deploy-commands.js

const { SlashCommandBuilder } = require('@discordjs/builders');
const fs = require('fs');
const { REST } = require('@discordjs/rest');
const { Routes } = require('discord-api-types/v9');
require('dotenv').config({ path: '.env.develop'});
const clientId = process.env.CLIENT_ID;
const guildId = process.env.GUILD_ID;
const token = process.env.TOKEN;

const commands = [];
const commandFiles = fs.readdirSync('./commands').filter(file => file.endsWith('.js'));

for (const file of commandFiles){
  const command = require(`./commands/${file}`);
  commands.push(command.data.toJSON());
}

const rest = new REST({version: '9'}).setToken(token);

rest.put(Routes.applicationGuildCommands(clientId, guildId), { body: commands })
  .then(() => console.log("Succeessfully registered application commands."))
  .catch(console.error);