#327: Untangling XML with Pydantic

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

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Michael #1: pydantic-xml extension

• via Ilan
• Recall untangle. How about some pydantic in the mix?
• pydantic-xml is a pydantic extension providing model fields xml binding and xml serialization / deserialization. It is closely integrated with pydantic which means it supports most of its features.

Brian #2: How virtual environments work

• Brett Cannon
• This should be required reading for anyone learning Python.
  • Maybe right after “Hello World” and right before “My first pytest test”, approximately.
• Some history of environments
  • Back in the day, there was global and your directory.
• How environments work
  • structure: bin, include, and lib
  • pyvenv.cfg configuration file
• How Python uses virtual environments
• What activation does, and that it’s optional.
  • Yes, activation is optional.
• A new project called microvenv that helps VS Code.
  • Mostly to fix the “Debian doesn’t ship python3 with venv” problem.
  • It doesn’t include script activation stuff
  • It’s super small, less than 100 lines of code, in one file.

Michael #3: DbDeclare

• Declarative layer for your database.
• https://raaidarshad.github.io/dbdeclare/guide/controller/#example
• Sent in by creator raaid
• DbDeclare is a Python package that helps you create and manage entities in your database cluster, like databases, roles, access control, and (eventually) more.
• It aims to fill the gap between SQLAlchemy (SQLA) and infrastructure as code (IaC).
• You can:
  • Declare desired state in Python
  • Avoid maintaining raw SQL
  • Tightly integrate your databases, roles, access control, and more with your tables
• Migrations like alembic coming too.

Brian #4: Testing multiple Python versions with nox and pyenv

• Seth Michael Larson
• This is a cool “what to do first” with nox.
• Specifically, how to use it to run pytest against your project on multiple versions of Python.

• Example noxfile.py is super small

      import nox
  
      @nox.session(python=["3.8", "3.9", "3.10", "3.11", "3.12", "pypy3"])
      def test(session):
          session.install(".")
          session.install("-rdev-requirements.txt")
          session.run("pytest", "tests/")
  

• How to run everything, nox or nox -s test.

• How to run single sessions, nox -s test-311 for just Python 3.11
• Also how to get this to work with pyenv.
  • pyenv global 3.8 3.9 3.10 3.11 3.12-dev
• This reminds me that I keep meaning to write a workflow comparison post about nox and tox.

Extras

Michael:

• GitHub makes 2FA mandatory next week for active developers
• New adventure bike [image 1, image 2].
  • Who’s got good ideas for where to ride in the PNW?
  • Wondering why I got it, here’s a fun video.

Joke: Case of the Mondays