tianbar-1.2.0.0: scripts/dbus.js

/*
 * A plugin to receive DBus events.
 *
 * Requires 'jquery' to be available through RequireJS.
 */
define(['jquery', './tianbar'], function ($, tianbar) {
  "use strict";
  function copyProperties(properties, from, to) {
    $.each(properties, function(_, x) {
      if (x in from) {
        to[x] = from[x];
      }
    });
  }

  function stripVariants(obj) {
    if (obj.hasOwnProperty('__variant')) {
      return stripVariants(obj.__variant);
    }
    if (obj instanceof Array) {
      return obj.map(stripVariants);
    }
    if (obj instanceof Object) {
      const result = {};
      for (var key in obj) {
        if (obj.hasOwnProperty(key)) {
          result[key] = stripVariants(obj[key]);
        }
      }
      return result;
    }
    return obj;
  }

  function toObjectPath (str) {
    return {__object_path: str};
  }

  function fromObjectPath (op) {
    return op.__object_path;
  }

  function bus(busName) {
    return {
      /**
       * Listen for a particular DBus event.
       * @param match {Object} DBus match conditions ('path', 'iface',
       * 'member'), as well as 'direct' to only add the listener without
       * calling AddMatch (for direct connections)
       * @param handler {Function} The function to call upon receiving the event
       * @returns {Deferred} Promise to be fulfilled with a Tianbar event object
       */
      listen: function (match) {
        var data = {};
        copyProperties([
          'path',
          'iface',
          'member',
          'direct'
        ], match, data);
        return $.ajax('tianbar:///dbus/' + busName + '/listen', {
          data: data
        }).then(tianbar.createEvent).then(function (evt) {
          return evt.callback;
        });
      },

      /**
       * Stop listening for a DBus event.
       * @param evt {Event} A Tianbar event object returned by listen().
       */
      removeMatch: function (evt) {
        $.ajax('tianbar:///dbus/' + busName + '/stop', {
          data: {
            index: evt.index
          }
        });
      },

      /**
       * Call a DBus method.
       * @param params {Object} Method call details ('path', 'iface', 'member',
       * 'destination', 'body')
       * @return {Deferred} A promise to be fulfilled or rejected with the result
       */
      call: function (params) {
        var data = {};
        copyProperties(
          ['iface', 'member', 'destination'], params, data);
        if (params.path) {
          data.path = fromObjectPath(params.path);
        }
        data.body = JSON.stringify(params.body);
        // Prevent caching
        data.random = new Date().getTime();
        var deferred = $.Deferred();

        $.ajax('tianbar:///dbus/' + busName + '/call', {
          data: data
        }).done(function (result) {
          result = JSON.parse(result);
          if (result.Right) {
            result = stripVariants(result.Right.body)[0];
            deferred.resolve(result);
          } else {
            deferred.reject(result.Left);
          }
        });

        return deferred;
      },

      /**
       * Get an object property.
       * @param destination {String} Destination
       * @param path {String} Path
       * @param object {String} Object to get the property of
       * @param property {String} Property to get
       * @return {Deferred} A promise to be fulfilled or rejected with the
       * result
       */
      getProperty: function (destination, path, object, property) {
        return this.call({
          'destination': destination,
          'path': path,
          'iface': 'org.freedesktop.DBus.Properties',
          'member': 'Get',
          'body': [
            object,
            property
          ]
        });
      },

      /**
       * Get all object properties.
       * @param destination {String} Destination
       * @param path {String} Path
       * @param object {String} Object to get the property of
       * @return {Deferred} A promise to be fulfilled or rejected with the
       * result
       */
      getAllProperties: function (destination, path, object) {
        return this.call({
          'destination': destination,
          'path': path,
          'iface': 'org.freedesktop.DBus.Properties',
          'member': 'GetAll',
          'body': [
            object
          ]
        });
      }
    };
  }

  /**
   * Connect to an arbitrary bus.
   * @param address {String} Bus address
   * @return {Deferred} A promise to be fulfilled with the bus object
   */
  function connectBus(address) {
    // random name
    var name = new Date().getTime();

    return $.ajax('tianbar:///dbus/connect', {
      data: {
        name: name,
        address: address
      }
    }).then(function () {
      return bus(name);
    });
  }

  return {
    /**
     * Session bus.
     */
    session: bus('session'),
    /**
     * System bus.
     */
    system: bus('system'),
    /**
     * Connect an arbitrary bus.
     */
    connect: connectBus,
    /**
     * Convert a string to an object path.
     */
    toObjectPath: toObjectPath,
    /**
     * Convert an object path to string.
     */
    fromObjectPath: fromObjectPath
  };
});