xref: /aosp_15_r20/external/perfetto/ui/src/core/channels.ts (revision 6dbdd20afdafa5e3ca9b8809fa73465d530080dc)
1// Copyright (C) 2021 The Android Open Source Project
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//      http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15import {raf} from './raf_scheduler';
16
17export const DEFAULT_CHANNEL = 'stable';
18const CHANNEL_KEY = 'perfettoUiChannel';
19
20let currentChannel: string | undefined = undefined;
21let nextChannel: string | undefined = undefined;
22
23// This is the channel the UI is currently running. It doesn't change once the
24// UI has been loaded.
25export function getCurrentChannel(): string {
26  if (currentChannel === undefined) {
27    currentChannel = localStorage.getItem(CHANNEL_KEY) ?? DEFAULT_CHANNEL;
28  }
29  return currentChannel;
30}
31
32// This is the channel that will be applied on reload.
33export function getNextChannel(): string {
34  if (nextChannel !== undefined) {
35    return nextChannel;
36  }
37  return getCurrentChannel();
38}
39
40export function channelChanged(): boolean {
41  return getCurrentChannel() !== getNextChannel();
42}
43
44export function setChannel(channel: string): void {
45  getCurrentChannel(); // Cache the current channel before mangling next one.
46  nextChannel = channel;
47  localStorage.setItem(CHANNEL_KEY, channel);
48  raf.scheduleFullRedraw();
49}
50