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/* eslint-disable no-restricted-globals */
import { logger } from '@rails/actioncable';
// This is based on https://github.com/rails/rails/blob/5a477890c809d4a17dc0dede43c6b8cef81d8175/actioncable/app/javascript/action_cable/connection_monitor.js
// so that we can take advantage of the improved reconnection logic. We can remove this once we upgrade @rails/actioncable to a version that includes this.
// Responsible for ensuring the cable connection is in good health by validating the heartbeat pings sent from the server, and attempting
// revival reconnections if things go astray. Internal class, not intended for direct user manipulation.
const now = () => new Date().getTime();
const secondsSince = (time) => (now() - time) / 1000;
class ConnectionMonitor {
constructor(connection) {
this.visibilityDidChange = this.visibilityDidChange.bind(this);
this.connection = connection;
this.reconnectAttempts = 0;
}
start() {
if (!this.isRunning()) {
this.startedAt = now();
delete this.stoppedAt;
this.startPolling();
addEventListener('visibilitychange', this.visibilityDidChange);
logger.log(
`ConnectionMonitor started. stale threshold = ${this.constructor.staleThreshold} s`,
);
}
}
stop() {
if (this.isRunning()) {
this.stoppedAt = now();
this.stopPolling();
removeEventListener('visibilitychange', this.visibilityDidChange);
logger.log('ConnectionMonitor stopped');
}
}
isRunning() {
return this.startedAt && !this.stoppedAt;
}
recordPing() {
this.pingedAt = now();
}
recordConnect() {
this.reconnectAttempts = 0;
this.recordPing();
delete this.disconnectedAt;
logger.log('ConnectionMonitor recorded connect');
}
recordDisconnect() {
this.disconnectedAt = now();
logger.log('ConnectionMonitor recorded disconnect');
}
// Private
startPolling() {
this.stopPolling();
this.poll();
}
stopPolling() {
clearTimeout(this.pollTimeout);
}
poll() {
this.pollTimeout = setTimeout(() => {
this.reconnectIfStale();
this.poll();
}, this.getPollInterval());
}
getPollInterval() {
const { staleThreshold, reconnectionBackoffRate } = this.constructor;
const backoff = (1 + reconnectionBackoffRate) ** Math.min(this.reconnectAttempts, 10);
const jitterMax = this.reconnectAttempts === 0 ? 1.0 : reconnectionBackoffRate;
const jitter = jitterMax * Math.random();
return staleThreshold * 1000 * backoff * (1 + jitter);
}
reconnectIfStale() {
if (this.connectionIsStale()) {
logger.log(
`ConnectionMonitor detected stale connection. reconnectAttempts = ${
this.reconnectAttempts
}, time stale = ${secondsSince(this.refreshedAt)} s, stale threshold = ${
this.constructor.staleThreshold
} s`,
);
this.reconnectAttempts += 1;
if (this.disconnectedRecently()) {
logger.log(
`ConnectionMonitor skipping reopening recent disconnect. time disconnected = ${secondsSince(
this.disconnectedAt,
)} s`,
);
} else {
logger.log('ConnectionMonitor reopening');
this.connection.reopen();
}
}
}
get refreshedAt() {
return this.pingedAt ? this.pingedAt : this.startedAt;
}
connectionIsStale() {
return secondsSince(this.refreshedAt) > this.constructor.staleThreshold;
}
disconnectedRecently() {
return (
this.disconnectedAt && secondsSince(this.disconnectedAt) < this.constructor.staleThreshold
);
}
visibilityDidChange() {
if (document.visibilityState === 'visible') {
setTimeout(() => {
if (this.connectionIsStale() || !this.connection.isOpen()) {
logger.log(
`ConnectionMonitor reopening stale connection on visibilitychange. visibilityState = ${document.visibilityState}`,
);
this.connection.reopen();
}
}, 200);
}
}
}
ConnectionMonitor.staleThreshold = 6; // Server::Connections::BEAT_INTERVAL * 2 (missed two pings)
ConnectionMonitor.reconnectionBackoffRate = 0.15;
export default ConnectionMonitor;
|
