feat: add new FieldBehavior value IDENTIFIER

Google APIs · copybara-github · commit f5987af9df62 · 2023-08-22T08:30:36.000-07:00
PiperOrigin-RevId: 559119958
diff --git a/google/api/field_behavior.proto b/google/api/field_behavior.proto
@@ -87,4 +87,18 @@ enum FieldBehavior {
   // a non-empty value will be returned. The user will not be aware of what
   // non-empty value to expect.
   NON_EMPTY_DEFAULT = 7;
+
+  // Denotes that the field in a resource (a message annotated with
+  // google.api.resource) is used in the resource name to uniquely identify the
+  // resource. For AIP-compliant APIs, this should only be applied to the
+  // `name` field on the resource.
+  //
+  // This behavior should not be applied to references to other resources within
+  // the message.
+  //
+  // The identifier field of resources often have different field behavior
+  // depending on the request it is embedded in (e.g. for Create methods name
+  // is optional and unused, while for Update methods it is required). Instead
+  // of method-specific annotations, only `IDENTIFIER` is required.
+  IDENTIFIER = 8;
 }
