Architecture

app.js

We require our modules and configurations to build the server and the app. Then we attach our features (from other folders) to the server and the app :

• Api routes in the API folder.
• Front-End routes in the FRONT folder.
• Websocket routes in the WS folder.

API

Our API is build upon 3 main components :

• routes
• controllers (middlewares)
• models

routes

Routes are just endpoints, we create them with Express Router. Routers can be chained :

const router1 = Express.router();
const router2 = Express.router();

router1.use('/router2', router2);
router2.route('/myroute') // here : /router2/myroute
    .get(...)
    .post(...)
    .put(...);

controllers

Controllers are middlewares.

Each route takes one middleware or more as parameter. In each middleware, we call the next() function to go to the next middleware :

router.route('/something')
    .get(middleware1, middleware2, middleware3, middlewareEnd);
//          \            \            \             \
//           \_ next()    \_ next()    \_ next()     \_ res.send()

models

The models are just javascript objects or functions that communicates with your database. They are the only components that have the right to interact with your DB. So, say you have a middleware that gets the current user informations in the database, it will have to call a method from your user model that will return the current user : userModel.getCurrentUser(token).

Illustration

Getting started

sudo -u postgres psql
sudo apt-get install postgresql

CREATE USER xxx WITH PASSWORD 'xxx';
CREATE DATABASE xxx;
GRANT ALL PRIVILEGES ON DATABASE xxx to xxx;

CREATE TABLE users(
   firstname VARCHAR,
   lastname VARCHAR,
   email VARCHAR,
   PRIMARY KEY( email )
);

Knex.js

Create a migration

   knex migrate:make xxx