'use strict';
var helper = require('./helper');

Module: OAuth

Abstraction for the authentication methods of Twitter’s API.

Notice: At the moment this is depending on request‘s ability to create OAuth signatures, but in the future this should have it’s own OAuth signing with OAuth2 support.

Methods

• Constructor
• Request Token
• Access Token
• Authenticate
• Authorize

Usage

var TwitterLib = require('twitter-rest-lite'),
oauth = new TwitterLib.OAuth(var_with_keys);

api.requestToken(callback);

api.accessToken(token, verifier, callback);

api.authenticate(callback);

api.authorize(callback);

Constructor

Parameters

• uri - Object with the basic API URI’s
• opts - Object with the following params
  • consumer_key - [Required] consumer_key from Twitter
  • consumer_secret - [Required] consumer_secret from Twitter
  • callback - [Optional]

Returns

An Object with methods requestToken, accessToken, authenticate and authorize.

Code

function OAuth(uri, opts) {
  this.uri = uri;

  /* Extending `uri` with oauth URI's */
  this.uri.requestToken = 'https://api.twitter.com/oauth/request_token';
  this.uri.accessToken = 'https://api.twitter.com/oauth/access_token';
  this.uri.authenticate = 'https://api.twitter.com/oauth/authenticate';
  this.uri.authorize = 'https://api.twitter.com/oauth/authorize';

  /* checking the required arguments */
  ['consumer_key', 'consumer_secret'].forEach(function (item) {
    if (opts[item] == null)
      throw new Error('There\'s a required argument missing: ' + item);
  });

  this.opts = opts;
}

Public: get a request token

Parameters

• callback - Callback Function

Returns

Returns a callback with an Error Object as first parameter if there was (otherwise just null) and an Object with the response with the model:

{
  token: String,
  token_secret: String,
  oauth_callback_confirmed: Boolean
}

Example

oauth.requestToken(function (err, response) {
  if (err)
    throw err;

  console.log(response);
});

response.token is used by oauth.authenticate and oauth.authorize.

Code

OAuth.prototype.requestToken = function(callback) {
  var self = this;
  var request = require('request');
  var oauth = {};
  
  ['consumer_key', 'consumer_secret', 'callback'].forEach(function (e) {
    if (self.opts[e] != null)
      oauth[e] = self.opts[e];
  });

  request({
    method: 'POST',
    uri: self.uri.requestToken,
    oauth: oauth
  }, function (err, response, body) {
    if (err)
      return callback(err);

    if (response.statusCode !== 200) {
      return callback(new Error(
        'Twitter:OAuth.requestToken received an status differente than 200: \n' +
        'Status Code: ' + response.statusCode + '\n' +
        'Body: \n' + body
      ));
    }

    var qs = require('querystring');

    return callback(null, qs.parse(body));

  });
};

Public: get an access token

Parameters

• token - String with oauth_token
• verifier - String with oauth_verifier
• callback - Callback Function

Returns

A Callback with an Error object as first parameter if there was (otherwise just null) and an Object with the response with the model:

{
  oauth_token: String,
  oauth_token_secret: String,
  user_id: String,
  screen_name: String
}

Example

After running either oauth.authenticate or oauth.authorize and making the proper request to twitter’s servers you will end up with a token and a verifier. Suppose they are stored each in a variable of the same name, then:

oauth.accessToken(token, verifier, function (err, response) {
  if (err)
    throw (err);

  console.log(response);
});

With the data from that response you can initialize the API module and start GET‘ing and POST‘ing with user context as Twitter calls it.

Code

OAuth.prototype.accessToken = function(token, verifier, callback) {
  var self = this;
  var request = require('request');

  [token, verifier].forEach(function (item) {
    if (item == null) {
      return callback(new Error(
        'Twitter:OAuth.accessToken requires all the arguments to work.'
      ));
    }
  });
  
  var oauth = {
    consumer_key: self.opts.consumer_key,
    consumer_secret: self.opts.consumer_secret,
    token: token,
    verifier: verifier
  };

  request({
    method: 'POST',
    uri: self.uri.accessToken,
    oauth: oauth
  }, function(err, response, body) {
    if (err)
      return callback(err);

    var qs = require('querystring');

    return callback(null, qs.parse(body));
  });

};

Public: get authenticate URL

Parameters

• token - [Required] String with oauth_token from OAuth.requestToken.
• cb - Callback Function

Returns

A Callback with an Error object as the first parameter and a String with the URL to which redirect users as second parameter.

Example

oauth.authenticate(token, function (err, response) {
  if (err)
    throw err;

  console.log(response);
  /* https://api.twitter.com/oauth/authenticate?oauth_token= + token provided */
});

Code

OAuth.prototype.authenticate = function(token, cb) {
  helper.authyThing.call(this, 'authenticate', token, cb);
};

Public: get authorize URL

Parameters

• token - [Required] String with oauth_token from OAuth.requestToken.
• cb - Callback Function

Returns

A Callback with an Error object as the first parameter and a String with the URL to which redirect users as second parameter.

Example

oauth.authorize(token, function (err, response) {
  if (err)
    throw err;

  console.log(response);
  /* https://api.twitter.com/oauth/authorize?oauth_token= + token provided */
});

Code

OAuth.prototype.authorize = function(token, cb) {
  helper.authyThing.call(this, 'authorize', token, cb);
};

module.exports = OAuth;