Posts tagged: python

Today I learned how to use AliasChoices with pydantic settings to setup common aliases for the same field. I’m bad about remembering these things, and hate looking up the docs. I like things to be intuitive and just do the thing I want it to do. Especially when they get configured through something like yaml and do not have a direct lsp look up right from my editor. I figured out how to support what might be common aliases for a storage directory. These can be set up as environment variables and used by config.

I often want to run an s3 sync in an isolated environment, I don’t want to set any environment variables, I don’t want anything secret in my history, and I don’t want to change my dotenv into something that exports variables, I just want s3 sync to work. dotenv run is the tool that I’ve been using for this, and this uv one liner lets it run fully isolated from the project.

uv tool run --from 'python-dotenv[cli]' dotenv run -- uv tool run --from awscli aws s3 sync s3://bucket data

multi-line #

same thing formatted for readability

uv tool run \ --from 'python-dotenv[cli]' \ dotenv run -- \ uv tool run \ --from awscli \ aws s3 sync s3://dropper data

There are probably 10 ways to skin this cat, but this is what I did, if you have a better way let me know, I’ll link you below.

FastAPI is a modern and efficient web framework for Python, built on top of the Starlette web framework, and pydantic for data validation and serialization.

FastAPI is a modern, fast (high-performance), web framework for building APIs with Python based on standard Python type hints.

The key features are:

The +5 point increase for FastAPI is one of the most significant shifts in the web framework space. This signals a strong trend towards using Python for building performant APIs and reflects the overall strength of the Python ecosystem.

FastAPI.">Starlette has a head request that works right along side your get requests. This morning I fiddled around with custom routes for GET and HEAD, but had to manually set some things about the file, and was still missing e-tag in the end. Turns out as a developer you can just add a head route to your get routes and starlette will strip the content for you, while preserving all of those good headers that fastapi FileResponse created automatically for you.

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anthony has some of the best python highlight videos each year. This might be a good sign, but each year there seems to be less and less that I am chomping at the bit to get to. I thought the remote debugger looked every interesting, his use case for babi seemed very interesting. I wonder what textual would look like built in a 3.14 world, would it still have built its own debugger/console?

uv tool run --python=3.14 babi

Without a process flag you need sudo permissions to attach a pdb debugger similar to gdb.

PEP 735 describes dependency groups as sets of optional dependencies that are not shipped with the package but intended for development purposes.

The PEP includes an example for groups that include test, docs, typing, and a combo typing-test.

[dependency-groups] test = ["pytest", "coverage"] docs = ["sphinx", "sphinx-rtd-theme"] typing = ["mypy", "types-requests"] typing-test = [{include-group = "typing"}, {include-group = "test"}, "useful-types"]

This is implemented in uv and can be used by several of their commands.

uv sync --group test uv run --group test uv add --group test pytest uv remove --group test pytest uv export --group test uv tree --group test

Dependency Groups are not Extras #

The docs describe extras as being intended to ship with the application and dependency groups intended for development. The spec allows both to exist with the same name, but care should be taken as tools may have different implementations.

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I smell a dependency to python-dotenv dying in my workflow. I originally read the title of the post and thought, “I know how to manage .env and almost skipped it”. I’m leaning more and more on uv run these days, so this should just go in my [[ just file ]] to make it easy to run.

I’ve been leaning on lazy-self-installing-python-scripts more and more, but I did not realize how much tooling that uv gives you to help manage your scripts.

uv init --script up uv add --script up typer rich uv remove --script up rich sed -i '1i #!/usr/bin/env -S uv run --script' up chmod +x up ./up

The result is a script that looks like this, its executable as what looks like regular command in your shell.

I have a couple of use cases for simple qr codes in python coming up. One is for blog posts, the other is for auth into a new server application logged to a terminal. I tried the qrcode library and it does not look as nice to me and I found pyqrcode to be quite nice.

import pyqrcode url = pyqrcode.create('https://waylonwalker.com/qr-codes-in-python') url.svg('qr-codes-in-python.svg', scale=8) print(url.terminal(quiet_zone=1)) url.svg('qr-codes-in-python.svg', scale=12) url.svg('qr-codes-in-python.svg', omithw=True) # width is controlled by the container url.svg('qr-codes-in-python.svg', omithw=True, module_color='#ffd119') url.svg('qr-codes-in-python.svg',...