adding exclude flag to plan and apply to exclude specified resource from map

command/apply.go

@@ -351,7 +351,8 @@ Options:
 
   -target=resource       Resource to target. Operation will be limited to this
                          resource and its dependencies. This flag can be used
-                         multiple times.
+                         multiple times. Prefixing the resource with ! will
+                         exclude the resource.
 
   -var 'foo=bar'         Set a variable in the Terraform configuration. This
                          flag can be set multiple times.

command/plan.go

@@ -171,7 +171,8 @@ Options:
 
   -target=resource    Resource to target. Operation will be limited to this
                       resource and its dependencies. This flag can be used
-                      multiple times.
+                      multiple times. Prefixing the resource with ! will
+											exclude the resource.
 
   -var 'foo=bar'      Set a variable in the Terraform configuration. This
                       flag can be set multiple times.

terraform/transform_targets.go

@@ -41,27 +41,36 @@ type TargetsTransformer struct {
 	// that already have the targets parsed
 	ParsedTargets []ResourceAddress
 
+	// List of parsed excludes, provided by callers like ResourceCountTransform
+	// that already have the targets parsed
+	ParsedExcludes []ResourceAddress
+
 	// Set to true when we're in a `terraform destroy` or a
 	// `terraform plan -destroy`
 	Destroy bool
 }
 
 func (t *TargetsTransformer) Transform(g *Graph) error {
 	if len(t.Targets) > 0 && len(t.ParsedTargets) == 0 {
-		addrs, err := t.parseTargetAddresses()
+		targeted, excluded, err := t.parseTargetAddresses()
 		if err != nil {
 			return err
 		}
-
-		t.ParsedTargets = addrs
+		t.ParsedTargets = targeted
+		t.ParsedExcludes = excluded
 	}
 
-	if len(t.ParsedTargets) > 0 {
+	if len(t.ParsedTargets) > 0 || len(t.ParsedExcludes) > 0 {
 		targetedNodes, err := t.selectTargetedNodes(g, t.ParsedTargets)
 		if err != nil {
 			return err
 		}
 
+		excludedNodes, err := t.selectTargetedNodes(g, t.ParsedExcludes)
+		if err != nil {
+			return err
+		}
+
 		for _, v := range g.Vertices() {
 			removable := false
 			if _, ok := v.(GraphNodeResource); ok {
@@ -70,27 +79,40 @@ func (t *TargetsTransformer) Transform(g *Graph) error {
 			if vr, ok := v.(RemovableIfNotTargeted); ok {
 				removable = vr.RemoveIfNotTargeted()
 			}
-			if removable && !targetedNodes.Include(v) {
-				log.Printf("[DEBUG] Removing %q, filtered by targeting.", dag.VertexName(v))
-				g.Remove(v)
+			if removable {
+				if len(t.ParsedTargets) > 0 && !targetedNodes.Include(v) {
+					log.Printf("[DEBUG] Removing %q, filtered by targeting.", dag.VertexName(v))
+					g.Remove(v)
+				} else if len(t.ParsedExcludes) > 0 && excludedNodes.Include(v) {
+					log.Printf("[DEBUG] Removing %s, filtered by excluding.", dag.VertexName(v))
+					g.Remove(v)
+				}
 			}
 		}
 	}
 
 	return nil
 }
 
-func (t *TargetsTransformer) parseTargetAddresses() ([]ResourceAddress, error) {
-	addrs := make([]ResourceAddress, len(t.Targets))
-	for i, target := range t.Targets {
+func (t *TargetsTransformer) parseTargetAddresses() ([]ResourceAddress, []ResourceAddress, error) {
+	var targeted, excluded []ResourceAddress
+	for _, target := range t.Targets {
+		exclude := string(target[0]) == "!"
+		if exclude {
+			target = target[1:]
+			log.Printf("[DEBUG] Excluding %s", target)
+		}
 		ta, err := ParseResourceAddress(target)
 		if err != nil {
-			return nil, err
+			return nil, nil, err
+		}
+		if exclude {
+			excluded = append(excluded, *ta)
+		} else {
+			targeted = append(targeted, *ta)
 		}
-		addrs[i] = *ta
 	}
-
-	return addrs, nil
+	return targeted, excluded, nil
 }
 
 // Returns the list of targeted nodes. A targeted node is either addressed

terraform/transform_targets_test.go

@@ -160,3 +160,101 @@ aws_instance.metoo
 		t.Fatalf("bad:\n\nexpected:\n%s\n\ngot:\n%s\n", expected, actual)
 	}
 }
+
+func TestTargetsTransformer_exclude(t *testing.T) {
+	mod := testModule(t, "transform-targets-basic")
+
+	g := Graph{Path: RootModulePath}
+	{
+		tf := &ConfigTransformer{Module: mod}
+		if err := tf.Transform(&g); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+	}
+
+	{
+		transform := &TargetsTransformer{Targets: []string{"!aws_instance.me"}}
+		if err := transform.Transform(&g); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+	}
+
+	actual := strings.TrimSpace(g.String())
+	expected := strings.TrimSpace(`
+aws_instance.notme
+aws_instance.notmeeither
+aws_subnet.me
+aws_subnet.notme
+aws_vpc.me
+aws_vpc.notme
+	`)
+	if actual != expected {
+		t.Fatalf("bad:\n\nexpected:\n%s\n\ngot:\n%s\n", expected, actual)
+	}
+}
+
+func TestTargetsTransformer_exclude_destroy(t *testing.T) {
+	mod := testModule(t, "transform-targets-destroy")
+
+	g := Graph{Path: RootModulePath}
+	{
+		tf := &ConfigTransformer{Module: mod}
+		if err := tf.Transform(&g); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+	}
+
+	{
+		transform := &TargetsTransformer{
+			Targets: []string{"!aws_instance.me"},
+			Destroy: true,
+		}
+		if err := transform.Transform(&g); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+	}
+
+	actual := strings.TrimSpace(g.String())
+	expected := strings.TrimSpace(`
+aws_elb.me
+aws_instance.metoo
+aws_instance.notme
+aws_subnet.notme
+aws_vpc.notme
+	`)
+	if actual != expected {
+		t.Fatalf("bad:\n\nexpected:\n%s\n\ngot:\n%s\n", expected, actual)
+	}
+}
+
+func TestTargetsTransformer_include_exclude(t *testing.T) {
+	mod := testModule(t, "transform-targets-basic")
+
+	g := Graph{Path: RootModulePath}
+	{
+		tf := &ConfigTransformer{Module: mod}
+		if err := tf.Transform(&g); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+	}
+
+	{
+		transform := &TargetsTransformer{
+			Targets: []string{
+				"aws_instance.me",
+				"!aws_subnet.me",
+			},
+		}
+		if err := transform.Transform(&g); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+	}
+
+	actual := strings.TrimSpace(g.String())
+	expected := strings.TrimSpace(`
+aws_instance.me
+	`)
+	if actual != expected {
+		t.Fatalf("bad:\n\nexpected:\n%s\n\ngot:\n%s\n", expected, actual)
+	}
+}