puppeteer/src/common/Tracing.ts
Jack Franklin 9522f80116
chore: create common directory (#6042)
These files will be used by both the web and node versions of Puppeteer.
Another name for this might be "core" but I don't want to cause
confusion with the puppeteer-core package that we publish at the moment.
2020-06-18 15:53:23 +01:00

84 lines
2.3 KiB
TypeScript

/**
* Copyright 2017 Google Inc. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import { assert } from './assert';
import { helper } from './helper';
import { CDPSession } from './Connection';
interface TracingOptions {
path?: string;
screenshots?: boolean;
categories?: string[];
}
export class Tracing {
_client: CDPSession;
_recording = false;
_path = '';
constructor(client: CDPSession) {
this._client = client;
}
async start(options: TracingOptions = {}): Promise<void> {
assert(
!this._recording,
'Cannot start recording trace while already recording trace.'
);
const defaultCategories = [
'-*',
'devtools.timeline',
'v8.execute',
'disabled-by-default-devtools.timeline',
'disabled-by-default-devtools.timeline.frame',
'toplevel',
'blink.console',
'blink.user_timing',
'latencyInfo',
'disabled-by-default-devtools.timeline.stack',
'disabled-by-default-v8.cpu_profiler',
'disabled-by-default-v8.cpu_profiler.hires',
];
const {
path = null,
screenshots = false,
categories = defaultCategories,
} = options;
if (screenshots) categories.push('disabled-by-default-devtools.screenshot');
this._path = path;
this._recording = true;
await this._client.send('Tracing.start', {
transferMode: 'ReturnAsStream',
categories: categories.join(','),
});
}
async stop(): Promise<Buffer> {
let fulfill: (value: Buffer) => void;
const contentPromise = new Promise<Buffer>((x) => (fulfill = x));
this._client.once('Tracing.tracingComplete', (event) => {
helper
.readProtocolStream(this._client, event.stream, this._path)
.then(fulfill);
});
await this._client.send('Tracing.end');
this._recording = false;
return contentPromise;
}
}