Async Bridge

Generic promise based request/response interface. Intended for use with post-messaging.

Example

const Bridge = require('async-bridge');

const bridge = Bridge.create();

// Bind incoming event data to the bridge.
addEventListener('message', event => bridge.receiver(event.data));

// Set an emitter for outgoing data.
bridge.emitter = data => window.parent.postMessage(data, '*');

// Register a response for a named request.
bridge.respond('getRandomNumber', () => Math.random());

// Send a request with a timeout of 1s.
bridge.request('hello?', { data: '123' }, 1000).then(response => {}).catch(error => {});

// Make sure the briges are in sync on an interval.
setInterval(bridge.sync, 2000)

Syncing

If the connection to the bridge may have been lost or if requests may have been sent before the other bridge was ready, "bridge.sync(timeout)" will attempt to syncronize the state of the two bridges. This prevents requests from being dropped.

One could sync on an interval "setInterval(bridge.sync, 2000)" for robustness, or use external events to know when a resync may be necessary.