Coding Challenge: Building REST API

Problem

You have implemented a flask-based REST API server that stores a variable serverData. The contents of this data do not change very frequently so you want to enable caching using ETag. The server code given below works fine without using caching and returns the content every time, even when it is not changed.

Your task is to implement ETag in the following server so that it sends 304 Not Modified on every GET request if the ETag provided is not updated. However, it should send the updated value otherwise and send the new Etag to the clients.

After implementing Etag functionality, run http GET http://127.0.0.1:5000 If-None-Match:"<your_etag>" to see the 304 Not Modified response. Try to change the serverData using PUT and then check if it returns updated content.

To run the following application, run the command python etag-test.py. It will start the flask-based HTTP server. Then, open another terminal, and contact the server using command http HEAD http://127.0.0.1:5000. Run http PUT http://127.0.0.1:5000 serverData="New data" to update the serverData variable.