Commands Handler

The commands handler is a class that intercepts all commands registered by an addon. That allows the library to parse arguments and trigger the registered callbacks.

As mentioned in the overview, one of the motivations behind the commands structure is to allow commands to behave as objects, and that's possible leaving all the command conditionals, parsing, etc, to the handler, requiring commands to just expose a callback expecting the desired arguments.

• See how to register commands here

How it works

1. When an addon initializes its library instance, it can pass a property in the constructor representing the addon main command. That will make the library register the command during its initialization.
2. The library registers the command associating its own callback at this point.
3. After that, each add(command) call will map its operation and the command itself.
4. When the command is executed in game, the library will have its callback triggered along with the argument, which is broken by spaces.
   • When a command is executed in the game, everything after the command itself becomes the argument. Example: /myCommand arg1 arg2 arg3 will trigger the callback with arg1 arg2 arg3.
   • The Stormwind Library commands handler was designed to forward the arguments like an operating system console where arguments are separated by blank spaces. Arguments that must contain spaces can be wrapped by " or '. Example: /myCommand arg1 "arg2 arg3" will result in two arguments {'arg1', 'arg2 arg3'}.
5. This list of arguments are divided, and the first argument is considered the command operation, so it will determine the proper callback to trigger in the addon. This callback is the one exposed by the command object.
6. The other arguments (if any) are then validated by the command instance validator (if provided) and when valid, passed to the operation callback.

The help operation

By default, the commands handler offers a help operation that behaves as a normal command. It basically prints all the available operations (except for the help itself) along with their descriptions.

Addons that must need to override the help operation, simply create a command and add it normally, so the default one will be replaced.

The commands handler was updated in version 1.5.0 to also consider the help operation as the default one when no operation is passed. With that change, raw commands like /myCommand will work the same as /myCommand help.