Message Commands

Message commands, which are generally considered 'Legacy', are a way to run commands on Discord bots using regular messages. Before the introduction of Slash/Chat Input Commands, this was the primary way commands were handled. They were usually triggered by using a prefix set by the developer of the bot (for example: !ping).

warning

While CommandKit allows developers to create and handle message commands, it's important to note that Discord generally discourages message commands in favor of the more modern Chat Input Commands.

Basic setup

Message commands, like all the other command types, live in your src/app/commands directory. To let CommandKit know that this is a message command, just export the message function from your command file.

src/app/commands/ping.ts

import type { CommandData, MessageCommand } from 'commandkit';

export const command: CommandData = {
  name: 'ping',
};

export const message: MessageCommand = async (ctx) => {
  await ctx.message.reply('Pong!');
};

Message command options (arguments)

Since a message command - on a technical level - is just a string, the idea of message command options will be different compared to chat input command options. Instead of getting parsed data, you'll essentially be dealing with string 'arguments'.

src/app/commands/ping.ts

import type { CommandData, MessageCommand } from 'commandkit';

export const command: CommandData = {
  name: 'ping',
};

export const message: MessageCommand = async (ctx) => {
  const args = ctx.message.args(); // string[]
};

With the above command as an example, if a user on Discord runs !ping john jack jane, the value of args will equal ['john', 'jack', 'jane'].

Custom prefixes

The simplest way to set a custom prefix is using the setPrefixResolver method on the commandkit instance:

src/app.ts

import { commandkit } from 'commandkit';

commandkit.setPrefixResolver(async (message) => {
  return '?';
});

This sets a global prefix of ? for all message commands. Your bot will now respond to commands like ?help or ?ping.

tip

You can return an array of strings to support multiple prefixes simultaneously:

return ['?', '!', '>'];

Guild-specific prefixes

For a more dynamic approach, you might want different prefixes for different guilds. Here's how to implement that:

src/app.ts

import { commandkit } from 'commandkit';
import { database } from '../database'; // This is a mock database

commandkit.setPrefixResolver(async (message) => {
  if (!message.guildId) {
    return '!'; // Fallback to '!' if command is used in a DM
  }

  const guildSettings = await database.findUnique({
    where: {
      guildId: message.guildId,
    },
    select: {
      prefix: true,
    },
  });

  return guildSettings?.prefix ?? '!'; // Fallback to '!' if no prefix is found
});

warning

The setPrefixResolver method runs on every message, so it's important to make sure that it's as lightweight as possible. To help with performance, you may want to implement caching, which CommandKit also supports with the @commandkit/cache official plugin.