I am trying to make a simple server that use google oauth (without express and passportjs, as I want to study the data exchanged).

When my program attempts to send a post request to google, nodejs throws:

http.js:593 throw new TypeError('first argument must be a string or Buffer');

I have checked and make sure that all parameters in query and option are all string, but the error still persist. What could I have missed here?

Here is my code:

// Load the http module to create an http server.

var http = require('http');

var url = require('url');

var fs = require('fs');

var querystring = require('querystring');

var content;



fs.readFile('./test.html',function(err,data){

    content = data;

});



// Configure our HTTP server to respond with Hello World to all requests.

var server = http.createServer(function (request, response) {

  response.writeHead(200, {Content-Type: text/html});

  var path = url.parse(request.url).pathname;

  var query = querystring.parse(url.parse(request.url).query);

  var code;

  if (query!=null) {

    code = query.code;

  };



  if ('/auth/google/callback'==path){



    var data = querystring.stringify({

        'code':          ''+code,

        'client_id':     'id',

        'client_secret': 'secret',

        'redirect_uri':  'http://localhost:8999/auth/google/code/callback',

        'grant_type':    'authorization_code'

    });



    var options = {

        hostname: 'accounts.google.com',

        port:'80',

        path: '/o/oauth2/token',

        method: 'POST',

        headers: {

          'Content-Type': 'application/x-www-form-urlencoded',

          'Content-Length': ''+data.length

      }

    };



    debugger;

    var post = http.request(options, function(res){

        response.write(res);

        response.end();

    });

    debugger;

    post.write(data);

    debugger;

    post.end();

  }



  else if (path=='/auth/google/code/callback'){

    console.log(request.headers);

    console.log(request.url);

  }



  else response.end(content);



  console.log(request.headers);

  console.log(request.url);

});



// Listen on port 8000, IP defaults to 127.0.0.1

server.listen(8999);



// Put a friendly message on the terminal

console.log(Server running at http://127.0.0.1:8000/);

Many thanks,