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index.js

const express = require('express')
const consola = require('consola')
const apiConfig = require('./config')
const mongoose = require('mongoose')
const bodyParser = require('body-parser')
const passport = require('passport')
const LocalStrategy = require('passport-local').Strategy
const { Nuxt, Builder } = require('nuxt')

// Controller
const apiRouter = require('./routes')

const app = express()
const host = process.env.HOST || '127.0.0.1'
const port = process.env.PORT || 3000

mongoose.connect(
  apiConfig.mongoUrl,
  { useNewUrlParser: true }
)
let db = mongoose.connection
db.on('error', console.error.bind(console, 'connection error:'))
db.once('open', function() {
  app.set('port', port)

  // Import and Set Nuxt.js options
  let config = require('../nuxt.config.js')
  config.dev = !(process.env.NODE_ENV === 'production')

  async function start() {
    // Init Body Parser
    app.use(
      bodyParser.json({
        limit: apiConfig.bodyLimit
      })
    )

    // Init password crypting
    app.use(passport.initialize())
    let User = require('./model/user')
    passport.use(
      new LocalStrategy(
        {
          usernameField: 'username',
          passwordField: 'password'
        },
        User.authenticate()
      )
    )
    passport.serializeUser(User.serializeUser())
    passport.deserializeUser(User.deserializeUser())

    // Controller routing
    app.use('/api', apiRouter)

    // Init Nuxt.js
    const nuxt = new Nuxt(config)

    // Build only in dev mode
    if (config.dev) {
      const builder = new Builder(nuxt)
      await builder.build()
    }

    // Give nuxt middleware to express
    app.use(nuxt.render)

    // Listen the server
    app.listen(port, host)
    consola.ready({
      message: `Server listening on http://${host}:${port}`,
      badge: true
    })
  }
  start()
})

nuxt.config.js

const pkg = require('./package')

module.exports = {
  mode: 'universal',

  /*
  ** Headers of the page
  */
  head: {
    title: pkg.name,
    meta: [
      { charset: 'utf-8' },
      { name: 'viewport', content: 'width=device-width, initial-scale=1' },
      { hid: 'description', name: 'description', content: pkg.description }
    ],
    link: [
      {
        rel: 'icon',
        type: 'image/x-icon',
        href: '/favicon.ico'
      },
      {
        rel: 'stylesheet',
        href:
          'https://fonts.googleapis.com/css?family=Roboto:100,300,400,500,700,900|Material+Icons'
      }
    ]
  },

  /*
  ** Customize the progress-bar color
  */
  loading: { color: '#3B8070' },

  /*
  ** Global CSS
  */
  css: [{ src: '~/assets/style/app.styl', lang: 'styl'}],

  /*
  ** Plugins to load before mounting the App
  */
  plugins: ['~/plugins/vuetify.js'],

  /*
  ** Nuxt.js modules
  */
  modules: [
    // Doc: https://github.com/nuxt-community/axios-module#usage
    '@nuxtjs/axios'
  ],
  /*
  ** Axios module configuration
  */
  axios: {
    // See https://github.com/nuxt-community/axios-module#options
  },

  /*
  ** Build configuration
  */
  build: {
    extractCSS: true,
    /*
    ** You can extend webpack config here
    */
    extend(config, ctx) {
      // Run ESLint on save
      if (ctx.isDev && process.client) {
        config.module.rules.push({
          enforce: 'pre',
          test: /\.(js|vue)$/,
          loader: 'eslint-loader',
          exclude: /(node_modules)/
        })
      }
    }
  }
}

package.json

{
  "name": "lcoletta_blog",
  "version": "1.0.0",
  "description": "Blog de Léo Coletta",
  "author": "Léo Coletta",
  "private": true,
  "scripts": {
    "dev": "cross-env NODE_ENV=development nodemon server/index.js --watch server",
    "build": "nuxt build",
    "start": "cross-env NODE_ENV=production node server/index.js",
    "generate": "nuxt generate",
    "lint": "eslint --ext .js,.vue --ignore-path .gitignore .",
    "lintfix": "eslint --fix --ext .js,.vue --ignore-path .gitignore .",
    "precommit": "npm run lint"
  },
  "dependencies": {
    "@nuxtjs/axios": "^5.3.6",
    "app-root-path": "^2.1.0",
    "body-parser": "^1.18.3",
    "cross-env": "^5.2.0",
    "express": "^4.16.3",
    "express-jwt": "^5.3.1",
    "express-rate-limit": "^3.3.2",
    "express-winston": "^3.0.1",
    "generate-password": "^1.4.1",
    "google-auth-library": "^2.0.1",
    "jsonwebtoken": "^8.4.0",
    "lodash": "^4.17.11",
    "mongoose": "^5.3.12",
    "mongoose-ref-validator": "^1.0.21",
    "mongoose-unique-validator": "^2.0.2",
    "mongoose-validator": "^2.1.0",
    "nodemailer": "^4.6.8",
    "nuxt": "^2.3.1",
    "passport": "^0.4.0",
    "passport-local": "^1.0.0",
    "passport-local-mongoose": "^5.0.1",
    "vuetify": "^1.3.9",
    "webpack-node-externals": "^1.7.2",
    "winston": "^3.1.0"
  },
  "devDependencies": {
    "babel-eslint": "^10.0.1",
    "eslint": "^4.0.0",
    "eslint-config-prettier": "^3.3.0",
    "eslint-loader": "^2.1.1",
    "eslint-plugin-prettier": "^3.0.0",
    "eslint-plugin-vue": "^4.7.1",
    "nodemon": "^1.18.6",
    "prettier": "^1.14.3",
    "stylus": "^0.54.5",
    "stylus-loader": "^3.0.2"
  }
}