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Uv: Running a script with dependencies

docs.astral.sh

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Re: Uv: Running a script with dependencies

#11

Post by meander_water »

simonw wrote: post #4

The "declaring script dependencies" thing is incredibly useful: https://docs.astral.sh/uv/guides/scripts/#declaring-script-d... # /// script # dependencies = [ # "requests Save that as script.py and you can use "uv run script.py" to run it with the specified dependencies, magically installed into a temporary virtual environment without you having to think about them at all. It's an implementation of Python PEP 723: h…

PEP723 is also supported by pipx and hatch, even though uv is (deservedly) getting all the attention these days.

Others like pip-tools have support in the roadmap (https://github.com/jazzband/pip-tools/issues/2027)

Re: Uv: Running a script with dependencies

#12

Post by tayloramurphy »

minimaxir wrote: post #5
simonw wrote: post #4

The "declaring script dependencies" thing is incredibly useful: https://docs.astral.sh/uv/guides/scripts/#declaring-script-d... # /// script # dependencies = [ # "requests Save that as script.py and you can use "uv run script.py" to run it with the specified dependencies, magically installed into a temporary virtual environment without you having to think about them at all. It's an implementation of Python PEP 723: h…

I thought that was a heart emoticon next to requests, for a second.

I mean, who doesn't love requests?

Re: Uv: Running a script with dependencies

#13

Post by alkh »

gopalv wrote: post #2

This is my absolute favourite uv features and the reason I switched to uv. I have a bunch of scripts in my git-hooks which have dependencies which I don't want in my main venv. #!/usr/bin/env -S uv run --script --python 3.13 This single feature meant that I could use the dependencies without making its own venv, but just include "brew install uv" as instructions to the devs.

If I may interject, does anyone have any idea why the `-S` flag is required? Testing this out on my machine with a BSD env, `/usr/bin/env -S uv run --python 3.11 python` and `/usr/bin/env uv run --python 3.11 python` do the same thing (launch a Python interactive shell). Man page for env doesn't clarify a lot to me, as the end result still seems to be the same("Split apart the given string into multiple strings, and process each of the resulting strings as separate arguments to the env utility...")

Re: Uv: Running a script with dependencies

#14

Post by AceJohnny2 »

Note that this only works for single-file scripts.

If you have a project with modules, and you'd like a module to declare its dependencies, this won't work. uv will only get those dependencies declared in the invoked file.

For a multi-file project, you must have a `pyproject.toml`, see https://docs.astral.sh/uv/guides/projects/#managing-dependen...

In both cases, the script/project writer can use `uv add `, just in the single-file case they must add `--script`.

Re: Uv: Running a script with dependencies

#15

Post by Hello71 »

alkh wrote: post #13
gopalv wrote: post #2

This is my absolute favourite uv features and the reason I switched to uv. I have a bunch of scripts in my git-hooks which have dependencies which I don't want in my main venv. #!/usr/bin/env -S uv run --script --python 3.13 This single feature meant that I could use the dependencies without making its own venv, but just include "brew install uv" as instructions to the devs.

If I may interject, does anyone have any idea why the `-S` flag is required? Testing this out on my machine with a BSD env, `/usr/bin/env -S uv run --python 3.11 python` and `/usr/bin/env uv run --python 3.11 python` do the same thing (launch a Python interactive shell). Man page for env doesn't clarify a lot to me, as the end result still seems to be the same("Split apart the given string into multiple strings, and…

https://en.wikipedia.org/wiki/Shebang_(Unix)#Argument_splitt...

Re: Uv: Running a script with dependencies

#16

Post by Skunkleton »

alkh wrote: post #13
gopalv wrote: post #2

This is my absolute favourite uv features and the reason I switched to uv. I have a bunch of scripts in my git-hooks which have dependencies which I don't want in my main venv. #!/usr/bin/env -S uv run --script --python 3.13 This single feature meant that I could use the dependencies without making its own venv, but just include "brew install uv" as instructions to the devs.

If I may interject, does anyone have any idea why the `-S` flag is required? Testing this out on my machine with a BSD env, `/usr/bin/env -S uv run --python 3.11 python` and `/usr/bin/env uv run --python 3.11 python` do the same thing (launch a Python interactive shell). Man page for env doesn't clarify a lot to me, as the end result still seems to be the same("Split apart the given string into multiple strings, and…

Its needed on my ubuntu 24.04 system

  $ cat test.sh
  #!/usr/bin/env bash -c "echo hello"
  $ ./test.sh
  /usr/bin/env: ‘bash -c "echo hello"’: No such file or directory
  /usr/bin/env: use -[v]S to pass options in shebang lines
  $ ./test.sh # with -S
  hello

Re: Uv: Running a script with dependencies

#17

Post by alkh »

Hello71 wrote: post #15
alkh wrote: post #13

Earlier quoted context omitted.

If I may interject, does anyone have any idea why the `-S` flag is required? Testing this out on my machine with a BSD env, `/usr/bin/env -S uv run --python 3.11 python` and `/usr/bin/env uv run --python 3.11 python` do the same thing (launch a Python interactive shell). Man page for env doesn't clarify a lot to me, as the end result still seems to be the same("Split apart the given string into multiple strings, and…

https://en.wikipedia.org/wiki/Shebang_(Unix)#Argument_splitt...

Thanks, but the main question is how come the behaviour is still the same whether you pass the flag or not? I would get it if it just failed without "-S" but it works as intended. I am wondering if this is cause I might not be using the GNU version of env, so this is less relevant? Edit: looks to be the version thing indeed, this doesn't work for someone on Ubuntu

Re: Uv: Running a script with dependencies

#18

Post by alkh »

Skunkleton wrote: post #16
alkh wrote: post #13

Earlier quoted context omitted.

If I may interject, does anyone have any idea why the `-S` flag is required? Testing this out on my machine with a BSD env, `/usr/bin/env -S uv run --python 3.11 python` and `/usr/bin/env uv run --python 3.11 python` do the same thing (launch a Python interactive shell). Man page for env doesn't clarify a lot to me, as the end result still seems to be the same("Split apart the given string into multiple strings, and…

Its needed on my ubuntu 24.04 system $ cat test.sh #!/usr/bin/env bash -c "echo hello" $ ./test.sh /usr/bin/env: ‘bash -c "echo hello"’: No such file or directory /usr/bin/env: use -[v]S to pass options in shebang lines $ ./test.sh # with -S hello

Interesting, I guess it is indeed a BSD thing, cause this works for me with or without '-S' on Mac

Re: Uv: Running a script with dependencies

#19

Post by heisenzombie »

Quick plug here for a simple Jupyter kernel I created:

https://github.com/tobinjones/uvkernel

It’s a pretty minimal wrapper around “uv” and “iPython” to provide the functionality from the article, but for Jupyter notebooks. It’s similar to other projects, but I think my implementation is the least intrusive and a good “citizen” of the Jupyter ecosystem.

There’s also this work-in-progress:

https://github.com/tobinjones/pep723widget

Which provides a companion Jupyter plugin to manage the embedded script dependencies of noteboooks with a UI. Warning — this one is partially vibe-coded and very early days.

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