org settings: Explain Zoom support is experimental, and fix a few strings.

Visually, #zoom_help_text acts like
.organization-settings-parent div:first-of-type when the Zoom option
is selected, but isn't treated as such.

No visual change with the #google_hangouts_domain change; just there to make
the code more readable/defensible.

docs/overview/changelog.md

@@ -15,8 +15,8 @@ in bursts.
 - Added support for explicitly setting oneself as "away" and "user
   status" messages.
 - Added a built-in /poll slash command for lightweight polls.
-- Added support for using Zoom as the video chat provider.  We now
-  support Jitsi, Google Hangouts, and Zoom.
+- Added experimental support for using Zoom as the video chat
+  provider.  We now support Jitsi, Google Hangouts, and Zoom.
 - Added support for branding the top-left corner of the logged in app
   with an organization's logo.
 - Zulip's "Guest users" feature is no longer experimental.

static/styles/settings.scss

@@ -478,6 +478,8 @@ input[type=checkbox] + .inline-block {
     display: none;
 }
 
+#google_hangouts_domain,
+#zoom_help_text,
 .organization-settings-parent div:first-of-type {
     margin-top: 10px;
 }

static/templates/settings/organization-settings-admin.handlebars

@@ -165,8 +165,14 @@
                           name="realm_google_hangouts_domain"
                           class="admin-realm-google-hangouts-domain"/>
                     </div>
+                    <div id="zoom_help_text" class="zoom_credentials">
+                        <p>
+                            Note: Zoom support is experimental. In particular, Zulip currently supports having
+                            only one active Zoom meeting at a time.
+                        </p>
+                    </div>
                     <div id="zoom_user_id" class="zoom_credentials">
-                        <label>{{t 'Zoom user ID (required)' }}:</label>
+                        <label>{{t 'Zoom user ID or email address (required)' }}:</label>
                         <input type="text" id="id_realm_zoom_user_id"
                           name="realm_zoom_user_id"
                           class="admin-realm-zoom-field"/>

zerver/tests/test_realm.py

@@ -414,14 +414,14 @@ class RealmTest(ZulipTestCase):
 
         req = {"video_chat_provider": ujson.dumps("Zoom")}
         result = self.client_patch('/json/realm', req)
-        self.assert_json_error(result, "Invalid user ID: user ID cannot be empty")
+        self.assert_json_error(result, "User ID cannot be empty")
 
         req = {
             "video_chat_provider": ujson.dumps("Zoom"),
             "zoom_user_id": ujson.dumps("example@example.com")
         }
         result = self.client_patch('/json/realm', req)
-        self.assert_json_error(result, "Invalid API key: API key cannot be empty")
+        self.assert_json_error(result, "API key cannot be empty")
 
         req = {
             "video_chat_provider": ujson.dumps("Zoom"),
@@ -429,7 +429,7 @@ class RealmTest(ZulipTestCase):
             "zoom_api_key": ujson.dumps("abc")
         }
         result = self.client_patch('/json/realm', req)
-        self.assert_json_error(result, "Invalid API secret: API secret cannot be empty")
+        self.assert_json_error(result, "API secret cannot be empty")
 
         with mock.patch("zerver.views.realm.request_zoom_video_call_url", return_value=None):
             req = {

zerver/views/realm.py

@@ -87,11 +87,11 @@ def update_realm(
             return json_error(_('Invalid domain: {}').format(e.messages[0]))
     if video_chat_provider == "Zoom":
         if not zoom_user_id:
-            return json_error(_('Invalid user ID: user ID cannot be empty'))
+            return json_error(_('User ID cannot be empty'))
         if not zoom_api_key:
-            return json_error(_('Invalid API key: API key cannot be empty'))
+            return json_error(_('API key cannot be empty'))
         if not zoom_api_secret:
-            return json_error(_('Invalid API secret: API secret cannot be empty'))
+            return json_error(_('API secret cannot be empty'))
         # Technically, we could call some other API endpoint that
         # doesn't create a video call link, but this is a nicer
         # end-to-end test, since it verifies that the Zoom API user's