stream_data: Remove page_params.notifications_stream.

We shouldn't add redundant data to page_params. Since we already have
page_params.realm_notifications_stream_id, we can use that value instead
of creating page_params.notifications_stream.

We, however, still need the name of the notifications stream to render
it in templates. Thus we create stream_data.get_notifications_stream().

frontend_tests/node_tests/stream_data.js

@@ -775,21 +775,21 @@ run_test('notifications', () => {
     assert.deepEqual(unmatched_streams, expected_streams);
 });
 
+const tony = {
+    stream_id: 999,
+    name: 'tony',
+    subscribed: true,
+    is_muted: false,
+};
+
+const jazy = {
+    stream_id: 500,
+    name: 'jazy',
+    subscribed: false,
+    is_muted: true,
+};
+
 run_test('is_muted', () => {
-    const tony = {
-        stream_id: 999,
-        name: 'tony',
-        subscribed: true,
-        is_muted: false,
-    };
-
-    const jazy = {
-        stream_id: 500,
-        name: 'jazy',
-        subscribed: false,
-        is_muted: true,
-    };
-
     stream_data.add_sub(tony);
     stream_data.add_sub(jazy);
     assert(!stream_data.is_stream_muted_by_name('tony'));
@@ -798,10 +798,13 @@ run_test('is_muted', () => {
 });
 
 run_test('is_notifications_stream_muted', () => {
-    page_params.notifications_stream = 'tony';
+    stream_data.add_sub(tony);
+    stream_data.add_sub(jazy);
+
+    page_params.realm_notifications_stream_id = tony.stream_id;
     assert(!stream_data.is_notifications_stream_muted());
 
-    page_params.notifications_stream = 'jazy';
+    page_params.realm_notifications_stream_id = jazy.stream_id;
     assert(stream_data.is_notifications_stream_muted());
 });
 
@@ -904,12 +907,12 @@ run_test('initialize', () => {
     assert(stream_names.includes('subscriptions'));
     assert(stream_names.includes('unsubscribed'));
     assert(stream_names.includes('never_subscribed'));
-    assert.equal(page_params.notifications_stream, "");
+    assert.equal(stream_data.get_notifications_stream(), "");
 
     // Simulate a private stream the user isn't subscribed to
     page_params.realm_notifications_stream_id = 89;
     initialize();
-    assert.equal(page_params.notifications_stream, "");
+    assert.equal(stream_data.get_notifications_stream(), "");
 
     // Now actually subscribe the user to the stream
     initialize();
@@ -920,7 +923,7 @@ run_test('initialize', () => {
 
     stream_data.add_sub(foo);
     initialize();
-    assert.equal(page_params.notifications_stream, "foo");
+    assert.equal(stream_data.get_notifications_stream(), "foo");
 });
 
 run_test('filter inactives', () => {

static/js/invite.js

@@ -135,7 +135,7 @@ exports.get_invite_streams = function () {
 function update_subscription_checkboxes() {
     const data = {
         streams: exports.get_invite_streams(),
-        notifications_stream: page_params.notifications_stream,
+        notifications_stream: stream_data.get_notifications_stream(),
     };
     const html = render_invite_subscription(data);
     $('#streams_to_add').html(html);

static/js/stream_create.js

@@ -101,7 +101,7 @@ const stream_name_error = (function () {
 function update_announce_stream_state() {
 
     // If there is no notifications_stream, we simply hide the widget.
-    if (!page_params.notifications_stream) {
+    if (page_params.realm_notifications_stream_id === -1) {
         $('#announce-new-stream').hide();
         return;
     }
@@ -174,7 +174,7 @@ function create_stream() {
     }
     data.stream_post_policy = JSON.stringify(stream_post_policy);
 
-    const announce = !!page_params.notifications_stream &&
+    const announce = page_params.realm_notifications_stream_id !== -1 &&
         $('#announce-new-stream input').prop('checked');
     data.announce = JSON.stringify(announce);
 
@@ -274,7 +274,7 @@ exports.show_new_stream_modal = function () {
     // public, "announce stream" on.
     $('#make-invite-only input:radio[value=public]').prop('checked', true);
 
-    if (page_params.notifications_stream) {
+    if (page_params.realm_notifications_stream_id !== -1) {
         $('#announce-new-stream').show();
         $('#announce-new-stream input').prop('disabled', false);
         $('#announce-new-stream input').prop('checked', true);
@@ -437,7 +437,8 @@ exports.set_up_handlers = function () {
         announce_stream_docs.popover({
             placement: "right",
             content: render_announce_stream_docs({
-                notifications_stream: page_params.notifications_stream}),
+                notifications_stream: stream_data.get_notifications_stream(),
+            }),
             html: true,
             trigger: "manual"});
         announce_stream_docs.popover('show');

static/js/stream_data.js

@@ -512,8 +512,7 @@ exports.is_stream_muted_by_name = function (stream_name) {
 };
 
 exports.is_notifications_stream_muted = function () {
-    // TODO: add page_params.notifications_stream_id
-    return exports.is_stream_muted_by_name(page_params.notifications_stream);
+    return exports.is_muted(page_params.realm_notifications_stream_id);
 };
 
 exports.is_subscribed = function (stream_name) {
@@ -865,6 +864,19 @@ exports.get_streams_for_admin = function () {
     return subs;
 };
 
+exports.get_notifications_stream = function () {
+    const stream_id = page_params.realm_notifications_stream_id;
+    if (stream_id !== -1) {
+        const stream_obj = exports.get_sub_by_id(stream_id);
+        if (stream_obj) {
+            return stream_obj.name;
+        }
+        // We reach here when the notifications stream is a private
+        // stream the current user is not subscribed to.
+    }
+    return '';
+};
+
 exports.initialize = function (params) {
     /*
         We get `params` data, which is data that we "own"
@@ -904,22 +916,6 @@ exports.initialize = function (params) {
     populate_subscriptions(unsubscribed, false, true);
     populate_subscriptions(never_subscribed, false, false);
 
-    // Migrate the notifications stream from the new API structure to
-    // what the frontend expects.
-    if (page_params.realm_notifications_stream_id !== -1) {
-        const notifications_stream_obj =
-            exports.get_sub_by_id(page_params.realm_notifications_stream_id);
-        if (notifications_stream_obj) {
-            // This happens when the notifications stream is a private
-            // stream the current user is not subscribed to.
-            page_params.notifications_stream = notifications_stream_obj.name;
-        } else {
-            page_params.notifications_stream = "";
-        }
-    } else {
-        page_params.notifications_stream = "";
-    }
-
     exports.set_filter_out_inactives();
 };