# amqp-helper

> A Node.js helper for AMQP messaging.

Latest version **1.0.0** (published 2019-01-15) · ISC license · 0 weekly downloads

## Install

```sh
npm install amqp-helper
pnpm add amqp-helper
yarn add amqp-helper
bun add amqp-helper
```

## Health

**Score 15/100 (F)** — status: abandoned.

Positive: no vulnerabilities.

Warnings: low downloads; no types; no esm support.

Negative: abandoned; low maintenance score.

## Facts

| | |
|---|---|
| Version | 1.0.0 |
| Published | 2019-01-15 |
| First published | 2017-03-22 |
| Weekly downloads | 0 |
| License | ISC |
| TypeScript types | none |
| Module format | CommonJS |
| Dependencies | 1 |
| Unpacked size | 9.2 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| Maintainers | a.carbone |

## Links

- npm: https://www.npmjs.com/package/amqp-helper
- npm.io page: https://npm.io/package/amqp-helper

## Dependencies (1)

- [amqplib](https://npm.io/package/amqplib.md) ^0.5.2

## Recent versions

- 1.0.0 (latest) — 2019-01-15
- 0.0.1-security — 2017-03-22

## README

# amqp-helper

A Node.js helper for AMQP messaging.

## Installation

Still to be published on NPM.

## Requirements

The library works by pushing and retrieving messages from the message broker identified by the environment variable `MESSAGE_BROKER`.
`MESSAGE_BROKER` can be whatever you use to identify the message broker host (IP address or hostname).
The optional environment variables `RABBITMQ_USER` and `RABBITMQ_PASS` are used to authenticate to the `MESSAGE_BROKER`.
Docker Secrets are supported for storing `RABBITMQ_USER` and `RABBITMQ_PASS`;

If you're using docker, it's enough to define the env variables into the docker-compose.yml:
```
  environment:
    - MESSAGE_BROKER=rabbitmq # in this case rabbitmq is the name of another container
    - RABBITMQ_USER=username
    - RABBITMQ_PASS=password
```

## Usage

The aim of the library is to ease AMQP messaging configuration and execution by:

  - removing the overhead of the AMQP connection configuration;
  - offering easy to use (and remember) functions.

### Work Queue

#### Push to a queue

```
const mq = require('amqp-helper');

mq.push({
  queue: 'basket.save',
  message: {
    products: [4, 8, 15, 16, 23, 42],
    total: 42
  }
});
```

#### Retrieve messages from a queue

```
const mq = require('amqp-helper');

mq.consume({
  queue: 'basket.save',
  callback: res => {
    console.log(res.json);
  }
});
```

### Publish/Subscribe

In this case the communication is handled by defining an exchange instead of a queue.

#### Publish a message

```
const mq = require('amqp-helper');

mq.pub({
  exchange: 'order.billing-changed',
  message: {
    data: userData
  }
});
```

#### Consume a message

Multiple consumers can subscribe to an exchange and get the same message

```
const mq = require('amqp-helper');

mq.sub({
  exchange: 'order.billing-changed',
  callback: res => {
    console.log(res);
  }
});
```

### RPC

Remote Procedure Call pattern can be easily set up by:

#### Invoking an RPC

```
const mq = require('amqp-helper');

mq.rpc({
  queue: 'user.get',
  message: {
    user_id: 3
  }
}).then(result => {
  console.log(result);
});
```

#### Listening for the RPC message

```
const mq = require('amqp-helper');

mq.consume({
  queue: 'user.get',
  callback: data => {

    // Invoking RPC callback
    data.channel.sendToQueue(
      data.message.properties.replyTo,
      Buffer.from(JSON.stringify({
        userData: {
          name: 'Douglas'
        }
      })),
      {
        correlationId: data.message.properties.correlationId
      }
    );

  }
});
```

## Todo

  - Enhance documentation
  - Code coverage

## Contribution

```
cp .env.dist .env
docker-compose up -d
./npm install
./npm test
```

---
_Source: https://npm.io/package/amqp-helper · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._