Bk-rabbitmq-rpc NPM

bk-rabbitmq-rpc

This is a very opinionated abstraction over amqplib to help simplify the implementation of RPC messaging patterns on RabbitMQ.

!IMPORTANT! - bk-rabbitmq-rpc needs nodejs >= 8.x.

Features:

Creation of RPC services (client & server)
Attempt to gracefully handle lost connections and channels
Connections have a backoff policy of exponential delay randomized: ~1s, ~2s, ~4s, ~8s then stable at ~8s, ~8s...

Installation

npm install bk-rabbitmq-rpc

Getting started

On RPC server :

const RabbitmqRPC = require('bk-rabbitmq-rpc');

const client = new RabbitmqRPC();

// create a your first service
const service = client.createService('myFirstService',{ autoStartConsume: true })

// handle a service method on rpc server
service.handle('myMethod', function(data){
	return data;
});

// or if you don't use option autoStartConsume for rpc server
service.startConsume();

On RPC Client :

const RabbitmqRPC = require('bk-rabbitmq-rpc');

const client = new RabbitmqRPC();

// on rpc client ask the service method
client.request('myFirstService','myMethod',data).then((result) => {
	console.log(result);
})

API Reference

new RabbitmqRPC(options)

Return a new RabbitmqRPC client. options are :

`url` : URL to connect to RabbitMQ (default : `amqp://guest:guest@localhost:5672/`)

logLevel : Log level (default : info)
logName : Log name for Bunyan = (default : RabbitmqRPC)
exchangeName : Exchange name for handle RPC request (default : RabbitmqRPC)
log : Custom log instance (require to implement function trace, debug, info, warn and error)
responseQueue : If true, the responseQueue will be generated, it's possible to use a string to define. Use false for no responseQueue (default : true)
timeout : Timeout for rpc request in ms (default : 10000)

{client} request(serviceName, method, data, options)

Request a method on a service.

serviceName string for the service name.
method is the method name, you have to use alphanum string for the method name.
data is the data send to the client.
options options for the request with the following properties : * timeout : specify timeout for rpc request in ms. Defautlt is the time specify in the constructor. This function return a Promise.

{client} apply(serviceName, method, data, options)

Request a method on a service but without response.

serviceName string for the service name.
method is the method name, you have to use alphanum string for the method name.
data is the data send to the client.
options options for the request with the following properties : * timeout : specify timeout for rpc request in ms. Warning : defautlt is no timeout !

This function return a Promise.

{client} createService(serviceName, options)

Return a service object

serviceName string for the service name.
options are : autoStartConsume : If the service start to consume RPC message at the beginning (default : false) limit : Concurent limit request for the service. By default there is no limit.

{service} handle(method,function(data) {})

Handle a method for the service.

method is the method name, you have to use alphanum string for the method name.
function is the function called. It can be a function or a promise. The return of the function is return to the client. The function take one arg whose is the data send by the client.

!IMPORTANT! - if you don't use the option autoStartConsume: true on service constructor don't forget to call service.startConsume() to handle the RabbitmqRPC message.

Contributing

First off, thanks for your interest and for wanting to contribute!

Run tests

# With docker
npm run build-image #to build rabbitmq Image
npm run start-image #to start rabbitmq on localhost
# Or provide your own local rabbitmq install

# run tests
npm test

# run lint
npm run lint

# run coverage
npm run coverage