diff options
Diffstat (limited to 'actioncable/app/javascript/action_cable/connection.js')
-rw-r--r-- | actioncable/app/javascript/action_cable/connection.js | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/actioncable/app/javascript/action_cable/connection.js b/actioncable/app/javascript/action_cable/connection.js new file mode 100644 index 0000000000..b2910cb2a6 --- /dev/null +++ b/actioncable/app/javascript/action_cable/connection.js @@ -0,0 +1,161 @@ +import adapters from "./adapters" +import ConnectionMonitor from "./connection_monitor" +import INTERNAL from "./internal" +import logger from "./logger" + +// Encapsulate the cable connection held by the consumer. This is an internal class not intended for direct user manipulation. + +const {message_types, protocols} = INTERNAL +const supportedProtocols = protocols.slice(0, protocols.length - 1) + +const indexOf = [].indexOf + +class Connection { + constructor(consumer) { + this.open = this.open.bind(this) + this.consumer = consumer + this.subscriptions = this.consumer.subscriptions + this.monitor = new ConnectionMonitor(this) + this.disconnected = true + } + + send(data) { + if (this.isOpen()) { + this.webSocket.send(JSON.stringify(data)) + return true + } else { + return false + } + } + + open() { + if (this.isActive()) { + logger.log(`Attempted to open WebSocket, but existing socket is ${this.getState()}`) + return false + } else { + logger.log(`Opening WebSocket, current state is ${this.getState()}, subprotocols: ${protocols}`) + if (this.webSocket) { this.uninstallEventHandlers() } + this.webSocket = new adapters.WebSocket(this.consumer.url, protocols) + this.installEventHandlers() + this.monitor.start() + return true + } + } + + close({allowReconnect} = {allowReconnect: true}) { + if (!allowReconnect) { this.monitor.stop() } + if (this.isActive()) { return (this.webSocket ? this.webSocket.close() : undefined) } + } + + reopen() { + logger.log(`Reopening WebSocket, current state is ${this.getState()}`) + if (this.isActive()) { + try { + return this.close() + } catch (error) { + logger.log("Failed to reopen WebSocket", error) + } + finally { + logger.log(`Reopening WebSocket in ${this.constructor.reopenDelay}ms`) + setTimeout(this.open, this.constructor.reopenDelay) + } + } else { + return this.open() + } + } + + getProtocol() { + return (this.webSocket ? this.webSocket.protocol : undefined) + } + + isOpen() { + return this.isState("open") + } + + isActive() { + return this.isState("open", "connecting") + } + + // Private + + isProtocolSupported() { + return indexOf.call(supportedProtocols, this.getProtocol()) >= 0 + } + + isState(...states) { + return indexOf.call(states, this.getState()) >= 0 + } + + getState() { + if (this.webSocket) { + for (let state in adapters.WebSocket) { + if (adapters.WebSocket[state] === this.webSocket.readyState) { + return state.toLowerCase() + } + } + } + return null + } + + installEventHandlers() { + for (let eventName in this.events) { + const handler = this.events[eventName].bind(this) + this.webSocket[`on${eventName}`] = handler + } + } + + uninstallEventHandlers() { + for (let eventName in this.events) { + this.webSocket[`on${eventName}`] = function() {} + } + } + +} + +Connection.reopenDelay = 500 + +Connection.prototype.events = { + message(event) { + if (!this.isProtocolSupported()) { return } + const {identifier, message, reason, reconnect, type} = JSON.parse(event.data) + switch (type) { + case message_types.welcome: + this.monitor.recordConnect() + return this.subscriptions.reload() + case message_types.disconnect: + logger.log(`Disconnecting. Reason: ${reason}`) + return this.close({allowReconnect: reconnect}) + case message_types.ping: + return this.monitor.recordPing() + case message_types.confirmation: + return this.subscriptions.notify(identifier, "connected") + case message_types.rejection: + return this.subscriptions.reject(identifier) + default: + return this.subscriptions.notify(identifier, "received", message) + } + }, + + open() { + logger.log(`WebSocket onopen event, using '${this.getProtocol()}' subprotocol`) + this.disconnected = false + if (!this.isProtocolSupported()) { + logger.log("Protocol is unsupported. Stopping monitor and disconnecting.") + return this.close({allowReconnect: false}) + } + }, + + close(event) { + logger.log("WebSocket onclose event") + if (this.disconnected) { return } + this.disconnected = true + this.monitor.recordDisconnect() + return this.subscriptions.notifyAll("disconnected", {willAttemptReconnect: this.monitor.isRunning()}) + }, + + error() { + logger.log("WebSocket onerror event") + } +} + +export default Connection |