code: function identify(path, callback) {
        return self.identifyLocalImage(path, function(err, info) {
          if (err) {
            return callback(err);
          }
          context.info = info;
          context.extension = info.extension;
          return callback(null);
        });
      }
docs: Identify the file type, size, etc. Stuff them into context.info and context.extension