An event emitter that uses MongoDB capped collections.

Usage no npm install needed!

<script type="module">
  import sealMongoNotification from '';



CircleCI AppVeyor

An event emitter and receiver that uses MongoDB capped collections.


$ npm install seal-mongo-notification

Quick start

First you need to add a reference to seal-mongo-notification to your application.

const mongoNotification = require('seal-mongo-notification');

Then connect to a MongoDB by calling the function mongoNotification. Provide an options object and a callback:

  url: 'mongodb://...',
  topic: 'messages',
  writeOnly: false
}, (err, notification) => {
  // ...

The options contain:

  • url mandatory, a connection string,
  • topic mandatory, the name of a topic collection
  • writeOnly optional, the open mode, default: false

Emit events

Call the emit function for actually emitting an event:

notification.emit('foo', { foo: 'bar' });

Optionally you may specify a callback to get notified when the event has been persisted:

notification.emit('foo', { foo: 'bar' }, (err) => {
  // ...

Receive events

If you want to receive events send by your application use the on function:

notification.on('foo', (payload) => {
  // ...

Write only mode

If you only want to emit events but not receive any you can set the writeOnly option to true when connecting.

  writeOnly: true
}, (err, notification) => {
  // ...

Running the build

To build this module use roboter.

$ bot