Add diff suppress for time format to google_compute_resource_policies

.changelog/11486.txt

@@ -0,0 +1,3 @@
+```release-note:enhancement
+compute: fixed a permadiff caused by setting `start_time` in an incorrect H:mm format in `google_compute_resource_policies` resources
+```

google-beta/services/compute/resource_compute_resource_policy.go

@@ -32,6 +32,12 @@ import (
 	"github.com/hashicorp/terraform-provider-google-beta/google-beta/verify"
 )
 
+// Suppresses a diff on cases like 1:00 when it should be 01:00.
+// Because API will normalize this value
+func HourlyFormatSuppressDiff(_, old, new string, _ *schema.ResourceData) bool {
+	return old == "0"+new
+}
+
 func ResourceComputeResourcePolicy() *schema.Resource {
 	return &schema.Resource{
 		Create: resourceComputeResourcePolicyCreate,
@@ -220,9 +226,10 @@ from the tz database: http://en.wikipedia.org/wiki/Tz_database.`,
 													Description: `Defines a schedule with units measured in days. The value determines how many days pass between the start of each cycle. Days in cycle for snapshot schedule policy must be 1.`,
 												},
 												"start_time": {
-													Type:         schema.TypeString,
-													Required:     true,
-													ValidateFunc: verify.ValidateHourlyOnly,
+													Type:             schema.TypeString,
+													Required:         true,
+													ValidateFunc:     verify.ValidateHourlyOnly,
+													DiffSuppressFunc: HourlyFormatSuppressDiff,
 													Description: `This must be in UTC format that resolves to one of
 00:00, 04:00, 08:00, 12:00, 16:00, or 20:00. For example,
 both 13:00-5 and 08:00 are valid.`,
@@ -244,9 +251,10 @@ both 13:00-5 and 08:00 are valid.`,
 													Description: `The number of hours between snapshots.`,
 												},
 												"start_time": {
-													Type:         schema.TypeString,
-													Required:     true,
-													ValidateFunc: verify.ValidateHourlyOnly,
+													Type:             schema.TypeString,
+													Required:         true,
+													ValidateFunc:     verify.ValidateHourlyOnly,
+													DiffSuppressFunc: HourlyFormatSuppressDiff,
 													Description: `Time within the window to start the operations.
 It must be in an hourly format "HH:MM",
 where HH : [00-23] and MM : [00] GMT. eg: 21:00`,

google-beta/services/compute/resource_compute_resource_policy_generated_test.go

@@ -72,6 +72,48 @@ resource "google_compute_resource_policy" "foo" {
 `, context)
 }
 
+func TestAccComputeResourcePolicy_resourcePolicyHourlyFormatExample(t *testing.T) {
+	t.Parallel()
+
+	context := map[string]interface{}{
+		"random_suffix": acctest.RandString(t, 10),
+	}
+
+	acctest.VcrTest(t, resource.TestCase{
+		PreCheck:                 func() { acctest.AccTestPreCheck(t) },
+		ProtoV5ProviderFactories: acctest.ProtoV5ProviderFactories(t),
+		CheckDestroy:             testAccCheckComputeResourcePolicyDestroyProducer(t),
+		Steps: []resource.TestStep{
+			{
+				Config: testAccComputeResourcePolicy_resourcePolicyHourlyFormatExample(context),
+			},
+			{
+				ResourceName:            "google_compute_resource_policy.foo",
+				ImportState:             true,
+				ImportStateVerify:       true,
+				ImportStateVerifyIgnore: []string{"region"},
+			},
+		},
+	})
+}
+
+func testAccComputeResourcePolicy_resourcePolicyHourlyFormatExample(context map[string]interface{}) string {
+	return acctest.Nprintf(`
+resource "google_compute_resource_policy" "foo" {
+  name   = "tf-test-gce-policy%{random_suffix}"
+  region = "us-central1"
+  snapshot_schedule_policy {
+    schedule {
+      daily_schedule {
+        days_in_cycle = 1
+        start_time    = "4:00"
+      }
+    }
+  }
+}
+`, context)
+}
+
 func TestAccComputeResourcePolicy_resourcePolicyFullExample(t *testing.T) {
 	t.Parallel()
 

google-beta/services/compute/resource_compute_resource_policy_test.go

@@ -8,8 +8,49 @@ import (
 
 	"github.com/hashicorp/terraform-plugin-testing/helper/resource"
 	"github.com/hashicorp/terraform-provider-google-beta/google-beta/acctest"
+	"github.com/hashicorp/terraform-provider-google-beta/google-beta/services/compute"
 )
 
+// Value returned from the API will always be in format "HH:MM", so we need the suppress only on new values
+func TestHourlyFormatSuppressDiff(t *testing.T) {
+	cases := map[string]struct {
+		Old, New           string
+		ExpectDiffSuppress bool
+	}{
+		"Same value": {
+			Old:                "01:00",
+			New:                "01:00",
+			ExpectDiffSuppress: false,
+		},
+		"Same value but different format": {
+			Old:                "01:00",
+			New:                "1:00",
+			ExpectDiffSuppress: true,
+		},
+		"Changed value": {
+			Old:                "01:00",
+			New:                "02:00",
+			ExpectDiffSuppress: false,
+		},
+		"Changed value but different format": {
+			Old:                "01:00",
+			New:                "2:00",
+			ExpectDiffSuppress: false,
+		},
+		"Check interference with unaffected values": {
+			Old:                "11:00",
+			New:                "22:00",
+			ExpectDiffSuppress: false,
+		},
+	}
+
+	for tn, tc := range cases {
+		if compute.HourlyFormatSuppressDiff("", tc.Old, tc.New, nil) != tc.ExpectDiffSuppress {
+			t.Errorf("bad: %s, %q => %q expect DiffSuppress to return %t", tn, tc.Old, tc.New, tc.ExpectDiffSuppress)
+		}
+	}
+}
+
 func TestAccComputeResourcePolicy_attached(t *testing.T) {
 	t.Parallel()