HoSCom

Communication module for HoS services.

npm install hos-com

requirement:

• rabbitMQ

Example

Each service in HoS environment need to have a contract suitable to its needs, please find the example of a contract in test/serviceContract

In HoS we love swagger. before developing your service you need to write your documentation ether in swagger or other tools like API bluepring and convert it to swagger JSON and includes it in your service contract, note that other service will send messages to each other base on basePath they should start with /, which in each service should be unique, tasks are in paths and also should start with /.

Creating an instance of the service:

serviceContract = require('./serviceContract')
HoSCom = require('hos-com')
 
HoSService = new HosCom serviceContract
HoSService.connect()

In order to give the library access to the target rabbitMQ you can set following environmental variables:

• AMQP_URL
• AMQP_USERNAME
• AMQP_PASSWORD

or when initializing the service pass as input argument: HoSService = new HosCom serviceContract, amqpurl, username, password

connect() return a promise for getting connected into HoS environment. after initialization you can send message to other services:

ok = HoSService.sendMessage {foo: "1"} , "/ServiceName", {task: '/TaskName', method: 'method'}

by default by sending message HoSCom will assume you expect to get a response back in case you do not need a reply you can specify by passing false as the last argument of sendMessage, sendMessage returns a promise which contain the reply message if successful and error in catch if the request failed

ok.then (replyJSON)=>
    console.log replyJSON
ok.catch (error)=>
    console.log error

and according to your service contract HoSCom will emit the incoming message events:

HoSService.on '/TaskName.method', (msg)=>

A message should be replied or rejected, ether with content or without content(in which case the reply won't be send to requester but just allows the HoSCom to acknowledge the message and free service queue in rabbitMQ)

msg.content.foo = msg.content.foo + 1
msg.reply(msg.content)

message can be rejected msg.reject('internal issue', 501) default value for error code is 500.

Note: for using the current package you have to have a running HoSAuth service to authenticate validation of the packages, for more info please refer to HoSAuth

Running Tests

Run test by:

gulp test

requires local rabbitMQ or setting up AMQP_URL , AMQP_USERNAME and AMQP_PASSWORD

This software is licensed under the MIT License.