old_contents: const express = require('express');
  const router = express.Router();
  const Authors = require('../database/db').Authors
  const Genres = require('../database/db').Genres
  const Books = require('../database/db').Books
  
  /* GET home page. */
  router.get('/', function(req, res, next) {
    let random = []
    for (var i = 0; i < 12; i++) {
      let id = Math.floor(Math.random()*1000)
      random.push(Books.get(id))
    }
    Promise.all(random)
    .then( result => {
      res.render('index', { title: 'Express', items: result })
    })
  });
  
  router.get('/details/:id', function(req, res, next) {
    const id = req.params.id
    Books.get(id).then((book) => {
      res.render('details', { book : book })
    })
  });
  
  router.post('/delete/:id', function(req, res, next){
    const id = req.params.id
    (id)
    Books.delete(id)
    .then( deletedBook => {
      ('deletedBook:',deletedBook)
      res.render('deletedBook',{ deletedBook : deletedBook })
    })
  });
  
  router.post('/search', function(req, res, next) {
    const searchInput = req.body.searchInput
    const parsedSearchInput = '%'+searchInput.replace(/\s+/,'%')+'%'
    Books.search(parsedSearchInput)
    .then(parsedSearchInputResults => {
      let bookSearchResultsDatabaseCalls = []
      const idArray = parsedSearchInputResults.map(parsedSearchInputResult => parsedSearchInputResult.id)
      (idArray)
      idArray.forEach(id => bookSearchResultsDatabaseCalls.push(Books.get(id)))
      return Promise.all(bookSearchResultsDatabaseCalls)
    })
      .then( databaseCallsResults => {
        res.render('index', { items: databaseCallsResults })
    })
  });
  
  module.exports = router;
  
new_contents: const express = require('express');
  const router = express.Router();
  const Authors = require('../database/db').Authors
  const Genres = require('../database/db').Genres
  const Books = require('../database/db').Books
  
  /* GET home page. */
  router.get('/', function(req, res, next) {
    let random = []
    for (var i = 0; i < 12; i++) {
      let id = Math.floor(Math.random()*1000)
      random.push(Books.get(id))
    }
    Promise.all(random)
    .then( result => {
      res.render('index', { title: 'Express', items: result })
    })
  });
  
  router.get('/details/:id', function(req, res, next) {
    const id = req.params.id
    Books.get(id).then((book) => {
      res.render('details', { book : book })
    })
  });
  
  router.post('/delete/:id', function(req, res, next){
    const id = req.params.id
    (id)
    Books.delete(id)
    .then( deletedBook => {
      ('deletedBook:',deletedBook)
      res.render('deletedBook',{ deletedBook : deletedBook })
    })
  });
  
  router.post('/search', function(req, res, next) {
    const searchInput = req.body.searchInput
    const parsedSearchInput = '%'+searchInput.replace(/\s+/,'%')+'%'
    Books.search(parsedSearchInput)
    .then(parsedSearchInputResults => {
      let bookSearchResultsDatabaseCalls = []
      const idArray = parsedSearchInputResults.map(parsedSearchInputResult => parsedSearchInputResult.id)
      idArray.forEach(id => bookSearchResultsDatabaseCalls.push(Books.get(id)))
      return Promise.all(bookSearchResultsDatabaseCalls)
    })
      .then( databaseCallsResults => {
        res.render('index', { items: databaseCallsResults })
    })
  });
  
  module.exports = router;
  
subject: Fix error in search route