500px api connection

gistfile1.js

/**
 * Function generates parts of URI paramaters.
 * @param param_name as String.
 * @param root as String representing the root paramater in an array.
 */
encodeParamName = function(param_name, root) {
  if (root) return encodeURIComponent(root + '[' + param_name + ']');
  else return encodeURIComponent(param_name);
};

/**
 * Function takes object and returns it's parts as a string of paramaters
 * for use in a URI.
 * @param object as Object.
 * @param use as String (used for recursion).
 * @return String as paramaters for URI.
 */
objectToParams = function(object, root) {
  var string_parts = [];

  // Loop through object, extract all properties and append them
  // to the string_parts array.
  for (var property in object) {
    if (object.hasOwnProperty(property)) {
      var value = object[property];
      if (value instanceof Array) {
        // Property is an array.
        for (var i = 0; i < value.length; i++) {
          var encoded_value = encodeURIComponent(value[i]),
            param_name = this.encodeParamName(property, root);
          string_parts.push(param_name + '%5B%5D=' + encoded_value);
        }
      } else if (typeof value == 'object') {
        // Property is an object.
        var param_name = this.encodeParamName(property, root);
        string_parts.push(objectToParams(value, param_name));
      } else {
        // Property is a string.
        var param_name = this.encodeParamName(property, root),
            URIComponent = encodeURIComponent(value);
        string_parts.push(param_name + '=' + URIComponent);
      }
    }
  }
  // Join our parts and return the string.
  return string_parts.join('&');
};
var params = {
  feature: 'popular',
  image_size: 4,
  consumer_key: 'EX4MPL3C0NSUM3RK3Y',
  callback: 'callback',
};
var url = 'https://api.500px.com/v1/' + 'photos.jsonp' + '?' + objectToParams(params);

  // Construct JSONP request
  tag = document.createElement('script');
  tag.src = url;
  document.body.appendChild(tag);