly and useful for UI elements.
@@ -76,6 +82,15 @@ func (i *InstanceInfo) HumanId() string {
 		i.Id)
 }
 
+func (i *InstanceInfo) uniqueId() string {
+	prefix := i.HumanId()
+	if v := i.uniqueExtra; v != "" {
+		prefix += " " + v
+	}
+
+	return prefix
+}
+
 // ResourceConfig holds the configuration given for a resource. This is
 // done instead of a raw `map[string]interface{}` type so that rich
 // methods can be added to it to make dealing with it easier.

terraform/shadow_resource_provider.go

@@ -155,7 +155,7 @@ func (p *shadowResourceProviderReal) Apply(
 	diffCopy := diff.DeepCopy()
 
 	result, err := p.ResourceProvider.Apply(info, state, diff)
-	p.Shared.Apply.SetValue(info.HumanId(), &shadowResourceProviderApply{
+	p.Shared.Apply.SetValue(info.uniqueId(), &shadowResourceProviderApply{
 		State:     stateCopy,
 		Diff:      diffCopy,
 		Result:    result.DeepCopy(),
@@ -173,7 +173,7 @@ func (p *shadowResourceProviderReal) Diff(
 	stateCopy := state.DeepCopy()
 
 	result, err := p.ResourceProvider.Diff(info, state, desired)
-	p.Shared.Diff.SetValue(info.HumanId(), &shadowResourceProviderDiff{
+	p.Shared.Diff.SetValue(info.uniqueId(), &shadowResourceProviderDiff{
 		State:     stateCopy,
 		Desired:   desired,
 		Result:    result.DeepCopy(),
@@ -190,7 +190,7 @@ func (p *shadowResourceProviderReal) Refresh(
 	stateCopy := state.DeepCopy()
 
 	result, err := p.ResourceProvider.Refresh(info, state)
-	p.Shared.Refresh.SetValue(info.HumanId(), &shadowResourceProviderRefresh{
+	p.Shared.Refresh.SetValue(info.uniqueId(), &shadowResourceProviderRefresh{
 		State:     stateCopy,
 		Result:    result.DeepCopy(),
 		ResultErr: err,
@@ -420,7 +420,7 @@ func (p *shadowResourceProviderShadow) Apply(
 	state *InstanceState,
 	diff *InstanceDiff) (*InstanceState, error) {
 	// Unique key
-	key := info.HumanId()
+	key := info.uniqueId()
 	raw := p.Shared.Apply.Value(key)
 	if raw == nil {
 		p.ErrorLock.Lock()
@@ -459,7 +459,7 @@ func (p *shadowResourceProviderShadow) Diff(
 	state *InstanceState,
 	desired *ResourceConfig) (*InstanceDiff, error) {
 	// Unique key
-	key := info.HumanId()
+	key := info.uniqueId()
 	raw := p.Shared.Diff.Value(key)
 	if raw == nil {
 		p.ErrorLock.Lock()
@@ -502,7 +502,7 @@ func (p *shadowResourceProviderShadow) Refresh(
 	info *InstanceInfo,
 	state *InstanceState) (*InstanceState, error) {
 	// Unique key
-	key := info.HumanId()
+	key := info.uniqueId()
 	raw := p.Shared.Refresh.Value(key)
 	if raw == nil {
 		p.ErrorLock.Lock()

terraform/transform_resource.go

@@ -862,7 +862,7 @@ func (n *graphNodeExpandedResourceDestroy) ConfigType() GraphNodeConfigType {
 // GraphNodeEvalable impl.
 func (n *graphNodeExpandedResourceDestroy) EvalTree() EvalNode {
 	info := n.instanceInfo()
-	info.Id += " (destroy)"
+	info.uniqueExtra = "destroy"
 
 	var diffApply *InstanceDiff
 	var provider ResourceProvider