suppress dataplex labels (hashicorp#6518)

Signed-off-by: Modular Magician <magic-modules@google.com>

.changelog/6518.txt

@@ -0,0 +1,3 @@
+```release-note:bug
+storage: fixed a bug where user specified labels get overwritten by Dataplex auto generated labels
+```

google/resource_storage_bucket.go

@@ -79,10 +79,12 @@ func resourceStorageBucket() *schema.Resource {
 			},
 
 			"labels": {
-				Type:        schema.TypeMap,
-				Optional:    true,
-				Elem:        &schema.Schema{Type: schema.TypeString},
-				Description: `A set of key/value label pairs to assign to the bucket.`,
+				Type:     schema.TypeMap,
+				Optional: true,
+				// GCP (Dataplex) automatically adds labels
+				DiffSuppressFunc: resourceDataplexLabelDiffSuppress,
+				Elem:             &schema.Schema{Type: schema.TypeString},
+				Description:      `A set of key/value label pairs to assign to the bucket.`,
 			},
 
 			"location": {
@@ -368,6 +370,22 @@ func resourceStorageBucket() *schema.Resource {
 	}
 }
 
+const resourceDataplexGoogleProvidedLabelPrefix = "labels.goog-dataplex"
+
+func resourceDataplexLabelDiffSuppress(k, old, new string, d *schema.ResourceData) bool {
+	if strings.HasPrefix(k, resourceDataplexGoogleProvidedLabelPrefix) && new == "" {
+		return true
+	}
+
+	// Let diff be determined by labels (above)
+	if strings.HasPrefix(k, "labels.%") {
+		return true
+	}
+
+	// For other keys, don't suppress diff.
+	return false
+}
+
 // Is the old bucket retention policy locked?
 func isPolicyLocked(_ context.Context, old, new, _ interface{}) bool {
 	if old == nil || new == nil {

google/resource_storage_bucket_test.go

@@ -1022,6 +1022,85 @@ func TestAccStorageBucket_retentionPolicyLocked(t *testing.T) {
 	})
 }
 
+func TestLabelDiffSuppress(t *testing.T) {
+	cases := map[string]struct {
+		K, Old, New        string
+		ExpectDiffSuppress bool
+	}{
+		"missing goog-dataplex-asset-id": {
+			K:                  "labels.goog-dataplex-asset-id",
+			Old:                "test-bucket",
+			New:                "",
+			ExpectDiffSuppress: true,
+		},
+		"explicit goog-dataplex-asset-id": {
+			K:                  "labels.goog-dataplex-asset-id",
+			Old:                "test-bucket",
+			New:                "test-bucket-1",
+			ExpectDiffSuppress: false,
+		},
+		"missing goog-dataplex-lake-id": {
+			K:                  "labels.goog-dataplex-lake-id",
+			Old:                "test-lake",
+			New:                "",
+			ExpectDiffSuppress: true,
+		},
+		"explicit goog-dataplex-lake-id": {
+			K:                  "labels.goog-dataplex-lake-id",
+			Old:                "test-lake",
+			New:                "test-lake-1",
+			ExpectDiffSuppress: false,
+		},
+		"missing goog-dataplex-project-id": {
+			K:                  "labels.goog-dataplex-project-id",
+			Old:                "test-project-12345",
+			New:                "",
+			ExpectDiffSuppress: true,
+		},
+		"explicit goog-dataplex-project-id": {
+			K:                  "labels.goog-dataplex-project-id",
+			Old:                "test-project-12345",
+			New:                "test-project-12345-1",
+			ExpectDiffSuppress: false,
+		},
+		"missing goog-dataplex-zone-id": {
+			K:                  "labels.goog-dataplex-zone-id",
+			Old:                "test-zone1",
+			New:                "",
+			ExpectDiffSuppress: true,
+		},
+		"explicit goog-dataplex-zone-id": {
+			K:                  "labels.goog-dataplex-zone-id",
+			Old:                "test-zone1",
+			New:                "test-zone1-1",
+			ExpectDiffSuppress: false,
+		},
+		"labels.%": {
+			K:                  "labels.%",
+			Old:                "5",
+			New:                "1",
+			ExpectDiffSuppress: true,
+		},
+		"deleted custom key": {
+			K:                  "labels.my-label",
+			Old:                "my-value",
+			New:                "",
+			ExpectDiffSuppress: false,
+		},
+		"added custom key": {
+			K:                  "labels.my-label",
+			Old:                "",
+			New:                "my-value",
+			ExpectDiffSuppress: false,
+		},
+	}
+	for tn, tc := range cases {
+		if resourceDataplexLabelDiffSuppress(tc.K, tc.Old, tc.New, nil) != tc.ExpectDiffSuppress {
+			t.Errorf("bad: %s, %q: %q => %q expect DiffSuppress to return %t", tn, tc.K, tc.Old, tc.New, tc.ExpectDiffSuppress)
+		}
+	}
+}
+
 func testAccCheckStorageBucketExists(t *testing.T, n string, bucketName string, bucket *storage.Bucket) resource.TestCheckFunc {
 	return func(s *terraform.State) error {
 		rs, ok := s.RootModule().Resources[n]