terraform: transform for adding orphan resources + tests

terraform/test-fixtures/transform-orphan-count-empty/main.tf

@@ -0,0 +1 @@
+# Purposefully empty

terraform/test-fixtures/transform-orphan-count/main.tf

@@ -0,0 +1 @@
+resource "aws_instance" "foo" { count = 3 }

terraform/transform_orphan_resource.go

@@ -0,0 +1,74 @@
+package terraform
+
+import (
+	"github.com/hashicorp/terraform/config"
+	"github.com/hashicorp/terraform/config/module"
+	"github.com/hashicorp/terraform/dag"
+)
+
+// OrphanResourceTransformer is a GraphTransformer that adds resource
+// orphans to the graph. A resource orphan is a resource that is
+// represented in the state but not in the configuration.
+//
+// This only adds orphans that have no representation at all in the
+// configuration.
+type OrphanResourceTransformer struct {
+	Concrete ConcreteResourceNodeFunc
+
+	// State is the global state. We require the global state to
+	// properly find module orphans at our path.
+	State *State
+
+	// Module is the root module. We'll look up the proper configuration
+	// using the graph path.
+	Module *module.Tree
+}
+
+func (t *OrphanResourceTransformer) Transform(g *Graph) error {
+	if t.State == nil {
+		// If the entire state is nil, there can't be any orphans
+		return nil
+	}
+
+	// Go through the modules and for each module transform in order
+	// to add the orphan.
+	for _, ms := range t.State.Modules {
+		if err := t.transform(g, ms); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (t *OrphanResourceTransformer) transform(g *Graph, ms *ModuleState) error {
+	// Get the configuration for this path. The configuration might be
+	// nil if the module was removed from the configuration. This is okay,
+	// this just means that every resource is an orphan.
+	var c *config.Config
+	if m := t.Module.Child(ms.Path[1:]); m != nil {
+		c = m.Config()
+	}
+
+	// Go through the orphans and add them all to the state
+	for _, key := range ms.Orphans(c) {
+		// Build the abstract resource
+		addr, err := parseResourceAddressInternal(key)
+		if err != nil {
+			return err
+		}
+		addr.Path = ms.Path[1:]
+
+		// Build the abstract node and the concrete one
+		abstract := &NodeAbstractResource{Addr: addr}
+		var node dag.Vertex = abstract
+		if f := t.Concrete; f != nil {
+			node = f(abstract)
+		}
+
+		// Add it to the graph
+		g.Add(node)
+	}
+
+	return nil
+}

terraform/transform_orphan_resource_test.go

@@ -0,0 +1,246 @@
+package terraform
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+
+	"github.com/hashicorp/terraform/dag"
+)
+
+func TestOrphanResourceTransformer(t *testing.T) {
+	mod := testModule(t, "transform-orphan-basic")
+	state := &State{
+		Modules: []*ModuleState{
+			&ModuleState{
+				Path: RootModulePath,
+				Resources: map[string]*ResourceState{
+					"aws_instance.web": &ResourceState{
+						Type: "aws_instance",
+						Primary: &InstanceState{
+							ID: "foo",
+						},
+					},
+
+					// The orphan
+					"aws_instance.db": &ResourceState{
+						Type: "aws_instance",
+						Primary: &InstanceState{
+							ID: "foo",
+						},
+					},
+				},
+			},
+		},
+	}
+
+	g := Graph{Path: RootModulePath}
+	{
+		tf := &ConfigTransformer{Module: mod}
+		if err := tf.Transform(&g); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+	}
+
+	{
+		tf := &OrphanResourceTransformer{
+			Concrete: testOrphanResourceConcreteFunc,
+			State:    state, Module: mod,
+		}
+		if err := tf.Transform(&g); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+	}
+
+	actual := strings.TrimSpace(g.String())
+	expected := strings.TrimSpace(testTransformOrphanResourceBasicStr)
+	if actual != expected {
+		t.Fatalf("bad:\n\n%s", actual)
+	}
+}
+
+func TestOrphanResourceTransformer_countGood(t *testing.T) {
+	mod := testModule(t, "transform-orphan-count")
+	state := &State{
+		Modules: []*ModuleState{
+			&ModuleState{
+				Path: RootModulePath,
+				Resources: map[string]*ResourceState{
+					"aws_instance.foo.0": &ResourceState{
+						Type: "aws_instance",
+						Primary: &InstanceState{
+							ID: "foo",
+						},
+					},
+
+					"aws_instance.foo.1": &ResourceState{
+						Type: "aws_instance",
+						Primary: &InstanceState{
+							ID: "foo",
+						},
+					},
+				},
+			},
+		},
+	}
+
+	g := Graph{Path: RootModulePath}
+	{
+		tf := &ConfigTransformer{Module: mod}
+		if err := tf.Transform(&g); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+	}
+
+	{
+		tf := &OrphanResourceTransformer{
+			Concrete: testOrphanResourceConcreteFunc,
+			State:    state, Module: mod,
+		}
+		if err := tf.Transform(&g); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+	}
+
+	actual := strings.TrimSpace(g.String())
+	expected := strings.TrimSpace(testTransformOrphanResourceCountStr)
+	if actual != expected {
+		t.Fatalf("bad:\n\n%s", actual)
+	}
+}
+
+func TestOrphanResourceTransformer_countBad(t *testing.T) {
+	mod := testModule(t, "transform-orphan-count-empty")
+	state := &State{
+		Modules: []*ModuleState{
+			&ModuleState{
+				Path: RootModulePath,
+				Resources: map[string]*ResourceState{
+					"aws_instance.foo.0": &ResourceState{
+						Type: "aws_instance",
+						Primary: &InstanceState{
+							ID: "foo",
+						},
+					},
+
+					"aws_instance.foo.1": &ResourceState{
+						Type: "aws_instance",
+						Primary: &InstanceState{
+							ID: "foo",
+						},
+					},
+				},
+			},
+		},
+	}
+
+	g := Graph{Path: RootModulePath}
+	{
+		tf := &ConfigTransformer{Module: mod}
+		if err := tf.Transform(&g); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+	}
+
+	{
+		tf := &OrphanResourceTransformer{
+			Concrete: testOrphanResourceConcreteFunc,
+			State:    state, Module: mod,
+		}
+		if err := tf.Transform(&g); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+	}
+
+	actual := strings.TrimSpace(g.String())
+	expected := strings.TrimSpace(testTransformOrphanResourceCountBadStr)
+	if actual != expected {
+		t.Fatalf("bad:\n\n%s", actual)
+	}
+}
+
+func TestOrphanResourceTransformer_modules(t *testing.T) {
+	mod := testModule(t, "transform-orphan-modules")
+	state := &State{
+		Modules: []*ModuleState{
+			&ModuleState{
+				Path: RootModulePath,
+				Resources: map[string]*ResourceState{
+					"aws_instance.foo": &ResourceState{
+						Type: "aws_instance",
+						Primary: &InstanceState{
+							ID: "foo",
+						},
+					},
+				},
+			},
+
+			&ModuleState{
+				Path: []string{"root", "child"},
+				Resources: map[string]*ResourceState{
+					"aws_instance.web": &ResourceState{
+						Type: "aws_instance",
+						Primary: &InstanceState{
+							ID: "foo",
+						},
+					},
+				},
+			},
+		},
+	}
+
+	g := Graph{Path: RootModulePath}
+	{
+		tf := &ConfigTransformer{Module: mod}
+		if err := tf.Transform(&g); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+	}
+
+	{
+		tf := &OrphanResourceTransformer{
+			Concrete: testOrphanResourceConcreteFunc,
+			State:    state, Module: mod,
+		}
+		if err := tf.Transform(&g); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+	}
+
+	actual := strings.TrimSpace(g.String())
+	expected := strings.TrimSpace(testTransformOrphanResourceModulesStr)
+	if actual != expected {
+		t.Fatalf("bad:\n\n%s", actual)
+	}
+}
+
+const testTransformOrphanResourceBasicStr = `
+aws_instance.db (orphan)
+aws_instance.web
+`
+
+const testTransformOrphanResourceCountStr = `
+aws_instance.foo
+`
+
+const testTransformOrphanResourceCountBadStr = `
+aws_instance.foo[0] (orphan)
+aws_instance.foo[1] (orphan)
+`
+
+const testTransformOrphanResourceModulesStr = `
+aws_instance.foo
+module.child.aws_instance.web (orphan)
+`
+
+func testOrphanResourceConcreteFunc(a *NodeAbstractResource) dag.Vertex {
+	return &testOrphanResourceConcrete{a}
+}
+
+type testOrphanResourceConcrete struct {
+	*NodeAbstractResource
+}
+
+func (n *testOrphanResourceConcrete) Name() string {
+	return fmt.Sprintf("%s (orphan)", n.NodeAbstractResource.Name())
+}