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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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/** * Copyright 2019 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. */ var __classPrivateFieldGet = (this && this.__classPrivateFieldGet) || function (receiver, state, kind, f) { if (kind === "a" && !f) throw new TypeError("Private accessor was defined without a getter"); if (typeof state === "function" ? receiver !== state || !f : !state.has(receiver)) throw new TypeError("Cannot read private member from an object whose class did not declare it"); return kind === "m" ? f : kind === "a" ? f.call(receiver) : f ? f.value : state.get(receiver); }; var __classPrivateFieldSet = (this && this.__classPrivateFieldSet) || function (receiver, state, value, kind, f) { if (kind === "m") throw new TypeError("Private method is not writable"); if (kind === "a" && !f) throw new TypeError("Private accessor was defined without a setter"); if (typeof state === "function" ? receiver !== state || !f : !state.has(receiver)) throw new TypeError("Cannot write private member to an object whose class did not declare it"); return (kind === "a" ? f.call(receiver, value) : f ? f.value = value : state.set(receiver, value)), value; }; var _JSHandle_disposed, _JSHandle_context, _JSHandle_remoteObject; import { assert } from '../util/assert.js'; import { createJSHandle, releaseObject, valueFromRemoteObject } from './util.js'; /** * Represents a reference to a JavaScript object. Instances can be created using * {@link Page.evaluateHandle}. * * Handles prevent the referenced JavaScript object from being garbage-collected * unless the handle is purposely {@link JSHandle.dispose | disposed}. JSHandles * are auto-disposed when their associated frame is navigated away or the parent * context gets destroyed. * * Handles can be used as arguments for any evaluation function such as * {@link Page.$eval}, {@link Page.evaluate}, and {@link Page.evaluateHandle}. * They are resolved to their referenced object. * * @example * * ```ts * const windowHandle = await page.evaluateHandle(() => window); * ``` * * @public */ export class JSHandle { /** * @internal */ get client() { return __classPrivateFieldGet(this, _JSHandle_context, "f")._client; } /** * @internal */ get disposed() { return __classPrivateFieldGet(this, _JSHandle_disposed, "f"); } /** * @internal */ constructor(context, remoteObject) { _JSHandle_disposed.set(this, false); _JSHandle_context.set(this, void 0); _JSHandle_remoteObject.set(this, void 0); __classPrivateFieldSet(this, _JSHandle_context, context, "f"); __classPrivateFieldSet(this, _JSHandle_remoteObject, remoteObject, "f"); } /** * @internal */ executionContext() { return __classPrivateFieldGet(this, _JSHandle_context, "f"); } /** * Evaluates the given function with the current handle as its first argument. * * @see {@link ExecutionContext.evaluate} for more details. */ async evaluate(pageFunction, ...args) { return await this.executionContext().evaluate(pageFunction, this, ...args); } /** * Evaluates the given function with the current handle as its first argument. * * @see {@link ExecutionContext.evaluateHandle} for more details. */ async evaluateHandle(pageFunction, ...args) { return await this.executionContext().evaluateHandle(pageFunction, this, ...args); } async getProperty(propertyName) { return this.evaluateHandle((object, propertyName) => { return object[propertyName]; }, propertyName); } /** * Gets a map of handles representing the properties of the current handle. * * @example * * ```ts * const listHandle = await page.evaluateHandle(() => document.body.children); * const properties = await listHandle.getProperties(); * const children = []; * for (const property of properties.values()) { * const element = property.asElement(); * if (element) { * children.push(element); * } * } * children; // holds elementHandles to all children of document.body * ``` */ async getProperties() { assert(__classPrivateFieldGet(this, _JSHandle_remoteObject, "f").objectId); // We use Runtime.getProperties rather than iterative building because the // iterative approach might create a distorted snapshot. const response = await this.client.send('Runtime.getProperties', { objectId: __classPrivateFieldGet(this, _JSHandle_remoteObject, "f").objectId, ownProperties: true, }); const result = new Map(); for (const property of response.result) { if (!property.enumerable || !property.value) { continue; } result.set(property.name, createJSHandle(__classPrivateFieldGet(this, _JSHandle_context, "f"), property.value)); } return result; } /** * @returns A vanilla object representing the serializable portions of the * referenced object. * @throws Throws if the object cannot be serialized due to circularity. * * @remarks * If the object has a `toJSON` function, it **will not** be called. */ async jsonValue() { if (!__classPrivateFieldGet(this, _JSHandle_remoteObject, "f").objectId) { return valueFromRemoteObject(__classPrivateFieldGet(this, _JSHandle_remoteObject, "f")); } const value = await this.evaluate(object => { return object; }); if (value === undefined) { throw new Error('Could not serialize referenced object'); } return value; } /** * @returns Either `null` or the handle itself if the handle is an * instance of {@link ElementHandle}. */ asElement() { return null; } /** * Releases the object referenced by the handle for garbage collection. */ async dispose() { if (__classPrivateFieldGet(this, _JSHandle_disposed, "f")) { return; } __classPrivateFieldSet(this, _JSHandle_disposed, true, "f"); await releaseObject(this.client, __classPrivateFieldGet(this, _JSHandle_remoteObject, "f")); } /** * Returns a string representation of the JSHandle. * * @remarks * Useful during debugging. */ toString() { if (!__classPrivateFieldGet(this, _JSHandle_remoteObject, "f").objectId) { return 'JSHandle:' + valueFromRemoteObject(__classPrivateFieldGet(this, _JSHandle_remoteObject, "f")); } const type = __classPrivateFieldGet(this, _JSHandle_remoteObject, "f").subtype || __classPrivateFieldGet(this, _JSHandle_remoteObject, "f").type; return 'JSHandle@' + type; } /** * Provides access to the * [Protocol.Runtime.RemoteObject](https://chromedevtools.github.io/devtools-protocol/tot/Runtime/#type-RemoteObject) * backing this handle. */ remoteObject() { return __classPrivateFieldGet(this, _JSHandle_remoteObject, "f"); } } _JSHandle_disposed = new WeakMap(), _JSHandle_context = new WeakMap(), _JSHandle_remoteObject = new WeakMap(); //# sourceMappingURL=JSHandle.js.map