index.js

const express = require('express')
const bodyParser = require('body-parser')
const app = express()
const dotenv = require('dotenv')
dotenv.config()

const db = require('./db')
const port = 3000

// Add headers
// https://stackoverflow.com/a/18311469
app.use(function (req, res, next) {
  // TODO: make this more dynamic and decide on a front end port (9090 for now)
  // Website you wish to allow to connect
  res.setHeader('Access-Control-Allow-Origin', 'http://localhost:9090')

  // Request methods you wish to allow
  res.setHeader('Access-Control-Allow-Methods', 'GET, POST, OPTIONS, PUT, PATCH, DELETE')

  // Request headers you wish to allow
  res.setHeader('Access-Control-Allow-Headers', 'X-Requested-With,content-type')

  // Set to true if you need the website to include cookies in the requests sent
  // res.setHeader('Access-Control-Allow-Credentials', true);

  // Pass to next layer of middleware
  next()
})

app.use(bodyParser.json())
app.use(
  bodyParser.urlencoded({
    extended: true
  })
)

app.get('/', (request, response) => {
  response.json({ info: 'Node.js, Express, and Postgres API' })
})

app.get('/users', db.getUsers)
app.get('/users/:id', db.getUserById)
app.post('/users', db.createUser)

app.listen(port, () => {
  console.log(`App running on port ${port}.`)
})