jscrambler-client.js

'use strict';
var _ = require('lodash');
var crypto = require('crypto');
var fs = require('fs');
var needle = require('needle');
var querystring = require('querystring');
var url = require('url');
/**
 * @class JScramblerClient
 * @param {Object} options
 * @param {String} options.accessKey
 * @param {String} options.secretKey
 * @param {String} [options.host=api.jscrambler.com]
 * @param {String} [options.port=443]
 * @param {String} [options.apiVersion=3]
 * @author José Magalhães (magalhas@gmail.com)
 * @license MIT <http://opensource.org/licenses/MIT>
 */
function JScramblerClient (options) {
  /**
   * @member
   */
  this.options = _.defaults(options || {}, {
    accessKey: null,
    secretKey: null,
    host: 'api.jscrambler.com',
    port: 443,
    apiVersion: 3
  });
  if (!this.options.accessKey || !this.options.secretKey)
    throw new Error('Missing access or secret keys');
}
/**
 * Builds the request URL. In case of being a POST it doesn't append data to
 the query string.
 * @private
 * @memberof JScramblerClient
 * @param {String} method
 * @param {String} path
 * @param {Object} params
 * @returns {String} The request path.
 */
function buildPath (method, path, params) {
  var query = '';
  if (method !== 'POST') {
    query = '?' + querystring.stringify(signedParams.apply(this, arguments));
  }
  return '/v' + this.options.apiVersion + path + query;
}
/**
 * It builds a query string sorted by key.
 * @private
 * @static
 * @param {Object} params
 * @memberof JScramblerClient
 * @returns {String} The query string.
 */
function buildSortedQuery (params) {
  // Sorted keys
  var keys = _.keys(params).sort();
  var query = '';
  for (var i = 0, l = keys.length; i < l; i++)
    query += encodeURIComponent(keys[i]) + '=' + encodeURIComponent(params[keys[i]]) + '&';
  // Strip the last separator and return
  return query.substring(0, query.length - 1);
}
/**
 * Generates the needed HMAC signature for the request.
 * @memberof JScramblerClient
 * @param {String} method
 * @param {String} path
 * @param {Object} params
 * @returns {String} The digested signature.
 */
function generateHmacSignature (method, path, params) {
  var paramsCopy = _.clone(params);
  for (var key in params) {
    if (key.indexOf('file_') !== -1) {
      paramsCopy[key] = crypto.createHash('md5').update(
        fs.readFileSync(params[key].file)).digest('hex');
    }
  }
  var signatureData = method.toUpperCase() + ';' + this.options.host.toLowerCase() +
    ';' + path + ';' + buildSortedQuery(paramsCopy);
  var hmac = crypto.createHmac('sha256', this.options.secretKey.toUpperCase());
  hmac.update(signatureData);
  return hmac.digest('base64');
}
/**
 * Iterate each passed file inside params.files and creates the corresponding
 params.file_{index}. It deletes params.files after iterating.
 * @private
 * @static
 * @memberof JScramblerClient
 * @param {String} method
 * @param {String} path
 * @param {Object} params
 */
function handleFileParams (params) {
  if (params.files) {
    for (var i = 0, l = params.files.length; i < l; i++) {
      params['file_' + i] = {
        file: params.files[i],
        content_type: 'application/octet-stream'
      };
    }
    delete params.files;
  }
}
/**
 * Signs all the parameters.
 ^ @private
 * @memberof JScramblerClient
 * @param {String} method
 * @param {String} path
 * @param {Object} params
 * @returns {Object} Params containing the access_key, timestamp and signature
 properties.
 */
function signedParams (method, path, params) {
  _.defaults(params, {
    access_key: this.options.accessKey,
    timestamp: new Date().toISOString()
  });
  if (method === 'POST' && params.files) handleFileParams(params);
  params.signature = generateHmacSignature.apply(this, arguments);
  return params;
}
/**
 * Delete request.
 * @param {String} path
 * @param {Object} params
 * @param {Callback} callback
 */
JScramblerClient.prototype.delete = function (path, params, callback) {
  this.request('DELETE', path, params, callback);
};
/**
 * Get request.
 * @param {String} path
 * @param {Object} params
 * @param {Callback} callback
 */
JScramblerClient.prototype.get = function (path, params, callback) {
  this.request('GET', path, params, callback);
};
/**
 * HTTP request.
 * @param {String} method
 * @param {String} path
 * @param {Object} params
 * @param {Callback} callback
 */
JScramblerClient.prototype.request = function (method, path, params, callback) {
  var signedData;
  var options = {};
  if (!params) params = {};
  // If post sign data and set the request as multipart
  if (method === 'POST') {
    signedData = signedParams.apply(this, arguments);
    options.multipart = true;
  }
  // Format URL
  var protocol = this.options.port === 443 ? 'https' : 'http';
  var formatedUrl = url.format({
    hostname: this.options.host,
    port: this.options.port,
    protocol: protocol
  }) + buildPath.call(this, method, path, params);
  needle.request(method, formatedUrl, signedData || params, options, callback);
};
/**
 * Post request.
 * @param {String} path
 * @param {Object} params
 * @param {Callback} callback
 */
JScramblerClient.prototype.post = function (path, params, callback) {
  this.request('POST', path, params, callback);
};

exports = module.exports = JScramblerClient;