Permissions

Permissions are the feature allowing you to determine if a player is able to perform an action or not.

Permission is an immutable class that can be added to any PermissionHandler.

A permission contains 2 things, a unique name (same as with Bukkit if you are familiar with it), and an optional NBTCompound which can be used to add additional data to the permission (no more "my.permission.X" where X represents a number).

Handling permission access

In order to add a permission to a PermissionHandler you should use PermissionHandler#addPermission(Permission).

To remove a permission, PermissionHandler#removePermission(Permission) and PermissionHandler#removePermission(String) are available.

Checking permissions

To verify if a PermissionHandler has a permission, you have the choice between simply checking if the handler has a permission with the same name, or verifying that the handler has both the permission name and the right data associated with it.

To check if the handler has a permission with a specific name, PermissionHandler#hasPermission(String) should be used. If you want to verify that the handler has the right NBT data PermissionHandler#hasPermission(String, PermissionVerifier) is the right choice.

A PermissionVerifier is a simple functional interface used to check if the given NBTCompound is valid.

Alternatively, PermissionHandler#hasPermission(Permission) can be used. It does require both the permission name and the data to be equal.

Adding permissions to players and checking them

In order to add a permission to a player, you will have to call the Player#addPermission(Permission) function, an example of proper usage would be

player.addPermission(new Permission("operator"));

If you want to check, if a player has a permission, you can use the Player#hasPermission(Permission) function, here is an example of checking for a permission inside of a command:

public class StopCommand extends Command {
    public StopCommand() {
        super("stop");
        setCondition((sender, commandString) -> sender.hasPermission(new Permission("operator"));
        setDefaultExecutor((sender, context) -> MinecraftServer.stopCleanly());
    }
}

Permission wildcard matching

Minestom supports wildcard matching for permissions. This means that if a player has a permission like admin.*, this will satisfy any checks for permissions that have the same format, with differing contents for the wildcard. e.g. admin.tp will return true.

Example:

player.addPermission(new Permission("command.*")); // Gives the player every permission with the 'command.' prefix

player.hasPermission(new Permission("command.gamemode")); // This returns true

// Same thing goes for
player.addPermission(new Permission("*")); // Gives the player every permission

player.hasPermission(new Permission("user.chat")); // returns true
player.hasPermission(new Permission("3i359cvjm.sdfk239c")); // returns true

Permission serialisation

Nothing is automatically saved persistently in Minestom, permissions are not an exception.

Permissions must be serialized and deserialized back manually if you want such a feature. You are lucky since the Permission class can easily be interpreted as 2 strings, one being the permission name, and the second representing the optional data using NBTCompound#toSNBT() (and deserialized with SNBTParser#parse()).