Daemon Index File

Introduction

The below shows the difference between the index file of a daemon written without the composer, and the index file of a daemon written with the composer.

Index.js

Daemon Index without the Composer

'use strict';
//require core framework
var soajs = require('soajs');

//require daemon configuration			
var config = require('./config.js');

//require daemon business logic (the model is required inside the business logic)
var BLModule = require("./lib/index");

//create a new daemon instance	
var daemon = new soajs.server.daemon(config);		

//initialize the daemon
daemon.init(function () {		

	//implement first JOB
    daemon.job("myCustomJob", function (soajs, next) {		 
		
		//call the initBLModel function ( read more below )
        initBLModel(SOAJS, function (error, BL) {
			//if error is returned stop the execution and return it
			if(error){
				return next(error);
			}

			//pass the service configuration and soajs to the business logic			
            BL.getCart(config, soajs, function (error, response) {		

				//formulate a standardized response and return it
                return next(error, response);
            });
		});
    });

	//start the daemon
    daemon.start();		
});

//function used to read the model name from the parameter provided
//load it in memory and return an instance to it
function initBLModel(soajs, cb) {

	//get the model name from the inputs arriving via the request
    var modelName = soajs.servicesConfig[process.env.SOAJS_ENV.toUpperCase()].model;		
    
	//call BLModule.init and send the model name to load the later in memory 
	//and return an instance for it via its callback
	BLModule.init(modelName, function (error, BL) {
        if (error) {
            return cb(error);
        }
		
		//otherwise return the business logic instance via the callback
        return cb(BL);  
    });
}

Daemon Indes with the Composer

"use strict";
//require the composer
var composer = require("soajs.composer");		

//call composer.deploy to deploy the daemon from its config file
composer.deploy(__dirname + "/config.js", function(error){

	//optional log message after daemon is started
    console.log( (error)? error : "Cart Service started ...");	
});

As you can see above, the difference is quite significant. The composer takes away all the code you need to write in the index by parsing and rendering the information from the config.js file only.

So what should we add in the config.js so that the composer can do all this magic ? Read More