ConsoleCommandDiscovery

Reads the metadata of every command declared in an assembly, without constructing any of them. Use it to build a help listing or a command reference. Reflection runs on every call, so a listing shown often should be built once and held rather than rebuilt each time.

GetAllCommands

Builds the metadata for each command class, reading the class attributes and the parameters of its ExecuteAsync method. A class that breaks the command rules throws InvalidOperationException naming it, the same failure RegisterConsoleCommands raises.

The overload taking no argument scans the calling assembly. Pass assemblies explicitly when the commands live in another project; an empty array yields nothing.

using AlmightyShogun.ConsoleCommands;

[Alias("?")]
[ConsoleCommand("help", "Lists the available commands.")]
public sealed class HelpCommand : ConsoleCommandBase
{
    private static readonly IReadOnlyList<ConsoleCommand> _commands =
        ConsoleCommandDiscovery.GetAllCommands();

    public Task ExecuteAsync()
    {
        foreach (ConsoleCommand command in _commands)
        {
            Console.WriteLine(command.Usage);

            if (command.Description is not null)
                Console.WriteLine($"    {command.Description}");
        }

        return Task.CompletedTask;
    }
}

WARNING

This does not apply SkipAutoRegistrationAttribute, which registration does. A command carrying that attribute appears in a listing built from here while being unreachable at the prompt.

Type signature

public static IReadOnlyList<ConsoleCommand> GetAllCommands();

public static IReadOnlyList<ConsoleCommand> GetAllCommands(
    Assembly[] assemblies
);