amqp-1.0-client

Node AMQP 1.0 Client Module

Introduction

A module for connecting to AMQP 1.0 messaging queues such as AWS MQ. Allows for unicast/broadcast messages and leader election if multiple clients are connected.

Setup

Installing the Module

npm install --save amqp-1.0-client

Enviroment Variables

None of the below fiels are strictly required and will revert to default if not set. Please note that depending on your setup the defaults may or may not work.

Name	Description	Required	Default	Options
AMQP_HOST	Hostname of the AMQP endpoint.	false	localhost	/
AMQP_PORT	Port of the AMQP endpoint.	false	5672	5672/5671 (ssl)
AMQP_PROTO	Protocol used by the AMQP endpoint.	false	amqp	amqp/amqps (ssl)
AMQP_USERNAME	Username for secure connections.	false	admin	/
AMQP_PASSWORD	Password for secure connections.	false	admin	/
AMQP_CLIENT_POLL_INTERVAL	Update frquency used to publish/check for cluster clients	false	10(seconds)	10 to 60 (recommended)
AMQP_CLIENT_EXPIRE_LIMIT	Known clients list, set the maximum time before deleting them since they are last seen.	false	30	30 to 120 (recommended)
AMQP_MESSAGE_SEND_INTERVAL	Interval to send messages (recommended to be short).	false	1	1 to 60 (recommended)
AMPQ_DEBUG_ENABLED	If set to true, debug messages for the AMQP client will be printed.	false	false	/

Usage

Below are a few simple examples on how to use this module. It's intended to simplify the process of sending ad processing messages.

// Initialize the module.
const amqp = require("amqp-1.0-client");

// Connect to a queue and assign action to new messages.
amqp.connect("MY_QUEUE", process_task);

var list_of_tasks = [
    "one",
    "two",
    "three"
];

// On ready send a broadcast message and single message to a random endpoint.
amqp.on("ready", () => {
    amqp.broadcast("This is a broadcast");
    amqp.send("This is a unicast message!");

    // If this is the leader then sed out tasks to everyone.
    if (amqp.leader) {
        for (var task of list_of_tasks){
            amqp.send({
                "task": task,
                "some_lbl": "some value"
            });
        }
    }
});

// Perform an action when a message is received. Note that the internal stricture of the "message" variable is entirely at your discression.
const process_task = (message) => {
    console.log(`Task received: ${message.task}`)
}

// Do something if the leader changes.
amqp.on("leader_change", () => {
    console.log("All hail the new leader!");
});

To-Do

• Add method for setting module variables using a module function or variables rather than enviroment variables.
• Add support for amqp 0.9.
• Suggestions? Submit an issue on the project page on GitLab!