streams: Add create and edit ui for is_announcement_only.

The user can now specify the value while creating a stream.
An admin can later change it via `Change stream permissions`
modal. Add is_announcement_only to subscription type text.

frontend_tests/node_tests/templates.js

@@ -1259,6 +1259,9 @@ run_test('handlebars_bug', () => {
     assert.equal(other_options[1].value, 'invite-only-public-history');
     assert.equal(other_options[2].value, 'invite-only');
 
+    var is_announcement_only = $(html).find("input[name=is-announcement-only]");
+    assert.equal(is_announcement_only.prop('checked'), false);
+
     var button = $(html).find("#change-stream-privacy-button");
     assert(button.hasClass("btn-danger"));
     assert.equal(button.text().trim(), "translated: Save changes");

static/js/stream_create.js

@@ -98,7 +98,7 @@ var stream_name_error = (function () {
 }());
 
 function ajaxSubscribeForCreation(stream_name, description, principals, invite_only,
-                                  announce, history_public_to_subscribers) {
+                                  is_announcement_only, announce, history_public_to_subscribers) {
     // Subscribe yourself and possible other people to a new stream.
     return channel.post({
         url: "/json/users/me/subscriptions",
@@ -106,6 +106,7 @@ function ajaxSubscribeForCreation(stream_name, description, principals, invite_o
                                                description: description}]),
                principals: JSON.stringify(principals),
                invite_only: JSON.stringify(invite_only),
+               is_announcement_only: JSON.stringify(is_announcement_only),
                announce: JSON.stringify(announce),
                history_public_to_subscribers: JSON.stringify(history_public_to_subscribers),
         },
@@ -171,6 +172,7 @@ function create_stream() {
     var stream_name = $.trim($("#create_stream_name").val());
     var description = $.trim($("#create_stream_description").val());
     var privacy_setting = $('#stream_creation_form input[name=privacy]:checked').val();
+    var is_announcement_only = $('#stream_creation_form input[name=is-announcement-only]').prop('checked');
     var principals = get_principals();
 
     var invite_only;
@@ -199,6 +201,7 @@ function create_stream() {
         description,
         principals,
         invite_only,
+        is_announcement_only,
         announce,
         history_public_to_subscribers
     );

static/js/stream_edit.js

@@ -344,6 +344,7 @@ function change_stream_privacy(e) {
     var sub = stream_data.get_sub_by_id(stream_id);
 
     var privacy_setting = $('#stream_privacy_modal input[name=privacy]:checked').val();
+    var is_announcement_only = $('#stream_privacy_modal input[name=is-announcement-only]').prop('checked');
 
     var invite_only;
     var history_public_to_subscribers;
@@ -364,6 +365,7 @@ function change_stream_privacy(e) {
         stream_name: sub.name,
         // toggle the privacy setting
         is_private: JSON.stringify(invite_only),
+        is_announcement_only: JSON.stringify(is_announcement_only),
         history_public_to_subscribers: JSON.stringify(history_public_to_subscribers),
     };
 
@@ -376,6 +378,7 @@ function change_stream_privacy(e) {
 
             // save new privacy settings.
             sub.invite_only = invite_only;
+            sub.is_announcement_only = is_announcement_only;
             sub.history_public_to_subscribers = history_public_to_subscribers;
 
             redraw_privacy_related_stuff(sub_row, sub);
@@ -508,6 +511,7 @@ exports.initialize = function () {
         var template_data = {
             stream_id: stream_id,
             stream_name: stream.name,
+            is_announcement_only: stream.is_announcement_only,
             is_public: !stream.invite_only,
             is_private: stream.invite_only && !stream.history_public_to_subscribers,
             is_private_with_public_history: (stream.invite_only &&

static/styles/subscriptions.scss

@@ -589,6 +589,10 @@ form#add_new_subscription {
     margin: 5px;
 }
 
+.stream-creation-body #make-invite-only .grey-box .checkbox {
+    margin: 5px;
+}
+
 #announce-new-stream {
     margin-top: 10px;
 }
@@ -962,7 +966,10 @@ form#add_new_subscription {
     padding: 5px 0px;
 }
 
-#stream_privacy_modal ul.grey-box li input[type=checkbox],
+#stream_privacy_modal ul.grey-box li input[type=checkbox] {
+    margin-top: 4px;
+}
+
 #subscription_overlay ul.grey-box li input[type=checkbox] {
     margin-top: 0px;
 }

static/templates/stream_types.handlebars

@@ -23,4 +23,11 @@
             {{/tr}}
         </label>
     </li>
+    <li>
+        <label class="checkbox">
+            <input type="checkbox" name="is-announcement-only" value="is-announcement-only" {{#if is_announcement_only}}checked{{/if}}/>
+            <span></span>
+            {{#tr this}}Restrict posting to organization administrators{{/tr}}
+        </label>
+    </li>
 </ul>

static/templates/subscription_type.handlebars

@@ -6,3 +6,6 @@
 {{else}}
     {{t 'This is a <span class="icon-vector-globe"></span> <b>public stream</b>. Anybody in your organization can join.' }}
 {{/if}}
+{{#if is_announcement_only}}
+{{t 'Only organization administrators can post.'}}
+{{/if}}

zerver/lib/actions.py

@@ -1620,7 +1620,7 @@ def create_stream_if_needed(realm: Realm,
                             stream_name: str,
                             *,
                             invite_only: bool=False,
-                            is_announcement_only: Optional[bool]=False,
+                            is_announcement_only: bool=False,
                             history_public_to_subscribers: Optional[bool]=None,
                             stream_description: str="") -> Tuple[Stream, bool]: