xenops

Node js Structured Framework

This framework is REST API based one and it can be used for fast api development. User can easily develop api functionality without doing much work.
Framework structure is shown in fig.

Framework structure

The structure of the files in an application is very important.It will help us to expand the current application structure by adding more modules and make an good app.

Before doing that one , we should clearly understand the basic structure and how to make simple api function using current app. We will separate core functions of our app into sensible and efficient file structure.

This framework contains some important modules,

• Configuration
• Routing
• Logging
• Socket io programming
• Data management
• Client testing

Configuration

This is the main configuration file (config/config.js) that contains all configurations needed for the entire application to work. DB config, server config, app config, socket config etc.

Routing

Restify server based routing configuration implemented.The file routes/routes.js file exports the Router object that handles all the route to application framework.

Server

Node Restify server is used for framework development. server.js file is used to configure server, socket, and handlers.Once everything is configured correctly, you need to call initApp() function that will start application. There is one index file in the root folder and it is entry point of application and db connection, server initialisation start from here.This file will invoke the framework server and start application.

Just need to run node index.js (Development or production mode can set by using NODE_ENV)
and you can see that server is started. Open the browser and type url :http://localhost:8888/ Gives : "Welcome to REST API service --- \n"

Data management

This framework has separate directory structure for each file model, controller etc. Router routes the url to one function inside the controller. This framework structure contains controllers, models etc. Controller navigate through the application and handlers (functions) inside controller call the appropriate model and returns the data. Data is taken from models, models retrieves the data from database, for different database we have to use different node database modules. Here we have used the sql server node database module.

Socket io programming

Socket io connection established through the same port used for api development. We have modularise the code to controller and model.There is no view present in this structured Framework.Here i am trying to explain code features of socket io programming and cool feature technology named web Real Time communication through code samples. Node.js uses an event-driven, Non blocking I/O programming model and javascript is event driven language.One of the main feature of node js is event module, and EventEmitter class.Here i am not going to explain full server side code to implement multiple room real time communication. But I beleive that you will get a basic boilerplate for creating a multiple realtime communication. In this socket io module implemented in socket controller, socket io configuration settings for the production and development are given. In the socket io programming socket has to listen for many events. We have created one custom event class to control socket events. Socket Event listeners are added in controllers. Custom socket event class will handle all events and added in controller.

// Event emitter Handler Obj 
var socketEventEmit = require('../events/socketEventEmitter');  

Views management

We have already mentioned that this framework is REST Api based one and there is no view present in it. But in future we are looking for common framework for web based and REST api. For this one, we have started static and dynamic html page rendering using current framework.

// Custom controller routes
this.server.get('/staticview', this.controllers.custom.staticView); 
this.server.get('/dynamicview', this.controllers.custom.dynamicView); 

Static and dynamic page render handlers.

Now there is no Template mechanism implemented.

Data handling in CRUD operations

Here we have already implemented a CRUD operation api functionalities using the current api framework.It includes user controller, model, routes etc.

Logging

In the current framework we are using winston log module.We can easily log the the info, error, warn and debug using this logger module. this file is stored in utils/logger.js file.In the application we can use like,

// Log information
logger.info('Application server started. ');

Two log files are created inside log folder for debug and exception log.

Client testing

This module is very important one and it can be used for REST api functional testing. Here is one html and js file, html file is used for socket io connection testing and js file one is used for testing
How to use this one ?

var client = require('./testClient/client');
// call client 
client.clientConnect();
client.getUsers();

Will output the results in console.

Create a REST api simple function using our framework

We present here a demo of single api function development using our own framework. Let’s begin.

Create your own custom controller

create /controllers/customController.js file and update the file with above code and save it.

Create custom model

Drop this bits of code in models/customModel.js.

Add custom controller to server.js

Update the server.js with code shown in above. Initialise service handlers with new custom controller object. Currently we are storing our action objects in service handlers object.

Add Url Routing

Edit routes\routes.js and update it.

Now everything is completed and the new REST api function developed using our own new structured framework. It is very simple.

Run the server steps

Go to application folder -> cd appfolder Start node server by typing - > node index.js
Open the browser and type -> http://localhost:8888/custom It is working fine. The above mentioned example is simple one. For database related method, you can check userModel.js file Here we are using the sql server database and mssql node module included here.

Moving forward

In the future we want our framework to include cool features like

• Have multiple database(mysql, sqlite etc) configs
• Views development with templates
• Secure api development