terraform: missing provider should add missing aliases [GH-2023]

config/config.go

@@ -683,6 +683,10 @@ func (o *Output) mergerMerge(m merger) merger {
 	return &result
 }
 
+func (c *ProviderConfig) GoString() string {
+	return fmt.Sprintf("*%#v", *c)
+}
+
 func (c *ProviderConfig) FullName() string {
 	if c.Alias == "" {
 		return c.Name

terraform/context_test.go

@@ -697,43 +697,6 @@ func TestContext2Plan_preventDestroy_destroyPlan(t *testing.T) {
 	}
 }
 
-func TestContext2Plan_providerAliasMissing(t *testing.T) {
-	m := testModule(t, "apply-provider-alias-missing")
-	p := testProvider("aws")
-	p.ApplyFn = testApplyFn
-	p.DiffFn = testDiffFn
-	state := &State{
-		Modules: []*ModuleState{
-			&ModuleState{
-				Path: rootModulePath,
-				Resources: map[string]*ResourceState{
-					"aws_instance.foo": &ResourceState{
-						Type:     "aws_instance",
-						Provider: "aws.foo",
-						Primary: &InstanceState{
-							ID: "bar",
-							Attributes: map[string]string{
-								"require_new": "abc",
-							},
-						},
-					},
-				},
-			},
-		},
-	}
-	ctx := testContext2(t, &ContextOpts{
-		Module: m,
-		Providers: map[string]ResourceProviderFactory{
-			"aws": testProviderFuncFixed(p),
-		},
-		State: state,
-	})
-
-	if _, err := ctx.Plan(); err == nil {
-		t.Fatal("should err")
-	}
-}
-
 func TestContext2Plan_computed(t *testing.T) {
 	m := testModule(t, "plan-computed")
 	p := testProvider("aws")
@@ -4375,6 +4338,34 @@ func TestContext2Apply_moduleDestroyOrder(t *testing.T) {
 	}
 }
 
+func TestContext2Apply_moduleProviderAlias(t *testing.T) {
+	m := testModule(t, "apply-module-provider-alias")
+	p := testProvider("aws")
+	p.ApplyFn = testApplyFn
+	p.DiffFn = testDiffFn
+	ctx := testContext2(t, &ContextOpts{
+		Module: m,
+		Providers: map[string]ResourceProviderFactory{
+			"aws": testProviderFuncFixed(p),
+		},
+	})
+
+	if _, err := ctx.Plan(); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	state, err := ctx.Apply()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	actual := strings.TrimSpace(state.String())
+	expected := strings.TrimSpace(testTerraformApplyModuleProviderAliasStr)
+	if actual != expected {
+		t.Fatalf("bad: \n%s", actual)
+	}
+}
+
 func TestContext2Apply_moduleVarResourceCount(t *testing.T) {
 	m := testModule(t, "apply-module-var-resource-count")
 	p := testProvider("aws")

terraform/terraform_test.go

@@ -379,6 +379,14 @@ do_instance.foo:
   type = do_instance
 `
 
+const testTerraformApplyModuleProviderAliasStr = `
+<no state>
+module.child:
+  aws_instance.foo:
+    ID = foo
+    provider = aws.eu
+`
+
 const testTerraformApplyOutputOrphanStr = `
 <no state>
 Outputs:

terraform/test-fixtures/apply-module-provider-alias/child/main.tf

@@ -0,0 +1,7 @@
+provider "aws" {
+    alias = "eu"
+}
+
+resource "aws_instance" "foo" {
+    provider = "aws.eu"
+}

terraform/test-fixtures/apply-module-provider-alias/main.tf

@@ -0,0 +1,3 @@
+module "child" {
+    source = "./child"
+}

terraform/test-fixtures/transform-provider-missing/main.tf

@@ -0,0 +1,3 @@
+provider "aws" {}
+resource "aws_instance" "web" {}
+resource "foo_instance" "web" {}

terraform/transform_provider.go

@@ -2,6 +2,7 @@ package terraform
 
 import (
 	"fmt"
+	"strings"
 
 	"github.com/hashicorp/go-multierror"
 	"github.com/hashicorp/terraform/config"
@@ -146,15 +147,44 @@ type MissingProviderTransformer struct {
 }
 
 func (t *MissingProviderTransformer) Transform(g *Graph) error {
+	// Create a set of our supported providers
+	supported := make(map[string]struct{}, len(t.Providers))
+	for _, v := range t.Providers {
+		supported[v] = struct{}{}
+	}
+
+	// Get the map of providers we already have in our graph
 	m := providerVertexMap(g)
-	for _, p := range t.Providers {
-		if _, ok := m[p]; ok {
-			// This provider already exists as a configured node
+
+	// Go through all the provider consumers and make sure we add
+	// that provider if it is missing.
+	for _, v := range g.Vertices() {
+		pv, ok := v.(GraphNodeProviderConsumer)
+		if !ok {
 			continue
 		}
 
-		// Add our own missing provider node to the graph
-		g.Add(&graphNodeMissingProvider{ProviderNameValue: p})
+		for _, p := range pv.ProvidedBy() {
+			if _, ok := m[p]; ok {
+				// This provider already exists as a configure node
+				break
+			}
+
+			// If the provider has an alias in it, we just want the type
+			ptype := p
+			if idx := strings.IndexRune(p, '.'); idx != -1 {
+				ptype = p[:idx]
+			}
+
+			if _, ok := supported[ptype]; !ok {
+				// If we don't support the provider type, skip it.
+				// Validation later will catch this as an error.
+				continue
+			}
+
+			// Add our own missing provider node to the graph
+			m[p] = g.Add(&graphNodeMissingProvider{ProviderNameValue: p})
+		}
 	}
 
 	return nil

terraform/transform_provider_test.go

@@ -63,7 +63,7 @@ func TestCloseProviderTransformer(t *testing.T) {
 }
 
 func TestMissingProviderTransformer(t *testing.T) {
-	mod := testModule(t, "transform-provider-basic")
+	mod := testModule(t, "transform-provider-missing")
 
 	g := Graph{Path: RootModulePath}
 	{
@@ -74,7 +74,7 @@ func TestMissingProviderTransformer(t *testing.T) {
 	}
 
 	{
-		transform := &MissingProviderTransformer{Providers: []string{"foo"}}
+		transform := &MissingProviderTransformer{Providers: []string{"foo", "bar"}}
 		if err := transform.Transform(&g); err != nil {
 			t.Fatalf("err: %s", err)
 		}
@@ -275,10 +275,13 @@ provider.aws (close)
 
 const testTransformMissingProviderBasicStr = `
 aws_instance.web
+foo_instance.web
 provider.aws
 provider.aws (close)
   aws_instance.web
 provider.foo
+provider.foo (close)
+  foo_instance.web
 `
 
 const testTransformPruneProviderBasicStr = `