code: function (db, id, wantedPropsFromMetadata, cb) {
  			if(Object.prototype.toString.call(wantedPropsFromMetadata) == '[object Function]'){
  				cb = wantedPropsFromMetadata;
  				wantedPropsFromMetadata = [];
  			}
  			var url = host + 'databases/' + db + '/docs/' + id;
  			request(url, function (error, response, body) {
  				if(error || response.statusCode != 200)
  					return cb(error || new Error(response.statusCode));
  				var doc = JSON.parse(body);
  				var meta = _.reduce(response.headers
  					, function (memo, val, key) {
  						if (key.indexOf('raven') === 0 || wantedPropsFromMetadata.indexOf(key) != -1)
  							memo[key] = val;
  						return memo;
  					}, {});
  				meta['@id'] = response.headers['__document_id'];
  				meta.etag = response.headers['etag'];
  				meta.dateCreated = response.headers['DateCreated'] || response.headers['datecreated'];
  				doc['@metadata'] = meta;
  				cb(null, doc);
  			});
  		}
docs: Loads document with given id.
  @param {string} db
  @param {string} id
  @param {string} wantedPropsFromMetadata(OPTIONAL)
  @param {Function} cb