Nodejs

This post is just for making notes during my learning of Node.js through various courses and online material. This will be always a work in progress blog post

Node.js is an open source server side runtime environment, which is cross platform.It uses Javascript as its language

check node version node --version

Making web request in Node we can make webrequest by using inbuilt http or by using ‘request’ example : For making web request by http

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var http = require('http');
var req = http.request('http://www.google.com/finance/info?infotype=infoquoteall&q=NSE:TCS', function(response) {
    console.log(response.statusCode);
    response.pipe(process.stdout);
});
req.end();

example: Please note that there is no space between key and : while defining options

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var http = require('http');

var options = {
  host: 'www.google.com',
  port: 80,
  path: '/finance/info?infotype=infoquoteall&q=NSE:TCS',
  method: 'GET'
};

var req = http.request(options, function(response) {
    console.log(response.statusCode);
    response.pipe(process.stdout);
});
req.end();

Example: We can simply by giving GET . There is no need to close request since we are not going to send any more information to request

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var http = require('http');

var options = {
  host: 'www.google.com',
  port: 80,
  path: '/finance/info?infotype=infoquoteall&q=NSE:TCS',
  method: 'GET'
};

http.get(options, function(response) {
    console.log(response.statusCode);
    response.pipe(process.stdout);
});

Another option is

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http.get(options, function(res){
    var body = '';

    res.on('data', function(chunk){
        body += chunk;
    });

    res.on('end', function(){
        console.log("Got a response: ", body);
    });
}).on('error', function(e){
      console.log("Got an error: ", e);
});

Starting with Node.js and Express

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npm init

Above command will create a package.json. Leave details are default or change accordingly

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npm install express --save

Above will install express and also add it as dependency in package.json

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touch app.js

Above will create a app.js file. In package.json add below

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  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "start": "node app.js"
  },

Now, if we run “npm start” from command line, it will run app.js

Bower

Package manager for web/front end. It is installed with NPM and have flat package hierarchy(doesnt install dependency underneath one level) .It works similar to NPM and have Bower.json for dependency managament.

Create a .bowerrc file and have project specific settings. Now move the components from bower_component to public folder defined earlier. update .bowerrc with below

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  {
      "directory" : "public/lib"
  }

now run below

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  bower init
  \\ leave all settings as default
  bower install --save bootstrap
  \\ it will install bootstrap. It create a directory under public/lib and under that it will have bootstrap andjquery since jquery is a dependency for bootstrap

Gulp

It is a task manager for web projects. It have code based config. It is packaged base so that we can use different external packages

Mongo DB

  • Install MongoDB from website
  • mongoD is command for running server
  • mongo is command for running another terminal for interacting with mongo db
  • show dbs will show list of db
  • Install MongoDB Node.js driver using NPM ```

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