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puppeteer-core

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A high-level API to control headless Chrome over the DevTools Protocol

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"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.Tracing = void 0; /** * 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 assert_js_1 = require("./assert.js"); const helper_js_1 = require("./helper.js"); /** * The Tracing class exposes the tracing audit interface. * @remarks * You can use `tracing.start` and `tracing.stop` to create a trace file * which can be opened in Chrome DevTools or {@link https://chromedevtools.github.io/timeline-viewer/ | timeline viewer}. * * @example * ```js * await page.tracing.start({path: 'trace.json'}); * await page.goto('https://www.google.com'); * await page.tracing.stop(); * ``` * * @public */ class Tracing { /** * @internal */ constructor(client) { this._recording = false; this._path = ''; this._client = client; } /** * Starts a trace for the current page. * @remarks * Only one trace can be active at a time per browser. * @param options - Optional `TracingOptions`. */ async start(options = {}) { (0, assert_js_1.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', ]; const { path = null, screenshots = false, categories = defaultCategories, } = options; if (screenshots) categories.push('disabled-by-default-devtools.screenshot'); const excludedCategories = categories .filter((cat) => cat.startsWith('-')) .map((cat) => cat.slice(1)); const includedCategories = categories.filter((cat) => !cat.startsWith('-')); this._path = path; this._recording = true; await this._client.send('Tracing.start', { transferMode: 'ReturnAsStream', traceConfig: { excludedCategories, includedCategories, }, }); } /** * Stops a trace started with the `start` method. * @returns Promise which resolves to buffer with trace data. */ async stop() { let fulfill; let reject; const contentPromise = new Promise((x, y) => { fulfill = x; reject = y; }); this._client.once('Tracing.tracingComplete', async (event) => { try { const readable = await helper_js_1.helper.getReadableFromProtocolStream(this._client, event.stream); const buffer = await helper_js_1.helper.getReadableAsBuffer(readable, this._path); fulfill(buffer); } catch (error) { reject(error); } }); await this._client.send('Tracing.end'); this._recording = false; return contentPromise; } } exports.Tracing = Tracing; //# sourceMappingURL=Tracing.js.map