Python Bytes

Topics covered in this episode:

• 6 ways to improve the architecture of your Python project (using import-linter)
• Mountaineer
• Why Python's Integer Division Floors
• Hatchet
• Extras
• Joke

About the show

Sponsored by ScoutAPM: pythonbytes.fm/scout

Connect with the hosts

• Michael: @mkennedy@fosstodon.org
• Brian: @brianokken@fosstodon.org
• Show: @pythonbytes@fosstodon.org

Join us on YouTube at pythonbytes.fm/live to be part of the audience. Usually Tuesdays at 11am PT. Older video versions available there too.

Brian #1: 6 ways to improve the architecture of your Python project (using import-linter)

• Piglei
• Using import-linter to
  • define architectural layers
  • check to make sure imports don’t violate (import from upper layers)
  • can also check for more contracts, such as
    • forbidden - disallow a specific from/to import
    • independence - list of modules that shouldn’t import from each other
• Fixing violations
  • a process introduced to set exceptions for each violation in a config file
  • then fix violations 1 at a time (nice approach)
  • use the whole team if you can
• Common methods for fixing dependency issues
  • Merging and splitting modules
  • Dependency Injection, including using protocols to keep type hints without the need to import just for types
  • Use simpler dependency types
  • Delaying function implementations
    • module global methods set by caller, or adding a simple plugin/callback system
  • Configuration driven
    • Setting import statements in a config file and using import_string() at runtime
  • Replace function calls with event-driven approaches

Michael #2: Mountaineer

• Mountaineer is a batteries-included web framework for Python and React.
• Mountaineer focuses on developer productivity above all else, with production speed a close second.
  • ???? Typehints up and down the stack: frontend, backend, and database
  • ????️ Trivially easy client[HTML_REMOVED]server communication, data binding, and function calling
  • ???? Optimized server rendering for better accessibility and SEO
  • ???? Static analysis of web pages for strong validation: link validity, data access, etc.
  • ???? Skip the API or Node.js server just to serve frontend clients

Brian #3: Why Python's Integer Division Floors

• Guido van Rossum
• Integer division always floors (toward negative infinity) instead of truncating. (C truncates)
• 5//2 → 2
• -5//2 → -3
• 5//-2 → -3
• Reason,
  • For nice mathematical relationships with // and % (modulo).
  • a//b = quotient (q), a%b = remainder (r)
  • such that b*q + r = a, and 0 <= r < b
    • This works for both positive and negative a values
    • For negative b, the second rule has to change to 0 >= r > b
• If you truncate (like C does), you have to use abs(r) for the first rule to work.
• Theory of why C doesn’t do it this way: Probably a hardware limitation at the time when C was designed, due to “sign + magnitude” integers instead of modern two’s compliment integers.

Michael #4: Hatchet

• Hatchet is a distributed, fault-tolerant task queue which replaces traditional message brokers and pub/sub systems.
• It’s built to solve problems like concurrency, fairness, and durability
• Concurrency, Fairness, and Rate limiting: Enable FIFO, LIFO, Round Robin, and Priority Queues with built-in strategies to avoid common pitfalls.
• Architected for Resiliency: Customizable retry policies and built-in error handling to recover from transient failures.

Extras

Brian:

• Charlie Marsh on uv in PythonTest episode 216

Michael:

• Build An Audio AI App Course [free!]
• Rock Solid Python with Python Typing Course
• Coolio

Joke: Breaking Prod