This project aims to check availability of Covid vaccine slots in a neighbourhood and notify subscribers via email (preview) when it is available. This is a serverless and stateless code aimed to be running on google app script.

This repository is no longer actively maintained and missing features such as unsubscribe will not be implemented. You can check out this website which effectively solves the same problem.

Initially I planned to use Node JS as backend service for this project which would have worked fine but I would need to host it and maintain a database for it. Google sheets were enought for me as a database and not having to pay for hosting services for this project sounded appealing so I decided to used it as a backend service.

Initially I thought API fetch was not working because of incorrect request headers being sent to server and I spent way too much time trying to fix it as exaclty same request was working from postman in my local development environment. After hours of trial and error I managed to isolate the problem and found that firewall at cowin website is blocking all requests which originated outside India and returned this. Since this project was intended to run at google servers and I can't control the location of those servers, there is no obvious way for me to make it work.

Many parts of this code work perfectly such as accepting responses from user and sending dynamically generated emails on a time event triggered function. They can be used to learn and get a deeper insignt into Google app script and develop skills. All code in this repo is freely available to everyone and can be used in different pojects.

Making this app was a great learning outcome for me as I not only got to work on a real world problem but had to do it in a small time frame to develop it. This is first time I used debugger fucntion by setting breakpoints and it was life changing for me. But, the most important lesson of all which I learnt was to test core functions of your app early in development stages so that you'll know this solution is actually viable.

This project uses MIT License.