cosette/plugins/socket.client.js

// Nuxt 3: plugins/socket.client.js
import io from 'socket.io-client'

export default defineNuxtPlugin(() => {
    const socket = io('http://localhost:3000')

    socket.on("message", (arg) => {
      console.log(arg); // "world"
    });

    return {
        provide: {
            socket: socket
        }
    }
})

export const socket = io('http://localhost:3000')