extensions/renderer/resources/permissions_custom_bindings.js

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 // Custom binding for the Permissions API.
   6
   7 var binding = require('binding').Binding.create('permissions');
   8
   9 var Event = require('event_bindings').Event;
  10
  11 // These custom binding are only necessary because it is not currently
  12 // possible to have a union of types as the type of the items in an array.
  13 // Once that is fixed, this entire file should go away.
  14 // See,
  15 // https://code.google.com/p/chromium/issues/detail?id=162044
  16 // https://code.google.com/p/chromium/issues/detail?id=162042
  17 // TODO(bryeung): delete this file.
  18 binding.registerCustomHook(function(api) {
  19   var apiFunctions = api.apiFunctions;
  20   var permissions = api.compiledApi;
  21
  22   function maybeConvertToObject(str) {
  23     var parts = $String.split(str, '|');
  24     if (parts.length != 2)
  25       return str;
  26
  27     var ret = {};
  28     ret[parts[0]] = JSON.parse(parts[1]);
  29     return ret;
  30   }
  31
  32   function convertObjectPermissionsToStrings() {
  33     if (arguments.length < 1)
  34       return arguments;
  35
  36     var args = arguments[0].permissions;
  37     if (!args)
  38       return arguments;
  39
  40     for (var i = 0; i < args.length; i += 1) {
  41       if (typeof(args[i]) == 'object') {
  42         var a = args[i];
  43         var keys = $Object.keys(a);
  44         if (keys.length != 1) {
  45           throw new Error("Too many keys in object-style permission.");
  46         }
  47         arguments[0].permissions[i] = keys[0] + '|' +
  48             JSON.stringify(a[keys[0]]);
  49       }
  50     }
  51
  52     return arguments;
  53   }
  54
  55   // Convert complex permissions to strings so they validate against the schema
  56   apiFunctions.setUpdateArgumentsPreValidate(
  57       'contains', convertObjectPermissionsToStrings);
  58   apiFunctions.setUpdateArgumentsPreValidate(
  59       'remove', convertObjectPermissionsToStrings);
  60   apiFunctions.setUpdateArgumentsPreValidate(
  61       'request', convertObjectPermissionsToStrings);
  62
  63   // Convert complex permissions back to objects
  64   apiFunctions.setCustomCallback('getAll',
  65       function(name, request, response) {
  66         for (var i = 0; i < response.permissions.length; i += 1) {
  67           response.permissions[i] =
  68               maybeConvertToObject(response.permissions[i]);
  69         }
  70
  71         // Since the schema says Permissions.permissions contains strings and
  72         // not objects, validation will fail after the for-loop above.  This
  73         // skips validation and calls the callback directly, then clears it so
  74         // that handleResponse doesn't call it again.
  75         try {
  76           if (request.callback)
  77             $Function.apply(request.callback, request, [response]);
  78         } finally {
  79           delete request.callback;
  80         }
  81       });
  82
  83   // Also convert complex permissions back to objects for events.  The
  84   // dispatchToListener call happens after argument validation, which works
  85   // around the problem that Permissions.permissions is supposed to be a list
  86   // of strings.
  87   permissions.onAdded.dispatchToListener = function(callback, args) {
  88     for (var i = 0; i < args[0].permissions.length; i += 1) {
  89       args[0].permissions[i] = maybeConvertToObject(args[0].permissions[i]);
  90     }
  91     $Function.call(Event.prototype.dispatchToListener, this, callback, args);
  92   };
  93   permissions.onRemoved.dispatchToListener =
  94       permissions.onAdded.dispatchToListener;
  95 });
  96
  97 exports.binding = binding.generate();