openclient/client/utils.js

An opinionated client for RESTful APIs (particularly OpenStack's).

module.exports = {
  urljoin: function () {
    // Constructs URLs with proper slashes regardless of leading/trailing
    // slashes on the arguments passed in.
    var url = "";

    for (var i = 0, j = arguments.length; i < j; i++) {
      var arg = arguments[i];

      if (typeof(arg) === "undefined") {
        continue;
      }

      arg = arg.toString();

      // Strip any preceding slashes since we append slashes to everything.
      if (arg.substr(0, 1) === "/") {
        arg = arg.substr(1);
      }
      // Add a trailing slash unless this is the end of URL.
      if (arg.substr(-1) !== "/" && i !== arguments.length - 1) {
        arg += "/";
      }
      // Join the current piece to our URL string.
      url += arg;
    }
    return url;
  },

  interpolate: function (string, mapping) {
    return string.replace(/\{([^{}]*)\}/g, function (pattern, lookup) {
      var replacement = mapping[lookup];
      return (typeof replacement === 'string' || typeof replacement === 'number') ? replacement : pattern;
    });
  },

  is_ans1_token: function (token) {
    // Credit goes to Adam Young for figuring this out. See Keystone's
    // source code for the logic/math that proves it.
    return token.indexOf("MII") === 0 ? true : false;
  },

  /**
   * For each `key`, `val` in each of `obj...`, set `target[key]` = `val` if `target[key]` is undefined
   */
  defaults: function(target /*, obj...*/) {
    var args = Array.prototype.slice.call(arguments, 0),
        current, key, val;

    args.shift();
    current = args.shift();
    while(current) {
      for (key in current) {
        if (typeof target[key] === "undefined") {
          target[key] = current[key];
        }
      }
      current = args.shift();
    }
    return target;
  }

};