PyO3/pyo3

Expose a way to access the `PYO3_CONFIG_FILE` values

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#2,033 opened on Nov 29, 2021

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 (2 comments) (0 reactions) (0 assignees)Rust (10,152 stars) (668 forks)batch import
Good First Issueneeds-implementer

Description

Some users have specific use cases where they would benefit from being able to access the PYO3_CONFIG_FILE values in some form from the pyo3 crate.

I generally wouldn't advise this, as a lot of these config files (such as library path) are unique to the build environment so wouldn't have any useful meaning in binaries intended to be deployed on other systems.

See original comment from #2000 below.

If anyone has need for this, I'm happy to help review designs and implementation.

It would be nice to have access to the library path from PYO3_CONFIG (or all values) but that is not a problem for me.

E.g. it could be based off the PYO3_CONFIG build mechanism - maybe we could have pyo3_config_var!("lib_path"). Or maybe just pyo3_lib_path!(). I'm open to hearing ideas on what's better.

An alternative could be a module filled with many const values, similar to what built does.

Originally posted by @jonasbb in https://github.com/PyO3/pyo3/issues/2000#issuecomment-979985994

Contributor guide

Tech stack
rustpython
Domain
developer experiencetooling
Issue type
feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
4
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-2 days
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
needs investigation
Prerequisites
understanding of Rust macrosfamiliarity with PyO3 build systemknowledge of config file parsing
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
20
Research direction
Review the existing PYO3 CONFIG mechanism (likely in pyo3 build config crate) and the suggested `pyo3 config var!` macro approach. Examine the comment thread for alternative proposals like a const module. Investigate how values like lib path are extracted and consider exposing them through a public API. Look at the linked issue #2000 for context.