sand-amqp

sand-amqp

This package provides AMQP integration for Sand applications. It wraps @sazze/amqp.

Installation

npm install --save sand-amqp

Usage

The Publisher and Consumer classes wrap their respective objects from @sazze/amqp. They automatically handle connectivity upon instantiation, and clean disconnection on application shutdown. The ready event is raised when connectivity is established.

Publisher

To instantiate a new Publisher instance, call sand.amqp.startPublisher(config, name).

Configuration options are available here; they are defaulted by the amqp values in your application's config/amqp.js file.

If name is provided, the publisher will be available via the sand.amqp.publishers object.

In addition to the publisher options there is also autoConnect, which defaults to true and determines whether or not to auto connect on instantiation.

Consumer

To instantiate a new Consumer instance, call sand.amqp.startConsumer(config, name).

Configuration options are available here; they are defaulted by the amqp values in your application's config/amqp.js file. If a handler function is provided as an option, it is invoked when a message is received. handler may be a regular function or a generator function.

If name is provided, the consumer will be available via the sand.amqp.consumers object.

In addition to the consumer options, specific to this library there is also autoStart, which defaults to true and determines whether or not the consumer starts on instantiation. There is also runInSandContext which defaults to true. If TRUE then the handler function runs inside a sand context.

Autostarting

If autoStart is set in the configuration, sand-amqp will automatically instantiate any publisher and consumer configurations stored in the publisherDir and consumerDir directories. This is useful if you want publishers and consumers to automatically start and persist throughout the lifetime of your application.

publisherDir and consumerDir values should be relative to your Sand application path.

Example

This example Sand application will connect to the local AMQP instance and publish the string hello world to the demo exchange once per second.

config/amqp.js:

"use strict";

module.exports = {
  all: {
    amqp: {
      host: '127.0.0.1',
      port: 5672,
      user: 'guest',
      password: 'guest',
      vhost: '/',
      ssl: {
        enable: false
      }
    }
  }
};

app.js:

"use strict";

const Sand = require('sand');
const amqp = require('sand-amqp');

new Sand({ appPath: __dirname })
  .use(amqp)
  .start(function*() {
    sand.amqp.startConsumer({
      exchange: {
        name: 'demo',
        type: 'direct'
      },
      handler: (msg) => console.log(msg)
    });

    let publisher = sand.amqp.startPublisher({
      exchange: {
        name: 'demo',
        type: 'direct'
      }
    });

    setInterval(function() {
      publisher.publish('hello world');
    }, 1000);
  });

Output:

hello world
hello world
hello world

Testing

Note: A running AMQP instance is required for tests to pass. You may need to adjust test/fixtures/config/test.js for your environment.

To test, run npm test from the project root directory.

License

ISC