scriptcraft/docs/release-notes.md

2014 03 15

Version 2.0.6

Simplified Event handling code.

The callback function for event handling now only takes 1 single parameter, the event which triggered the callback. The listener object is bound to the callback function so within the callback function this refers to the listener object. Unregistering listeners has also been greatly simplified. You can have an event handler which fires only once by unregistering itself within the callback like this...

events.on('player.PlayerJoinEvent', function( event ) { 

   // do something
   event.player.sendMessage( "You're the first player to join" );

   // unregister so this function is called only once ever.
   this.unregister();

});

The events.on() function also returns the same listener object as this refered to inside the callback. The listener object has a single method unregister() which can be called to stop listening for the event.

2014 03 12

Added Drone.MAX_VOLUME and Drone.MAX_SIDE properties to specify limits on size of Drone ops. This is to stop individual players from hogging the CPU in a classrom environment.

2014 03 08

Fixed issues #115 #122 #123

Improved background processing of Drone build commands.

2014 02 19

Version 2.0.5

Asynchronous building. Drone now builds asynchronously. Fixed Issue #119 (exceptions on reload/stop)

2014 02 11

Version 2.0.4

Various bug fixes, enhanced classroom module and improved error logging on startup.

2014 01 17

Added support for communication with Arduino and other devices which use the MQTT protocol via a new sc-mqtt module. This module requires a separate sc-mqtt.jar file downloadable from http://scriptcraftjs.org/download/extras/mqtt which must be included in the CraftBukkit classpath. If using MQTT in ScriptCraft, then Craftbukkit should be launched like this...

java -classpath craftbukkit.jar;sc-mqtt.jar org.bukkit.craftbukkit.Main

You can use the new sc-mqtt module like this to send and receive messages between minecraft and an Arduino. For example to send a message to the MQTT broker whenever a player breaks a block...

var mqtt = require('sc-mqtt');
var client = mqtt.client('tcp://localhost:1883','scripcraft');
client.connect();

events.on('block.BlockBreakEvent', function(listener, event){
    client.publish('minecraft','block-broken');
});

To have minecraft react to inputs from an MQTT broker...

var mqtt = require('sc-mqtt');
var client = mqtt.client('tcp://localhost:1883','scripcraft');
client.connect();
client.onMessageArrived(function(topic, message){
    var payload = message.payload;
    if (topic == 'arduino'){
       // do something with payload.
    }
});    

2014 01 14

Added config.yml file for configuration options. This file allows scriptcraft admins to turn on or off re-unzipping of the modules, plugins and lib folders when deploying a new version of scriptcraft. It's strongly recommended that the lib directory always be set to true to get the latest core scriptcraft code . The modules and plugins directories are optional and not part of scriptcraft core. The config.yml file looks like this...

extract-js:
  plugins: true
  modules: true
  lib: true

2014 01 13

Bug Fix: Make ScriptCraft work with Nashorn javascript engine bundled with Java 8 https://github.com/walterhiggins/ScriptCraft/issues/112

2014 01 12

Important

The ScriptCraft.jar file has been renamed scriptcraft.jar (see bug fix details below). This means that you will have to remove the existing plugins/ScriptCraft.jar file if present.

Bug Fix: On Mac OS, the plugins/scriptcraft directory is copied to plugins/ScriptCraftPlugin the 2nd time ScriptCraftPlugin is loaded. This has been fixed by changing the plugin name from ScriptCraftPlugin to scriptcraft. The jar file has also been rename from ScriptCraft.jar to scriptcraft.jar.

New command: jsp spawn lets in-game operators spawn any type of entity. For example /jsp spawn cow will spawn a cow at the in-game operator's current location.

New minigame: Cow Clicker. A simple demonstration of using Bukkit's Scoreboard API. Players click cows to score points. Scores are displayed in a side bar on screen. Players join or leave the game by typing /jsp cowclicker at the in-game prompt.

2014 01 05

Bug Fix: On Mac OS, alias plugin caused Exceptions due to missing .trim() function on String.

Changed target for compilation to 1.6 so that ScriptCraft will work with both java 1.6 and 1.7.

Added documentation for the Signs module.

2014 01 02

Added a warning in console at start-up if legacy directories are detected. Added 'use strict' to core modules. Bug Fix; Signs were not being saved. (introduced with recent change to JSONifying Location)

2014 01 01

'Buddha' Release - towards a total annihilation of the 'self' variable. The 'self' variable should only be used at the in-game or server console command prompts and should not be used in modules or in multi-threaded code.

Moved scriptcraft directory from {craftbukkit-root}/scriptcraft to {craftbukkit-root}/plugins/scriptcraft because this seems to be where other plugins create plugin-specific directories on the filesystem.

Documentation updates. Added new sections to the Young Persons Guide to Modding Minecraft.

2013 12 30

Removing coffeescript support because coffeescript.js will not compile/evaluate (generated bytecode exceeds 64K limit).

Updated plugin to remove self variable once the js command evaluation has completed (limits the scope of the self variable to just command-prompt evaluation).

2013 12 29

Bug Fix: Can't get Scriptcraft core libraries working.

Bug Fix; Server console errors when empty commands submitted.

Added more example modules.

2013 12 28

Documented the 'homes' module other tweaks to documentation.

2013 12 27

Updated 'jsp alias' command.

The 'jsp alias' command now lets players define their own shortcuts which don't require the 'jsp ' prefix.

Example

At the in-game prompt use the following command to create a new alias cw (short for change Clock & Weather) which will change the time and weather using a single statement.

/jsp alias set cw = time set {1} ; weather {2}

This creates a new cw alias which takes 2 parameters, time and weather and passes them to the 'time set' and 'weather' commands. You use the alias like this...

/cw 4000 sun

... which in turn gets converted into these 2 commands...

/time set 4000
/weather sun

Aliases can be set on a per-player basis or can be set globally (for all players). Aliases are automatically saved and restore on server shutdown/startup.

Added console global variable.

ScriptCraft now has a console global variable which can be used for logging (to the server console). The console variable uses the ScriptCraft plugin Logger object. You use the console object in your javascript modules like this...

console.info('Hello %s, %s', 'World', 'Universe');

... or simply...

console.warn('Hello World');

2013 12 26

Made the events variable global because it is use by modules and plugins. This means there is no longer any need to explicitly require('events') since events is now a free variable in the global namespace.

2013 12 25

Added the 'commando' module.

2013 12 24

'Modules' release

Modules in ScriptCraft

ScriptCraft now has a simple module loading system. ScriptCraft now uses the CommonJS module contract - that is - the same module system used by Node.js. All of the javascript code which comes bundled with ScriptCraft has been modified so that it conforms to the CommonJS module system.

What this means for plugins you've developed using ScriptCraft

If you have written plugins using a previous version of ScriptCraft then you have 2 options...

1. Continue using the previous version of ScriptCraft.
2. Update your plugins to work with the ScriptCraft 'Modules' release.

... Option 2 should be relatively straightforward if you follow these steps...

1. Copy your own custom plugins from the js-plugins directory to the new scriptcraft/plugins directory.
2. In your javascript code any functions, objects or variables which you want to expose for use by others should be exposed using the special exports variable. All other code within your .js files will now be private by default. See below for details on how CommonJS/Node.js modules work.

If you have any questions or concerns or need help converting your existing javascript plugin, contact please post questions on the ScriptCraft forum or open an issue on the Github project

In ScriptCraft, files and modules are in one-to-one correspondence. As an example, foo.js loads the module circle.js in the same directory. ScriptCraft now uses the same module system as Node.js - see Node.js Modules for more details.

The contents of foo.js:

var circle = require('./circle.js');
echo( 'The area of a circle of radius 4 is '
           + circle.area(4));

The contents of circle.js:

var PI = Math.PI;

exports.area = function (r) {
  return PI * r * r;
};

exports.circumference = function (r) {
  return 2 * PI * r;
};

The module circle.js has exported the functions area() and circumference(). To add functions and objects to the root of your module, you can add them to the special exports object.

Variables local to the module will be private, as though the module was wrapped in a function. In this example the variable PI is private to circle.js.

If you want the root of your module's export to be a function (such as a constructor) or if you want to export a complete object in one assignment instead of building it one property at a time, assign it to module.exports instead of exports.

Module Loading

When the ScriptCraft Java plugin is first installed, a new subdirectory is created in the craftbukkit directory. If your craftbukkit directory is called 'craftbukkit' then the new subdirectories will be ...

• craftbukkit/scriptcraft/
• craftbukkit/scriptcraft/plugins
• craftbukkit/scriptcraft/modules
• craftbukkit/scriptcraft/lib

... The plugins, modules and lib directories each serve a different purpose.

The plugins directory

At server startup the ScriptCraft Java plugin is loaded and begins automatically loading and executing all of the modules (javascript files with the extension .js) it finds in the scriptcraft/plugins directory. All modules in the plugins directory are automatically loaded into the global namespace. What this means is that anything a module in the plugins directory exports becomes a global variable. For example, if you have a module greeting.js in the plugins directory....

exports.greet = function() {
    echo('Hello ' + self.name);
};

... then greet becomes a global function and can be used at the in-game (or server) command prompt like so...

/js greet()

... This differs from how modules (in NodeJS and commonJS environments) normally work. If you want your module to be exported globally, put it in the plugins directory. If you don't want your module to be exported globally but only want it to be used by other modules, then put it in the modules directory instead. If you've used previous versions of ScriptCraft and have put your custom javascript modules in the js-plugins directory, then put them in the scriptcraft/plugins directory. To summarise, modules in this directory are ...

• Automatically loaded and run at server startup.
• Anything exported by modules becomes a global variable.

The modules directory

The module directory is where you should place your modules if you don't want to export globally. In javascript, it's considered best practice not to have too many global variables, so if you want to develop modules for others to use, or want to develop more complex mods then your modules should be placed in the modules directory. Modules in the modules directory are not automatically loaded at startup, instead, they are loaded and used by other modules/plugins using the standard require() function. This is the key difference between modules in the plugins directory and modules in the modules directory. Modules in the plugins directory are automatically loaded and exported in to the global namespace at server startup, modules in the modules directory are not.

The lib directory

Modules in the lib directory are for use by ScriptCraft and some core functions for use by module and plugin developers are also provided. The lib directory is for internal use by ScriptCraft. Modules in this directory are not automatically loaded nor are they globally exported.