Routes

A route is a code that represents an HTTP action, (GET, POST, PUT, DELETE). It has a URL endpoint, and a function that is used to handle when that endpoint is accessed.

We use postman to test these endpoints. Accessing these endpoints prior to setting up the code will return a 404 NOT FOUND - a html response.

Lets look at the code for a GET request at greeting endpoint.
We call the get method on the app object, passing in two arguments

• The Endpoint.
• The function to handle this endpoint. It takes in a request and a response object as parameters.

app.get('/api/greeting', (req, res) => {
    res.send('Hello there, Welcome!')
} )

Now, if we access the route, we get a 200 OK status and the String "Hello there...." is returned.

Usually we are gonna return JSON data. So the above code could be changed to

app.get('/api/greeting', (req, res) => {
    res.status(200).json({message:'Hello there, Welcome!'})
} )

We also set the status, although not necessary. Now we respond with a JSON object and the content type of the response changes from html to application/json. Even though we didn't add quotes on the key "message", it get parsed into JSON.

---

Now we don't wanna clutter our server.js file with all these routes. So we clean it up.

In the backend folder, we create a folder called 'routes' and in it we create file greetRoutes.js. So basically each resource in API will have it's own route file.

Folder structure : backend/routes/greetRoutes.js

Now to use the express router, we are gonna first bring the express into this file.

#greetRoutes.js

const express = require('express');
const router = express.Router();

router.get('/', (req, res) => {
    res.status(200).json({message:'Hello there, Welcome!'})
} )

module.exports = router

and inside server.js

#server.js
....
app.use('/api/greeting', require('./routes/greetRoutes.js');
...

So now, if we hit /api/greeting, it's gonna look into the Route file, and all we needed was a / because /api/greeting is already specified.

Similarly, we can create other routes for POST, PUT, DELETE.
Some of them will require a :id in the endpoint part so that they access the right data point. router.put('/:id', (req,res) => {....})

Next up, Controllers. Again to clear the clutter!