Fix BackendService group hash when instance groups use beta features (#522)

* change backend hash function

* update if statement

google/resource_compute_backend_service.go

@@ -19,6 +19,7 @@ func resourceComputeBackendService() *schema.Resource {
 		Importer: &schema.ResourceImporter{
 			State: schema.ImportStatePassthrough,
 		},
+		SchemaVersion: 1,
 
 		Schema: map[string]*schema.Schema{
 			"name": &schema.Schema{
@@ -42,8 +43,9 @@ func resourceComputeBackendService() *schema.Resource {
 				Elem: &schema.Resource{
 					Schema: map[string]*schema.Schema{
 						"group": &schema.Schema{
-							Type:     schema.TypeString,
-							Optional: true,
+							Type:             schema.TypeString,
+							Required:         true,
+							DiffSuppressFunc: compareSelfLinkRelativePaths,
 						},
 						"balancing_mode": &schema.Schema{
 							Type:     schema.TypeString,
@@ -374,7 +376,8 @@ func resourceGoogleComputeBackendServiceBackendHash(v interface{}) int {
 	var buf bytes.Buffer
 	m := v.(map[string]interface{})
 
-	buf.WriteString(fmt.Sprintf("%s-", m["group"].(string)))
+	group, _ := getRelativePath(m["group"].(string))
+	buf.WriteString(fmt.Sprintf("%s-", group))
 
 	if v, ok := m["balancing_mode"]; ok {
 		buf.WriteString(fmt.Sprintf("%s-", v.(string)))

google/resource_compute_backend_service_migrate.go

@@ -0,0 +1,90 @@
+package google
+
+import (
+	"fmt"
+	"log"
+	"strconv"
+	"strings"
+
+	"github.com/hashicorp/terraform/terraform"
+)
+
+func resourceComputeBackendServiceMigrateState(
+	v int, is *terraform.InstanceState, meta interface{}) (*terraform.InstanceState, error) {
+	if is.Empty() {
+		log.Println("[DEBUG] Empty InstanceState; nothing to migrate.")
+		return is, nil
+	}
+
+	switch v {
+	case 0:
+		log.Println("[INFO] Found Compute Backend Service State v0; migrating to v1")
+		is, err := migrateBackendServiceStateV0toV1(is)
+		if err != nil {
+			return is, err
+		}
+		return is, nil
+	default:
+		return is, fmt.Errorf("Unexpected schema version: %d", v)
+	}
+}
+
+func migrateBackendServiceStateV0toV1(is *terraform.InstanceState) (*terraform.InstanceState, error) {
+	log.Printf("[DEBUG] Attributes before migration: %#v", is.Attributes)
+
+	oldHashToValue := map[string]map[string]interface{}{}
+	for k, v := range is.Attributes {
+		if !strings.HasPrefix(k, "backend.") || k == "backend.#" {
+			continue
+		}
+
+		// Key is now of the form backend.%d.%s
+		kParts := strings.Split(k, ".")
+
+		// Sanity check: two parts should be there and <N> should be a number
+		badFormat := false
+		if len(kParts) != 3 {
+			badFormat = true
+		} else if _, err := strconv.Atoi(kParts[1]); err != nil {
+			badFormat = true
+		}
+
+		if badFormat {
+			return is, fmt.Errorf("migration error: found backend key in unexpected format: %s", k)
+		}
+
+		if oldHashToValue[kParts[1]] == nil {
+			oldHashToValue[kParts[1]] = map[string]interface{}{}
+		}
+		oldHashToValue[kParts[1]][kParts[2]] = v
+	}
+
+	oldHashToNewHash := map[string]int{}
+	for k, v := range oldHashToValue {
+		oldHashToNewHash[k] = resourceGoogleComputeBackendServiceBackendHash(v)
+	}
+
+	values := map[string]string{}
+	for k, v := range is.Attributes {
+		if !strings.HasPrefix(k, "backend.") {
+			continue
+		}
+
+		if k == "backend.#" {
+			continue
+		}
+
+		// Key is now of the form backend.%d.%s
+		kParts := strings.Split(k, ".")
+		newKey := fmt.Sprintf("%s.%d.%s", kParts[0], oldHashToNewHash[kParts[1]], kParts[2])
+		values[newKey] = v
+		delete(is.Attributes, k)
+	}
+
+	for k, v := range values {
+		is.Attributes[k] = v
+	}
+
+	log.Printf("[DEBUG] Attributes after migration: %#v", is.Attributes)
+	return is, nil
+}

google/resource_compute_backend_service_migrate_test.go

@@ -0,0 +1,95 @@
+package google
+
+import (
+	"testing"
+
+	"github.com/hashicorp/terraform/terraform"
+)
+
+func TestComputeBackendServiceMigrateState(t *testing.T) {
+	cases := map[string]struct {
+		StateVersion       int
+		Attributes         map[string]string
+		ExpectedAttributes map[string]string
+		Meta               interface{}
+	}{
+		"v0 to v1": {
+			StateVersion: 0,
+			Attributes: map[string]string{
+				"backend.#":                         "1",
+				"backend.242332812.group":           "https://www.googleapis.com/compute/v1/projects/project_name/zones/zone_name/instances/instanceGroups/igName",
+				"backend.242332812.balancing_mode":  "UTILIZATION",
+				"backend.242332812.max_utilization": "0.8",
+			},
+			ExpectedAttributes: map[string]string{
+				"backend.#":                          "1",
+				"backend.2573491210.group":           "https://www.googleapis.com/compute/v1/projects/project_name/zones/zone_name/instances/instanceGroups/igName",
+				"backend.2573491210.balancing_mode":  "UTILIZATION",
+				"backend.2573491210.max_utilization": "0.8",
+			},
+			Meta: &Config{},
+		},
+	}
+
+	for tn, tc := range cases {
+		is := &terraform.InstanceState{
+			ID:         "i-abc123",
+			Attributes: tc.Attributes,
+		}
+		is, err := resourceComputeBackendServiceMigrateState(
+			tc.StateVersion, is, tc.Meta)
+
+		if err != nil {
+			t.Fatalf("bad: %s, err: %#v", tn, err)
+		}
+
+		for k, v := range tc.ExpectedAttributes {
+			if is.Attributes[k] != v {
+				t.Fatalf(
+					"bad: %s\n\n expected: %#v -> %#v\n got: %#v -> %#v\n in: %#v",
+					tn, k, v, k, is.Attributes[k], is.Attributes)
+			}
+		}
+
+		for k, v := range is.Attributes {
+			if tc.ExpectedAttributes[k] != v {
+				t.Fatalf(
+					"bad: %s\n\n expected: %#v -> %#v\n got: %#v -> %#v\n in: %#v",
+					tn, k, tc.ExpectedAttributes[k], k, v, is.Attributes)
+			}
+		}
+	}
+}
+
+func TestComputeBackendServiceMigrateState_empty(t *testing.T) {
+	cases := map[string]struct {
+		StateVersion int
+	}{
+		"v0": {
+			StateVersion: 0,
+		},
+	}
+
+	for tn, tc := range cases {
+		var is *terraform.InstanceState
+		var meta *Config
+
+		// should handle nil
+		is, err := resourceComputeBackendServiceMigrateState(tc.StateVersion, is, meta)
+
+		if err != nil {
+			t.Fatalf("bad %s, err: %#v", tn, err)
+		}
+		if is != nil {
+			t.Fatalf("bad %s, expected nil instancestate, got: %#v", tn, is)
+		}
+
+		// should handle non-nil but empty
+		is = &terraform.InstanceState{}
+		is, err = resourceComputeBackendServiceMigrateState(tc.StateVersion, is, meta)
+
+		if err != nil {
+			t.Fatalf("bad %s, err: %#v", tn, err)
+		}
+	}
+}

google/resource_compute_backend_service_test.go

@@ -412,6 +412,10 @@ resource "google_compute_instance_group_manager" "foobar" {
   base_instance_name = "foobar"
   zone               = "us-central1-f"
   target_size        = 1
+  auto_healing_policies {
+    health_check = "${google_compute_http_health_check.default.self_link}"
+    initial_delay_sec = "10"
+  }
 }
 
 resource "google_compute_instance_template" "foobar" {