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Diffstat (limited to 'ext/mixed/js/comm.js')
| -rw-r--r-- | ext/mixed/js/comm.js | 282 |
1 files changed, 282 insertions, 0 deletions
diff --git a/ext/mixed/js/comm.js b/ext/mixed/js/comm.js new file mode 100644 index 00000000..7787616e --- /dev/null +++ b/ext/mixed/js/comm.js @@ -0,0 +1,282 @@ +/* + * Copyright (C) 2020 Yomichan Authors + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <https://www.gnu.org/licenses/>. + */ + +class CrossFrameAPIPort extends EventDispatcher { + constructor(otherFrameId, port, messageHandlers) { + super(); + this._otherFrameId = otherFrameId; + this._port = port; + this._messageHandlers = messageHandlers; + this._activeInvocations = new Map(); + this._invocationId = 0; + this._eventListeners = new EventListenerCollection(); + } + + get otherFrameId() { + return this._otherFrameId; + } + + prepare() { + this._eventListeners.addListener(this._port.onDisconnect, this._onDisconnect.bind(this)); + this._eventListeners.addListener(this._port.onMessage, this._onMessage.bind(this)); + } + + invoke(action, params, ackTimeout, responseTimeout) { + return new Promise((resolve, reject) => { + if (this._port === null) { + reject(new Error('Port is disconnected')); + return; + } + + const id = this._invocationId++; + const invocation = {id, resolve, reject, responseTimeout, ack: false, timer: null}; + this._activeInvocations.set(id, invocation); + + if (ackTimeout !== null) { + try { + invocation.timer = setTimeout(() => this._onError(id, new Error('Timeout (ack)')), ackTimeout); + } catch (e) { + this._onError(id, new Error('Failed to set timeout')); + return; + } + } + + try { + this._port.postMessage({type: 'invoke', id, data: {action, params}}); + } catch (e) { + this._onError(id, e); + } + }); + } + + disconnect() { + this._onDisconnect(); + } + + // Private + + _onDisconnect() { + if (this._port === null) { return; } + this._eventListeners.removeAllEventListeners(); + this._port = null; + for (const id of this._activeInvocations.keys()) { + this._onError(id, new Error('Disconnected')); + } + this.trigger('disconnect', this); + } + + _onMessage({type, id, data}) { + switch (type) { + case 'invoke': + this._onInvoke(id, data); + break; + case 'ack': + this._onAck(id); + break; + case 'result': + this._onResult(id, data); + break; + } + } + + // Response handlers + + _onAck(id) { + const invocation = this._activeInvocations.get(id); + if (typeof invocation === 'undefined') { + yomichan.logWarning(new Error(`Request ${id} not found for ack`)); + return; + } + + if (invocation.ack) { + this._onError(id, new Error(`Request ${id} already ack'd`)); + return; + } + + invocation.ack = true; + + if (invocation.timer !== null) { + clearTimeout(invocation.timer); + invocation.timer = null; + } + + const responseTimeout = invocation.responseTimeout; + if (responseTimeout !== null) { + try { + invocation.timer = setTimeout(() => this._onError(id, new Error('Timeout (response)')), responseTimeout); + } catch (e) { + this._onError(id, new Error('Failed to set timeout')); + } + } + } + + _onResult(id, data) { + const invocation = this._activeInvocations.get(id); + if (typeof invocation === 'undefined') { + yomichan.logWarning(new Error(`Request ${id} not found`)); + return; + } + + if (!invocation.ack) { + this._onError(id, new Error(`Request ${id} not ack'd`)); + return; + } + + this._activeInvocations.delete(id); + + if (invocation.timer !== null) { + clearTimeout(invocation.timer); + invocation.timer = null; + } + + const error = data.error; + if (typeof error !== 'undefined') { + invocation.reject(jsonToError(error)); + } else { + invocation.resolve(data.result); + } + } + + _onError(id, error) { + const invocation = this._activeInvocations.get(id); + if (typeof invocation === 'undefined') { return; } + + this._activeInvocations.delete(id); + if (invocation.timer !== null) { + clearTimeout(invocation.timer); + invocation.timer = null; + } + invocation.reject(error); + } + + // Invocation + + _onInvoke(id, {action, params}) { + const messageHandler = this._messageHandlers.get(action); + if (typeof messageHandler === 'undefined') { + this._sendError(id, new Error(`Unknown action: ${action}`)); + return; + } + + const {handler, async} = messageHandler; + + this._sendAck(id); + if (async) { + this._invokeHandlerAsync(id, handler, params); + } else { + this._invokeHandler(id, handler, params); + } + } + + _invokeHandler(id, handler, params) { + try { + const result = handler(params); + this._sendResult(id, result); + } catch (error) { + this._sendError(id, error); + } + } + + async _invokeHandlerAsync(id, handler, params) { + try { + const result = await handler(params); + this._sendResult(id, result); + } catch (error) { + this._sendError(id, error); + } + } + + _sendResponse(data) { + if (this._port === null) { return; } + try { + this._port.postMessage(data); + } catch (e) { + // NOP + } + } + + _sendAck(id) { + this._sendResponse({type: 'ack', id}); + } + + _sendResult(id, result) { + this._sendResponse({type: 'result', id, data: {result}}); + } + + _sendError(id, error) { + this._sendResponse({type: 'result', id, data: {error: errorToJson(error)}}); + } +} + +class CrossFrameAPI { + constructor() { + this._ackTimeout = 3000; // 3 seconds + this._responseTimeout = 10000; // 10 seconds + this._commPorts = new Map(); + this._messageHandlers = new Map(); + this._onDisconnectBind = this._onDisconnect.bind(this); + } + + prepare() { + chrome.runtime.onConnect.addListener(this._onConnect.bind(this)); + } + + async invoke(targetFrameId, action, params={}) { + const commPort = this._getOrCreateCommPort(targetFrameId); + return await commPort.invoke(action, params, this._ackTimeout, this._responseTimeout); + } + + registerHandlers(messageHandlers) { + for (const [key, value] of messageHandlers) { + if (this._messageHandlers.has(key)) { + throw new Error(`Handler ${key} is already registered`); + } + this._messageHandlers.set(key, value); + } + } + + _onConnect(port) { + const match = /^cross-frame-communication-port-(\d+)$/.exec(`${port.name}`); + if (match === null) { return; } + + const otherFrameId = parseInt(match[1], 10); + this._setupCommPort(otherFrameId, port); + } + + _onDisconnect(commPort) { + commPort.off('disconnect', this._onDisconnectBind); + this._commPorts.delete(commPort.otherFrameId); + } + + _getOrCreateCommPort(otherFrameId) { + const commPort = this._commPorts.get(otherFrameId); + return (typeof commPort !== 'undefined' ? commPort : this._createCommPort(otherFrameId)); + } + + _createCommPort(otherFrameId) { + const port = chrome.runtime.connect(null, {name: `background-cross-frame-communication-port-${otherFrameId}`}); + return this._setupCommPort(otherFrameId, port); + } + + _setupCommPort(otherFrameId, port) { + const commPort = new CrossFrameAPIPort(otherFrameId, port, this._messageHandlers); + this._commPorts.set(otherFrameId, commPort); + commPort.prepare(); + commPort.on('disconnect', this._onDisconnectBind); + return commPort; + } +} |