How to post data using nodejs

Post data using nodejs

This post highlights an attempt to handle the raw format of data sent in a POST request body and how one could parse it. There are packages like body-parser for Express that do this for us so this post is merely for learning purposes. I won’t suggest the use of this solution in production.

Here's an example of using node.js to make a POST request to the Google Compiler API:

// We need this to build our post string
var querystring = require('querystring');
var http = require('http');
var fs = require('fs');

function PostCode(codestring) {
  // Build the post string from an object
  var post_data = querystring.stringify({
      'compilation_level' : 'ADVANCED_OPTIMIZATIONS',
      'output_format': 'json',
      'output_info': 'compiled_code',
    'warning_level' : 'QUIET',
      'js_code' : codestring
  });

  // An object of options to indicate where to post to
  var post_options = {
      host: 'closure-compiler.appspot.com',
      port: '80',
      path: '/compile',
      method: 'POST',
      headers: 
          'Content-Type': 'application/x-www-form-urlencoded',
          'Content-Length': Buffer.byteLength(post_data)
      }
  };

  // Set up the request
  var post_req = http.request(post_options, function(res) {
      res.setEncoding('utf8');
      res.on('data', function (chunk) {
          console.log('Response: ' + chunk);
      });
  });

// post the data
  post_req.write(post_data);

This gets a lot easier if you use the request library.

var request = require('request');

request.post(

    'http://www.yoursite.com/formpage',

    { json: { key: 'value' } },

    function (error, response, body) {

        if (!error && response.statusCode == 200) {

            console.log(body)

        }

    }

);

Aside from providing a nice syntax it makes json requests easy, handles OAuth signing (for Twitter, etc.), can do multi-part forms (e.g. for uploading files) and streaming.

To install request use command npm install request

Example code:

var request = require('request')
var options = {
  method: 'post',
  body: postData, // Javascript object
  json: true, // Use,If you are sending JSON data
  url: url,
  headers: { // Specify headers, If any }
}

request(options, function (err, res, body) {
  if (err) {
    console.log('Error :', err)
    return
  }
  console.log(' Body :', body)
});

You can also use Node.js's built-in 'http' module to make request.