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#327: Untangling XML with Pydantic

Published Mon, Mar 13, 2023, recorded Mon, Mar 13, 2023
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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.
  • 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 is super small

        import nox
        @nox.session(python=["3.8", "3.9", "3.10", "3.11", "3.12", "pypy3"])
        def test(session):
  "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.



Joke: Case of the Mondays

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