Creating GET and POST Express routes

#

📝 This lesson's quiz can be found - here.
🗒️ Solutions for This lesson's quiz can be found - here.
📃 Grab a cheatsheet that summarizes creating a simple GET and POST route with Express - here.

With our mock listings array defined, we'll attempt to have our Express server give us the capability to GET and POST changes to this mock data array.

Like we've seen for the index route (/) in the src/index.ts file, Express gives us the capability to creates routes which refer to how different endpoints respond to client requests. We're going to create two new separate routes:

• A /listings route with which we can retrieve the listings collection.
• A /delete-listing route with which we can delete a specified listing.

Get listings

#

To GET the listings information in an Express route, we can do just like what we've done when we sent the 'hello world' message for the index route. We'll first import the listings array in our src/index.ts file.

import { listings } from "./listings";

Then use the app.get() method to create a new /listings route that is to simply return the listings array.

app.get("/listings", (_req, res) => {
  res.send(listings);
});

With the server being run, if we head to the browser and navigate to the /listings route, we'll be presented with our mock listings data array.

We're using the JSON Viewer Chrome Extension to humanize this data and make it more readable.

Delete a listing

#

We'll now create functionality to help delete a listing from our mock data.

In a standard REST API, the GET method is often used to request data. Though many other methods exist, we'll use the POST method to specify a route that can have data be sent to the server to conduct an action. In this case, we'll look to have the id of a listing be passed in which will be used to delete that particular listing. For our server to access the data in our POST request, we'll install a middleware to help parse the request body. We'll use the popular bodyParser library which can be installed alongside its type declaration file.