api: Add updateUserTopic route

Author: gnprice

src/api/index.js

@@ -50,6 +50,7 @@ import subscriptionRemove from './subscriptions/subscriptionRemove';
 import setSubscriptionProperty from './subscriptions/setSubscriptionProperty';
 import getSubscriptionToStream from './subscriptions/getSubscriptionToStream';
 import setTopicMute from './subscriptions/setTopicMute';
+import updateUserTopic from './subscriptions/updateUserTopic';
 import tryGetFileTemporaryUrl from './tryGetFileTemporaryUrl';
 import getUsers from './users/getUsers';
 import createUser from './users/createUser';
@@ -98,6 +99,7 @@ export {
   sendSubmessage,
   getSubscriptions,
   setTopicMute,
+  updateUserTopic,
   subscriptionAdd,
   subscriptionRemove,
   setSubscriptionProperty,

src/api/subscriptions/updateUserTopic.js

@@ -0,0 +1,18 @@
+// @flow strict-local
+import type { UserTopicVisibilityPolicy } from '../modelTypes';
+import type { ApiResponseSuccess, Auth } from '../transportTypes';
+import { apiPost } from '../apiFetch';
+
+/** https://chat.zulip.org/api/update-user-topic */
+export default function updateUserTopic(
+  auth: Auth,
+  stream_id: number,
+  topic: string,
+  visibility_policy: UserTopicVisibilityPolicy,
+): Promise<ApiResponseSuccess> {
+  return apiPost(auth, '/user_topics', {
+    stream_id,
+    topic,
+    visibility_policy: (visibility_policy: number),
+  });
+}