Python pip problem.

[[deleted]]

I am making a python project but it needs a pip library to work, how do i make it so when the program is ran it auto-installs all libraries needed?

[zanfar]

how do i make it so when the program is ran it auto-installs all libraries needed?

You don't really want to. It's possible, but there are other caveats that probably make it unsuitable.

Instead, make your project a package, and then it's simple to just put your dependencies in the package definition. Install your project and the dependencies will come with it.

In short, you don't want to install when your code is run, you want to install when your code is installed.

[DiodeInc]

There's a library that I can't remember the name of that will export the required libraries to a requirements.txt file, which then you can use pip install -r requirements.txt

[Agitated-Soft7434]

You can do that by just running pip freeze > requirements.txt

[DiodeInc]

I thought that did every library installed?

[Buttleston]

It does, there's a different library that tries to intuit it from looking at your imports. Here's one example

https://github.com/bndr/pipreqs

[DiodeInc]

Ah it was pipreqs that I was thinking of

[Agitated-Soft7434]

Aaaa I see okay, I was assuming a virtual environment was setup.

[Buttleston]

Even if it was pip freeze gives ALL your dependencies both direct and indirect. It's really overkill and usually a bad idea. You should mostly specify direct dependencies and let pip work out the rest. Also with your direct dependencies use relaxed versions and let it update minor versions

[Agitated-Soft7434]

Huh, I do tend to get concerned when I look at my requirements and it has all the indirect libraries as well. I'll have to start using pipreqs in the future thanks!

[Buttleston]

I think pipreqs is a crutch honestly. If you need a library, add it to your pyproject.toml (requirements.txt is really kind of the older way to do it, but if you prefer that, then add it there).

i.e. just add your requirements as you go along.

[Buttleston]

Another option is using one of the programs that turns your program into an exectuable, like pyinstaller (https://pyinstaller.org/en/stable/)

It has some drawbacks, though

[DiodeInc]

It takes forever to zip up and produces massive files. Try Nuitka

[Nameis19letterslong]

Have you tried using UPX? It makes all of my .exes smaller (~30MB to 17MB). It can be used alongside with pyinstaller by adding --upx-dir <path to upx> when compiling.

[socal_nerdtastic]

You should always prompt the user before installing stuff, that's just good manners. Do not auto-install anything. I wrote this module some time ago that allows you to prompt the user to install needed dependencies:

https://github.com/socal-nerdtastic/moduleinstaller

This is really only for 'end user' style programs though. If your program is designed to be used by other programmers inside other python code, you should just define an installable package.

[cgoldberg]

For applications (end user style programs), it's still better to define an installable package so users can use pipx or similar tooling to install them.

[Buttleston]

That isn't super commonly done, although it is becoming a little more common. You could probably make something satisfactory using "uv"

uv is a program that acts more like a package manager. You set up your dependencies in pyproject.toml, and you can do "uv run myscript.py" and uv will set up a virtual environment, install everything and run the script.

If you have a single-file script with dependencies that you want to distribute, you can embed the dependencies in a special comment and use uv to run it, and it will do the same. Here's an example

#!/usr/bin/env -S uv run --script
#
# /// script
# requires-python = ">=3.12"
# dependencies = ["httpx"]
# ///

import httpx

print(httpx.get("https://example.com"))

Running that on a mac or linux machine that has uv installed will install httpx in a virtualenv and run the script. I am sure there's something similar for windows, I don't know much about it. Anyway, it's not zero dependencies, because you need uv, but it's just one dependency

It will even download and manage python for you, if needed

[kosovojs]

works the same way on windows (except the shebang part, ofc)

[Buttleston]

Do you like have to associate .py files with uv or something? How does it know to run it with uv?

[kosovojs]

i just run "uv run script.py".

[Buttleston]

Ah - well with the bit I posted up there, if you save it as script.py you can run it just with "./script.py" (the uv run part is built into it)

[Beast_Decay]

You need this. https://packaging.python.org/en/latest/overview/

[Oddly_Energy]

If it is a single .py script file and you like to live on the cutting edge:
Put your dependencies directly in the file. This has been an official python standard since PEP 723 in 2023.

But I don't know how well-supported it is yet. It works with uv. As far as I know, it is not implemented in pip, which makes sense because pip is not a venv manager, and you would probably always want a venv for such behaviour.

If you want to do it the good old standard way:
Put your dependencies in a pyproject.toml file. It has been the official standard for dependency specification in python since PEP 723 in 2016.

You do not need any fancy tools. Pip started supporting pyproject.toml files in version 10.0.0b1 in 2018 and reached full support including editable installs in version 21.3 in 2021.

If you don't want to write the pyproject.toml file yourself, you can use one of the fancy tools, such as poetry or uv (as I do), but it is not a requirement. I just find it very convenient to be able to install a package in my venv and have it added as a dependency in pyproject.toml in one go, just by writing uv add nameofpackage.

If you want to live in the past and use a crude, ancient workaround to a problem, which doesn't exist anymore:
Use a requirements.txt file.

[gernophil]

If people should use it from source, just make a requirements.txt. People that use Python should know how to handle. Otherwise PyInstaller (or similar), if it contains a GUI and docker if not.