[Question] How to use protoc instead of buf in a python project

[jmspereira]

Hey everyone, sorry if this issue is duplicated, but I didn't find any that addressed the entire process or I am missing something when using protoc instead of buf. I have a python project with a set of protobuf files, I am compiling them with:

protoc <protobuf-files> 
-I/usr/local/include/protovalidate  
--fatal_warnings 
--python_out=/<outpath> 
--pyi_out=/<outpath>  
--include_imports 
--descriptor_set_out=<outpath>/gen

Where the include_imports and the descriptor_set_out were set as documented. However, even when I define the PYTHONPATH to the gen file, still does not work, with the following error:

>>> import protovalidate
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/venv/lib/python3.11/site-packages/protovalidate/__init__.py", line 15, in <module>
    from protovalidate import validator
  File "/venv/lib/python3.11/site-packages/protovalidate/validator.py", line 19, in <module>
    from buf.validate import expression_pb2  # type: ignore
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
ModuleNotFoundError: No module named 'buf'

This is likely because this is not generating the validate_pb2.py but a binary file. So, what is the correct process in order to use protovalidate with protoc in a python project?

Thanks!

[jmspereira]

Discussed in bufbuild/protovalidate-python#237