terraform: basic provider validation!

terraform/context_test.go

@@ -80,7 +80,7 @@ func TestContext2Validate_orphans(t *testing.T) {
 		t.Fatalf("bad: %#v", w)
 	}
 	if len(e) > 0 {
-		t.Fatalf("bad: %#v", e)
+		t.Fatalf("bad: %s", e)
 	}
 }
 

terraform/eval_sequence.go

@@ -0,0 +1,33 @@
+package terraform
+
+// EvalSequence is an EvalNode that evaluates in sequence.
+type EvalSequence struct {
+	Nodes []EvalNode
+}
+
+func (n *EvalSequence) Args() ([]EvalNode, []EvalType) {
+	types := make([]EvalType, len(n.Nodes))
+	for i, n := range n.Nodes {
+		types[i] = n.Type()
+	}
+
+	return n.Nodes, types
+}
+
+func (n *EvalSequence) Eval(
+	ctx EvalContext, args []interface{}) (interface{}, error) {
+	// TODO: test
+	if len(args) == 0 {
+		return nil, nil
+	}
+
+	return args[len(args)-1], nil
+}
+
+func (n *EvalSequence) Type() EvalType {
+	if len(n.Nodes) == 0 {
+		return EvalTypeNull
+	}
+
+	return n.Nodes[len(n.Nodes)-1].Type()
+}

terraform/eval_validate.go

@@ -15,17 +15,48 @@ func (e *EvalValidateError) Error() string {
 	return ""
 }
 
+// EvalValidateProvider is an EvalNode implementation that validates
+// the configuration of a resource.
+type EvalValidateProvider struct {
+	Provider EvalNode
+	Config   EvalNode
+}
+
+func (n *EvalValidateProvider) Args() ([]EvalNode, []EvalType) {
+	return []EvalNode{n.Provider, n.Config},
+		[]EvalType{EvalTypeResourceProvider, EvalTypeConfig}
+}
+
+func (n *EvalValidateProvider) Eval(
+	ctx EvalContext, args []interface{}) (interface{}, error) {
+	provider := args[0].(ResourceProvider)
+	config := args[1].(*ResourceConfig)
+	warns, errs := provider.Validate(config)
+	if len(warns) == 0 && len(errs) == 0 {
+		return nil, nil
+	}
+
+	return nil, &EvalValidateError{
+		Warnings: warns,
+		Errors:   errs,
+	}
+}
+
+func (n *EvalValidateProvider) Type() EvalType {
+	return EvalTypeNull
+}
+
 // EvalValidateResource is an EvalNode implementation that validates
 // the configuration of a resource.
 type EvalValidateResource struct {
 	Provider     EvalNode
-	Config       *config.RawConfig
+	Config       EvalNode
 	ProviderType string
 }
 
 func (n *EvalValidateResource) Args() ([]EvalNode, []EvalType) {
-	return []EvalNode{n.Provider},
-		[]EvalType{EvalTypeResourceProvider}
+	return []EvalNode{n.Provider, n.Config},
+		[]EvalType{EvalTypeResourceProvider, EvalTypeConfig}
 }
 
 func (n *EvalValidateResource) Eval(

terraform/graph_config_node.go

@@ -75,9 +75,18 @@ func (n *GraphNodeConfigProvider) DependentOn() []string {
 
 // GraphNodeEvalable impl.
 func (n *GraphNodeConfigProvider) EvalTree() EvalNode {
-	return &EvalConfigProvider{
-		Provider: &EvalGetProvider{Name: n.Provider.Name},
-		Config:   &EvalInterpolate{Config: n.Provider.RawConfig},
+	return &EvalSequence{
+		Nodes: []EvalNode{
+			&EvalInitProvider{Name: n.Provider.Name},
+			&EvalValidateProvider{
+				Provider: &EvalGetProvider{Name: n.Provider.Name},
+				Config:   &EvalInterpolate{Config: n.Provider.RawConfig},
+			},
+			&EvalConfigProvider{
+				Provider: &EvalGetProvider{Name: n.Provider.Name},
+				Config:   &EvalInterpolate{Config: n.Provider.RawConfig},
+			},
+		},
 	}
 }
 
@@ -121,11 +130,14 @@ func (n *GraphNodeConfigResource) Name() string {
 
 // GraphNodeEvalable impl.
 func (n *GraphNodeConfigResource) EvalTree() EvalNode {
-	return &EvalValidateResource{
-		Provider: &EvalGetProvider{Name: n.ProvidedBy()},
-
-		Config:       n.Resource.RawConfig,
-		ProviderType: n.ProvidedBy(),
+	return &EvalSequence{
+		Nodes: []EvalNode{
+			&EvalValidateResource{
+				Provider:     &EvalGetProvider{Name: n.ProvidedBy()},
+				Config:       n.Resource.RawConfig,
+				ProviderType: n.ProvidedBy(),
+			},
+		},
 	}
 }