| 1 | var events = require('events'), |
| 2 | util = require('util'), |
| 3 | _ = require('lodash'), |
| 4 | EventPublisher = require('./plugininterface.js'); |
| 5 | |
| 6 | |
| 7 | /** |
| 8 | * Publisher |
| 9 | * The main point in which events are fired and bound to |
| 10 | */ |
| 11 | |
| 12 | // Where events are bound to |
| 13 | var active_publisher; |
| 14 | |
| 15 | |
| 16 | // Create a publisher to allow event subscribing |
| 17 | function Publisher (obj) { |
| 18 | var EventPublisher = require('./plugininterface.js'); |
| 19 | return new EventPublisher(); |
| 20 | } |
| 21 | |
| 22 | |
| 23 | // Register an already created Publisher() as the active instance |
| 24 | function registerPublisher (obj) { |
| 25 | active_publisher = obj; |
| 26 | } |
| 27 | |
| 28 | |
| 29 | |
| 30 | |
| 31 | |
| 32 | |
| 33 | /** |
| 34 | * Keeping track of modules |
| 35 | */ |
| 36 | |
| 37 | // Hold the loaded modules |
| 38 | var registered_modules = []; |
| 39 | |
| 40 | function loadModule (module_file) { |
| 41 | var module, |
| 42 | full_module_filename = global.config.module_dir + module_file; |
| 43 | |
| 44 | // Get an instance of the module and remove it from the cache |
| 45 | try { |
| 46 | module = require(full_module_filename); |
| 47 | delete require.cache[require.resolve(full_module_filename)]; |
| 48 | } catch (err) { |
| 49 | // Module was not found |
| 50 | return false; |
| 51 | } |
| 52 | |
| 53 | return module; |
| 54 | } |
| 55 | |
| 56 | |
| 57 | // Find a registered collection, .dispose() of it and remove it |
| 58 | function unloadModule (module) { |
| 59 | var found_module = false; |
| 60 | |
| 61 | registered_modules = _.reject(registered_modules, function (registered_module) { |
| 62 | if (module.toLowerCase() === registered_module.module_name.toLowerCase()) { |
| 63 | found_module = true; |
| 64 | |
| 65 | registered_module.dispose(); |
| 66 | return true; |
| 67 | } |
| 68 | }); |
| 69 | |
| 70 | return found_module; |
| 71 | } |
| 72 | |
| 73 | |
| 74 | |
| 75 | |
| 76 | |
| 77 | |
| 78 | /** |
| 79 | * Module object |
| 80 | * To be created by modules to bind to server events |
| 81 | */ |
| 82 | function Module (module_name) { |
| 83 | registered_modules.push(this); |
| 84 | this.module_name = module_name; |
| 85 | |
| 86 | // Holder for all the bound events by this module |
| 87 | this._events = {}; |
| 88 | } |
| 89 | |
| 90 | |
| 91 | |
| 92 | // Keep track of this modules events and bind |
| 93 | Module.prototype.on = function (event_name, fn) { |
| 94 | var internal_events = ['dispose']; |
| 95 | |
| 96 | this._events[event_name] = this._events[event_name] || []; |
| 97 | this._events[event_name].push(fn); |
| 98 | |
| 99 | // If this is an internal event, do not propogate the event |
| 100 | if (internal_events.indexOf(event_name) === -1) { |
| 101 | active_publisher.on(event_name, fn); |
| 102 | } |
| 103 | }; |
| 104 | |
| 105 | |
| 106 | // Keep track of this modules events and bind once |
| 107 | Module.prototype.once = function (event_name, fn) { |
| 108 | this._events[event_name] = this._events[event_name] || []; |
| 109 | this._events[event_name].push(fn); |
| 110 | |
| 111 | active_publisher.once(event_name, fn); |
| 112 | }; |
| 113 | |
| 114 | |
| 115 | // Remove any events by this module only |
| 116 | Module.prototype.off = function (event_name, fn) { |
| 117 | var idx; |
| 118 | |
| 119 | if (typeof event_name === 'undefined') { |
| 120 | // Remove all events |
| 121 | this._events = []; |
| 122 | |
| 123 | } else if (typeof fn === 'undefined') { |
| 124 | // Remove all of 1 event type |
| 125 | delete this._events[event_name]; |
| 126 | |
| 127 | } else { |
| 128 | // Remove a single event + callback |
| 129 | for (idx in (this._events[event_name] || [])) { |
| 130 | if (this._events[event_name][idx] === fn) { |
| 131 | delete this._events[event_name][idx]; |
| 132 | } |
| 133 | } |
| 134 | } |
| 135 | |
| 136 | active_publisher.off(event_name, fn); |
| 137 | }; |
| 138 | |
| 139 | |
| 140 | |
| 141 | // Clean up anything used by this module |
| 142 | Module.prototype.dispose = function () { |
| 143 | // Call any dispose callbacks |
| 144 | (this._events['dispose'] || []).forEach(function (callback) { |
| 145 | callback(); |
| 146 | }); |
| 147 | |
| 148 | // Remove all bound event listeners |
| 149 | this.off(); |
| 150 | }; |
| 151 | |
| 152 | |
| 153 | |
| 154 | |
| 155 | |
| 156 | |
| 157 | module.exports = { |
| 158 | // Objects |
| 159 | Module: Module, |
| 160 | Publisher: Publisher, |
| 161 | |
| 162 | // Methods |
| 163 | registerPublisher: registerPublisher, |
| 164 | load: loadModule, |
| 165 | unload: unloadModule, |
| 166 | getRegisteredModules: function () { return registered_modules; } |
| 167 | }; |