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Cowin Vaccine Tracker and AutoBooking bot

  • A bot to track available slots and book them automatically before any human around you does. :)

Features

  • Track upto 4 pincodes
  • Can track all pincodes/age group from Cowin website
  • Can download Certificate after vaccination
  • A status message to display your session time, beneficiaries you're booking for, snooze time and many more
  • User friendly and guiding commands in each message
  • Fast and instant walkthrough to guide you at each step
  • Snooze, to stop alerts for particular time without stopping the bot
  • Can track specific age group, vaccine, dose and pincode
  • You can view number of users on the bot from different states and cities.
  • Automatic Slot booking
  • Has Seperate bot's login panel to authenticate with cowin

Some internal code magic

  • Has an API to build an autologin application. (Incomplete and abandoned)
  • Has pincode and District caching
  • Automatically divides slot tracking by just providing proxies in proxies.txt (Calculated from cowin's rate limit, But since govt removed rate limit on public API, Its deprecated.)
  • Can bypass cache (Has a seperate description below.)
  • Has seperate login panel to avoid authentication rate limiting from same IP, Instead a browser window will open and requests will be sent from user's device and token will be shared with bot after authentication.
  • Cowin-like 180sec otp limiting.
  • All the Phone, Pincode, State and other inputs are validated before proceeding further.
  • A cron job to wipe server logs, Backup existing database and clear cache every midnight
  • Admin restricted commands to broadcast messages to users, Check user availability, Logged in users, adjust sleeptime of tracker and tracker live status informer
  • Snooze timestamp is stored in database and every slot availability message is checked before sending to user.
  • A cron job to reset otp count of all users every night, Reason: Cowin bans account for 24hours if you requested more than 50 otp in 24 hours.

Depreacation

  • Before knowing about Cache bypassing, I used user's token to fetch data from private API endpoint. For eg. There are 40-50 users booking vaccine slots using the bot, So during that I took any random valid auth token and requested on private API endpoint to fetch realtime data. But later I discovered cache bypass and reverted this logic.

How I bypassed cache on public API

  • The cowin server uses GoLang in backend and uses a module called dateparse This module can detect many date formats without even specifying.

    • So passing a date 26/11/2021 or 26/11/21 or 26-11-21 or even with zeros 06/04/2021 can be also written as 6/4/21 and so on
    • I created a date obfuscator present in wrapper.js with function getToday
    • The caching service uses, AWS. Which allowed cowin to cache request for few minutes. Now in this case those few minutes are cruicial.
    • I examined the request and the only thing was API path + query params. And a reponse header x-amzn-remapped-date which shows when the particular data was last cached on AWS servers.
  • After using the date obfuscator that I had created, It successfully bypassed caching (you can check x-amzn-remapped-date)

Before you criticize my code... xD

I know the coding structure is trash, I didn't follow the time complexity properly. But the code is not repetitive. But after all... I built this within a month, Moreover I released this bot in just 3 days after 18+ vaccination started. Since then I managed my worklife, real life and maintained this bot as well. So please bear with the code quality. :)

Here are some appreciations I got


Thanks for using and supporting. ❤️ This will remain my bestest work so far.

License

© Swapnil Soni (MIT) (If you plan to copy the code then link the credits in your bot with a link to my github repo.)