puppeteer/lib/Connection.js
Andrey Lushnikov e8a085ccfb
feat(appMode): support pipes for appMode (#2032)
This patch starts using pipes as a transport to
the browser instance instead of websocket.
2018-02-14 17:51:29 -08:00

243 lines
7.3 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 {helper} = require('./helper');
const debugProtocol = require('debug')('puppeteer:protocol');
const debugSession = require('debug')('puppeteer:session');
const EventEmitter = require('events');
const WebSocket = require('ws');
const Pipe = require('./Pipe');
class Connection extends EventEmitter {
/**
* @param {string} url
* @param {number=} delay
* @return {!Promise<!Connection>}
*/
static async createForWebSocket(url, delay = 0) {
return new Promise((resolve, reject) => {
const ws = new WebSocket(url, { perMessageDeflate: false });
ws.on('open', () => resolve(new Connection(url, ws, delay)));
ws.on('error', reject);
});
}
/**
* @param {!NodeJS.WritableStream} pipeWrite
* @param {!NodeJS.ReadableStream} pipeRead
* @param {number=} delay
* @return {!Connection}
*/
static createForPipe(pipeWrite, pipeRead, delay = 0) {
return new Connection('', new Pipe(pipeWrite, pipeRead), delay);
}
/**
* @param {string} url
* @param {!Puppeteer.ConnectionTransport} transport
* @param {number=} delay
*/
constructor(url, transport, delay = 0) {
super();
this._url = url;
this._lastId = 0;
/** @type {!Map<number, {resolve: function, reject: function, error: !Error, method: string}>}*/
this._callbacks = new Map();
this._delay = delay;
this._transport = transport;
this._transport.on('message', this._onMessage.bind(this));
this._transport.on('close', this._onClose.bind(this));
/** @type {!Map<string, !CDPSession>}*/
this._sessions = new Map();
}
/**
* @return {string}
*/
url() {
return this._url;
}
/**
* @param {string} method
* @param {!Object=} params
* @return {!Promise<?Object>}
*/
send(method, params = {}) {
const id = ++this._lastId;
const message = JSON.stringify({id, method, params});
debugProtocol('SEND ► ' + message);
this._transport.send(message);
return new Promise((resolve, reject) => {
this._callbacks.set(id, {resolve, reject, error: new Error(), method});
});
}
/**
* @param {function()} callback
*/
setClosedCallback(callback) {
this._closeCallback = callback;
}
/**
* @param {string} message
*/
async _onMessage(message) {
if (this._delay)
await new Promise(f => setTimeout(f, this._delay));
debugProtocol('◀ RECV ' + message);
const object = JSON.parse(message);
if (object.id && this._callbacks.has(object.id)) {
const callback = this._callbacks.get(object.id);
this._callbacks.delete(object.id);
if (object.error)
callback.reject(rewriteError(callback.error, `Protocol error (${callback.method}): ${object.error.message} ${object.error.data}`));
else
callback.resolve(object.result);
} else {
console.assert(!object.id);
if (object.method === 'Target.receivedMessageFromTarget') {
const session = this._sessions.get(object.params.sessionId);
if (session)
session._onMessage(object.params.message);
} else if (object.method === 'Target.detachedFromTarget') {
const session = this._sessions.get(object.params.sessionId);
if (session)
session._onClosed();
this._sessions.delete(object.params.sessionId);
} else {
this.emit(object.method, object.params);
}
}
}
_onClose() {
if (this._closeCallback) {
this._closeCallback();
this._closeCallback = null;
}
this._transport.removeAllListeners();
for (const callback of this._callbacks.values())
callback.reject(rewriteError(callback.error, `Protocol error (${callback.method}): Target closed.`));
this._callbacks.clear();
for (const session of this._sessions.values())
session._onClosed();
this._sessions.clear();
}
dispose() {
this._onClose();
this._transport.close();
}
/**
* @param {string} targetId
* @return {!Promise<!CDPSession>}
*/
async createSession(targetId) {
const {sessionId} = await this.send('Target.attachToTarget', {targetId});
const session = new CDPSession(this, targetId, sessionId);
this._sessions.set(sessionId, session);
return session;
}
}
class CDPSession extends EventEmitter {
/**
* @param {!Connection} connection
* @param {string} targetId
* @param {string} sessionId
*/
constructor(connection, targetId, sessionId) {
super();
this._lastId = 0;
/** @type {!Map<number, {resolve: function, reject: function, error: !Error, method: string}>}*/
this._callbacks = new Map();
this._connection = connection;
this._targetId = targetId;
this._sessionId = sessionId;
}
/**
* @param {string} method
* @param {!Object=} params
* @return {!Promise<?Object>}
*/
send(method, params = {}) {
if (!this._connection)
return Promise.reject(new Error(`Protocol error (${method}): Session closed. Most likely the page has been closed.`));
const id = ++this._lastId;
const message = JSON.stringify({id, method, params});
debugSession('SEND ► ' + message);
this._connection.send('Target.sendMessageToTarget', {sessionId: this._sessionId, message}).catch(e => {
// The response from target might have been already dispatched.
if (!this._callbacks.has(id))
return;
const callback = this._callbacks.get(id);
this._callbacks.delete(id);
callback.reject(rewriteError(callback.error, e && e.message));
});
return new Promise((resolve, reject) => {
this._callbacks.set(id, {resolve, reject, error: new Error(), method});
});
}
/**
* @param {string} message
*/
_onMessage(message) {
debugSession('◀ RECV ' + message);
const object = JSON.parse(message);
if (object.id && this._callbacks.has(object.id)) {
const callback = this._callbacks.get(object.id);
this._callbacks.delete(object.id);
if (object.error)
callback.reject(rewriteError(callback.error, `Protocol error (${callback.method}): ${object.error.message} ${object.error.data}`));
else
callback.resolve(object.result);
} else {
console.assert(!object.id);
this.emit(object.method, object.params);
}
}
async detach() {
await this._connection.send('Target.detachFromTarget', {sessionId: this._sessionId});
}
_onClosed() {
for (const callback of this._callbacks.values())
callback.reject(rewriteError(callback.error, `Protocol error (${callback.method}): Target closed.`));
this._callbacks.clear();
this._connection = null;
}
}
helper.tracePublicAPI(CDPSession);
/**
* @param {!Error} error
* @param {string} message
* @return {!Error}
*/
function rewriteError(error, message) {
error.message = message;
return error;
}
module.exports = {Connection, CDPSession};