Library Service

Requirements:

1. Implement CRUD functionality for Books Service

• Initialize books app
• Add book model
• Implement serializer & views for all endpoints

2. Add permissions to Books Service

• Only admin users can create/update/delete books
• All users (even those not authenticated) should be able to list books
• Use JWT token authentication from users' service

3. Implement CRUD for Users Service

• Initialize users app
• Add user model with email
• Add JWT support
• For a better experience during working with the ModHeader Chrome extension - change the default Authorization header for JWT authentication to for example Authorize header. Take a look at the docs on how to deal with it.
• Implement serializer & views for all endpoints

4. Implement Borrowing List & Detail endpoint

• Initialize borrowings app
• Add borrowing model with constraints for borrow_date, expected_return_date, and actual_return_date.
• Implement a read serializer with detailed book info
• Implement list & detail endpoints

5. Implement Create Borrowing endpoint

• Implement create a serializer
• Validate book inventory is not 0
• Decrease inventory by 1 for book
• Attach the current user to the borrowing
• Implement and create an endpoint

6. Add filtering for the Borrowings List endpoint

• Make sure all non-admins can see only their borrowings
• Make sure borrowings are available only for authenticated users
• Add the is_active parameter for filtering by active borrowings (still not returned)
• Add the user_id parameter for admin users, so admin can see all users’ borrowings, if not specified, but if specified - only for concrete user

7. Implement return Borrowing functionality

• Make sure you cannot return borrowing twice
• Add 1 to book inventory on returning
• Add an endpoint for it

8. Implement the possibility of sending notifications on each Borrowing creation

• Set up a telegram chat for notifications posting in there
• Set up a telegram bot for sending notifications
• Investigate the sendMessage function interface in Telegram API
• Make sure all private data is private, and never enters the GitHub repo (you can use the python-dotenv package for simple working with .env files. Make sure to add the .env.sample file with the .env content skeleton)
• Create a helper for sending messages to the notifications chat through Telegram API
• Integrate sending notifications on new borrowing creation (provide info about this borrowing in the message)

9. Implement a daily-based function for checking borrowings overdue

• The function should filter all borrowings, which are overdue (expected_return_date is tomorrow or less, and the book is still not returned) and send a notification to the telegram chat about each overdue separately with detailed information
• It will be a scheduled task, and Django by default cannot do such tasks. To perform this task, you’ll have to use Django-Celery.
• If no borrowings are overdue for that day - send a “No borrowings overdue today!” notification.

Technologies to use:

1. Use Celery as task scheduler for check of overdue borrowings and sending push notification in Telegram Bot.
2. Python, Django ORM, PostgreSQL.
3. All endpoints should be documented via Swagger.

How to run:

• Copy .env_sample -> .env and populate with all required data
• docker-compose up --build
• Create admin user & Create schedule for check of overdue borrowings and sending push notification in Telegram Bot