demo-distributed-discounts

• demo-distributed-discounts
  • Installation
    • With Docker Compose and Poetry
  • Development and testing
  • TODO

Homework about distributed systems.

More documentation in DOCS.md

Installation

With Docker Compose and Poetry

• Required software

  • Python 3.9 or higher
  • Docker Desktop
  • Python Poetry

• Start the app for development (with auto reload enabled)

  docker compose up
  

• After application start, database is refreshed with test data from scripts/initial_data.py

  • Available campaign_id - 1 and 2
  • Generated 10'000 discount codes for each campaign.

• Start the app with gunicorn for concurrency testing (production mode)

  docker compose -f docker-compose.gunicorn.yml up
  

• (optional) To run auto tests with pytest, additionally install dependencies locally with Poetry

  • Update global Python packages

  python -m pip install -U pip wheel setuptools
  

  • Install dependencies

  poetry install
  

  • Activate Python virtual environment

  poetry shell
  

  • Install pre-commit hooks

  pre-commit install
  

Development and testing

• Helper commands from scripts/dev_commands.py

poetry run format/lint/test/test_cov_term/test_cov_html/test_ci

• Run all hooks at once

poetry run hooks

TODO

• Documentation
• How to start the app
• Presentation
• Fetch a discount code
  • POST, 201
  • GET 200
  • is_used flag
  • 404 if campaign does not exist
  • Authentication with fake JWT like token
  • Decouple business logic from Flask route
  • SELECT FOR UPDATE SKIP LOCKED for concurrent selects
  • Send callback to the brand that code has been created
• Generate a discount code. Brand wants to create X number of discount codes
  • Generate job ID and simulate as if job was placed to the queue
  • Create discounts codes asynchronously
  • Route for polling job status <-- not doing now