Discord.js get Roles of a user by id: cannot read properties

Question

I want to make a Discord.js bot that just checks if a member with the given ID has a role (by id). I know this is a duplicate, but .cache doesn't work for me, so I used the guild.members.fetch function:

const { Client, Intents, GuildMemberManager } = require('discord.js');
const { token, server_id } = require('./config.json');

// Create a new client instance
const client = new Client({ intents: [Intents.FLAGS.GUILDS] });

// When the client is ready, run this code (only once)
client.once('ready', () => {
    console.log('Ready!');
});

function validateUser(user_id) {
  const guild = server_id;
  guild.members.fetch(user_id)
  .then(console.log)
  .catch(console.error);
}

validateUser(491553591434412057)

// Login to Discord with your client's token
client.login(token);

However, I run into an error:

TypeError: Cannot read properties of undefined (reading ‘fetch‘).

Does anyone know a better way to get the roles without a written message etc. or how to fix this?

Answer 1

The problem is that your guild is not a guild but a string ( server_id ). You'll need to get the guild by this id:

const guild = client.guilds.cache.get(server_id);
if (!guild)
  return console.log(`Can't find the guild with ID ${server_id}`);

guild.members.fetch(user_id)
  .then(member => {
    // member.roles.cache is a collection of roles the member has
    console.log(member.roles.cache)

    if (member.roles.cache.has('ROLE ID'))
      console.log('member has the role')
  })
  .catch(console.error);