/choo-sse

Small wrapper around server-sent event browser API, for choo apps

Primary LanguageJavaScriptMIT LicenseMIT

choo-sse stability

npm version build status downloads js-standard-style

Small wrapper around server-sent event browser API, for choo apps

Usage

var choo = require('choo')
var html = require('choo/html')

var app = choo()
app.use(require('choo-sse')('/sse'))
app.use(live)
app.route('/', mainView)
app.mount('body')

function mainView (state, emit) {
  return html`
    <body>
      <h2>Counter example</h2>
      <h3>Numbers are sent by the server</h3>
      <span id="counter"></span>
    </body>
  `
}

function live (state, emitter) {
  emitter.on('DOMContentLoaded', function () {
    emitter.on('sse:message', (data, event) => {
      var msgElement = document.getElementById('counter')
      msgElement.textContent = data
    })
    emitter.on('sse:error', err => {
      emitter.emit('log:error', err)
    })
  })
}

Events

sse:error | sse.events.ERROR

Emitted if the Event Source constructor or any of its methods throws an exception.

sse:open | sse.events.OPEN

Emitted when the connection is established with the server.

sse:close | sse.events.CLOSE

Emitted when the connection is closed.

sse:message | sse.events.MESSAGE

Listen to this event to get messages from the server.

API

plugin = sse([route], [opts])

The plugin accepts two parameters. You must pass the route for the Event Source object. Also you can pass some options as a second argument.

  • withCredentials: Boolean. Indicate if CORS should be set to include credentials. Defaults to false.

If the object is correctly created, then you have an object in the state of your app with the following properties:

  • state: A string describing the state of the connection, can be CONNECTING, OPEN or CLOSED .
  • url: A string with the url of the source.
  • withCredentials: A boolean indicating if the Event Source object was instantiated with CORS credentials.

See Also

  • choo-websockets - Small wrapper around WebSocket browser API, for choo apps

License

MIT