Nuxt/examples/auth-routes/nuxt.config.js

const bodyParser = require('body-parser')
const session = require('express-session')

module.exports = {
  head: {
    title: 'Auth Routes',
    meta: [
      { charset: 'utf-8' },
      { name: 'viewport', content: 'width=device-width, initial-scale=1' },
      { hid: 'description', content: 'Auth Routes example' }
    ]
  },
  /*
  ** Add server middleware
  ** Nuxt.js uses `connect` module as server
  ** So most of express middleware works with nuxt.js server middleware
  */
  serverMiddleware: [
    // body-parser middleware
    bodyParser.json(),
    // session middleware
    session({
      secret: 'super-secret-key',
      resave: false,
      saveUninitialized: false,
      cookie: { maxAge: 60000 }
    }),
    // Api middleware
    // We add /api/login & /api/logout routes
    '~/api'
  ]
}