90 lines
2.6 KiB
JavaScript
90 lines
2.6 KiB
JavaScript
/**
|
|
* 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.
|
|
*/
|
|
const fs = require('fs');
|
|
const helper = require('./helper');
|
|
|
|
class Tracing {
|
|
/**
|
|
* @param {!Connection} client
|
|
*/
|
|
constructor(client) {
|
|
this._client = client;
|
|
this._recording = false;
|
|
this._path = '';
|
|
}
|
|
|
|
/**
|
|
* @param {!Object} options
|
|
* @return {!Promise}
|
|
*/
|
|
async start(options) {
|
|
console.assert(!this._recording, 'Cannot start recording trace while already recording trace.');
|
|
console.assert(options.path, 'Must specify a path to write trace file to.');
|
|
|
|
const categoriesArray = [
|
|
'-*', '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'
|
|
];
|
|
|
|
if (options.screenshots)
|
|
categoriesArray.push('disabled-by-default-devtools.screenshot');
|
|
|
|
this._path = options.path;
|
|
this._recording = true;
|
|
await this._client.send('Tracing.start', {
|
|
transferMode: 'ReturnAsStream',
|
|
categories: categoriesArray.join(',')
|
|
});
|
|
}
|
|
|
|
/**
|
|
* @return {!Promise}
|
|
*/
|
|
async stop() {
|
|
let fulfill;
|
|
let contentPromise = new Promise(x => fulfill = x);
|
|
this._client.once('Tracing.tracingComplete', event => {
|
|
this._readStream(event.stream, this._path).then(fulfill);
|
|
});
|
|
await this._client.send('Tracing.end');
|
|
this._recording = false;
|
|
return contentPromise;
|
|
}
|
|
|
|
/**
|
|
* @param {string} handle
|
|
* @param {string} path
|
|
* @return {!Promise}
|
|
*/
|
|
async _readStream(handle, path) {
|
|
let eof = false;
|
|
let file = fs.openSync(path, 'w');
|
|
while (!eof) {
|
|
let response = await this._client.send('IO.read', {handle});
|
|
eof = response.eof;
|
|
if (path)
|
|
fs.writeSync(file, response.data);
|
|
}
|
|
fs.closeSync(file);
|
|
await this._client.send('IO.close', {handle});
|
|
}
|
|
}
|
|
helper.tracePublicAPI(Tracing);
|
|
|
|
module.exports = Tracing;
|