Description

vstinner

opened on Jan 16, 2025

Issue body actions

Feature or enhancement

Proposal:

Python has an internal _PyImport_GetModuleAttrString(mod_name, attr_name) helper function to import a module and get a module attribute. I propose to make this function public to be able to use it outside Python.

UPDATE: Function renamed to PyImport_ImportModuleAttrString().

The function is convenient to use and is used by the following files in Python:

• Modules/arraymodule.c
• Modules/cjkcodecs/cjkcodecs.h
• Modules/_ctypes/callbacks.c
• Modules/_datetimemodule.c
• Modules/_decimal/_decimal.c
• Modules/_elementtree.c
• Modules/faulthandler.c
• Modules/_lsprof.c
• Modules/_operator.c
• Modules/_pickle.c
• Modules/posixmodule.c
• Modules/selectmodule.c
• Modules/_sqlite/connection.c
• Modules/_sqlite/module.c
• Modules/_sre/sre.c
• Modules/timemodule.c
• Modules/_zoneinfo.c
• Objects/abstract.c
• Objects/fileobject.c
• Objects/memoryobject.c
• Parser/pegen.c
• Parser/tokenizer/file_tokenizer.c
• Python/import.c
• Python/pylifecycle.c

Has this already been discussed elsewhere?

No response given

Links to previous discussion of this feature:

No response

Linked PRs

• gh-128911: Add PyImport_ImportModuleAttr() function #128912
• gh-128911: Add tests on the PyImport C API #128915
• [3.13] gh-128911: Add tests on the PyImport C API (#128915) #128960
• [3.12] gh-128911: Add tests on the PyImport C API (GH-128915) (GH-128960) #128989
• gh-128911: Use PyImport_ImportModuleAttr() function #129657

Activity

1. vstinner

   added

   topic-C-API

   type-featureA feature request or enhancementA feature request or enhancement

   on Jan 16, 2025
2. vstinner

   added a commit that references this issue on Jan 16, 2025

   pythongh-128911: Add PyImport_GetModuleAttrString() function

   5f320d1
3. encukou commented on Jan 16, 2025

   

   encukou

   on Jan 16, 2025

   Member

   More actions

   IMO, the *String functions should generally have variants that take PyObject*.
   So, if we add this we should also add PyImport_GetModuleAttr.

   Reacted by Erlend E. Aasland and Bénédikt Tran
4. vstinner

   added 2 commits that reference this issue on Jan 16, 2025

   pythongh-128911: Add tests on the PyImport C API

   1d8342b

   pythongh-128911: Add tests on the PyImport C API

   214b751
5. vstinner commented on Jan 16, 2025

   

   vstinner

   on Jan 16, 2025

   MemberAuthor

   More actions

   So, if we add this we should also add PyImport_GetModuleAttr.

   Ok, I added PyImport_GetModuleAttr() to my PR.
6. vstinner

   added 4 commits that reference this issue on Jan 17, 2025

   gh-128911: Add tests on the PyImport C API (#128915)

   d95ba9f

   pythongh-128911: Add tests on the PyImport C API (python#128915)

   a53147b

   pythongh-128911: Add tests on the PyImport C API (python#128915)

   4f21755

   [3.13] gh-128911: Add tests on the PyImport C API (#128915) (#128960)

   34ded1a
7. serhiy-storchaka

   added a commit that references this issue on Jan 18, 2025

   [3.12] [3.13] pythongh-128911: Add tests on the PyImport C API (pytho…

   96e0bc4
8. vstinner

   added a commit that references this issue on Jan 19, 2025

   [3.12] gh-128911: Add tests on the PyImport C API (GH-128915) (GH-128960

   83de72e
9. malemburg commented on Jan 20, 2025

   

   malemburg

   on Jan 20, 2025

   Member

   More actions

   This sounds like a useful addition. The fact that the internal API is already used a lot in CPython is evidence enough 😄

   And BTW: I like that you're starting to approach C API design from the perspective of a C programmer again.

   Rich C APIs make it a joy programming against them, while minimalist APIs only result in others creating additional layers on top, which adds fragmentation, overall increased maintenance and loss of design control. 👍
10. srinivasreddy

    added a commit that references this issue on Jan 21, 2025

    pythongh-128911: Add tests on the PyImport C API (python#128915)

    d42d098
11. vstinner

    changed the title [-][C API] Add PyImport_GetModuleAttrString(mod_name, attr_name) helper function[/-] [+][C API] Add PyImport_ImportModuleAttr(mod_name, attr_name) helper function[/+] on Jan 26, 2025
12. vstinner commented on Jan 27, 2025

    

    vstinner

    on Jan 27, 2025

    MemberAuthor

    More actions

    See also #129367 which proposes adding PySys_GetAttr().
13. vstinner

    added a commit that references this issue on Jan 30, 2025

    gh-128911: Add PyImport_ImportModuleAttr() function (#128912)

    3bebe46
14. vstinner

    closed this as completedon Jan 30, 2025
15. vstinner

    added 2 commits that reference this issue on Feb 4, 2025

    pythongh-128911: Use PyImport_ImportModuleAttr() function

    76ba47e

    gh-128911: Use PyImport_ImportModuleAttr() function (#129657)

    dc804ff
16. srinivasreddy

    added 2 commits that reference this issue on Feb 7, 2025

    pythongh-128911: Add PyImport_ImportModuleAttr() function (python#128912

    2721adc

    pythongh-128911: Use PyImport_ImportModuleAttr() function (python#129657

    92260e3
17. cmaloney

    added a commit that references this issue on Feb 8, 2025

    pythongh-128911: Use PyImport_ImportModuleAttr() function (python#129657

    8ed58cd

Issue actions