Hello, I’m a bit confused about Protobuf package declarations and how they’re compiled to a Python package.
>From the Python docs <https://protobuf.dev/reference/python/python-generated/#package>: *The Python code generated by the protocol buffer compiler is completely unaffected by the package name defined in the .proto file. Instead, Python packages are identified by directory structure.* Take Google’s *Timestamp <https://github.com/protocolbuffers/protobuf/blob/9b4a3ed9e46b2542185ce6f6e21656955708808f/src/google/protobuf/timestamp.proto#L33>* for example: the declared package is *package google.protobuf* When I install the googleapis-common-protos <https://github.com/googleapis/python-api-common-protos/tree/main/google> Python package, then the *Timestamp* class lives in google/protobuf/timestamp_pb2.py — so that’s the *google.protobuf* package <https://docs.python.org/3/tutorial/modules.html#packages>, and the *timestamp_pb2* module <https://docs.python.org/3/tutorial/modules.html> according to Python. Looking at the information built into the compiled Python class, I see only the original Protobuf package information: *>>> from google.protobuf.timestamp_pb2 import Timestamp>>> >>> Timestamp.DESCRIPTOR.file.name'google/protobuf/timestamp.proto'>>> Timestamp.DESCRIPTOR.file.package'google.protobuf'>>> Timestamp.DESCRIPTOR.full_name'google.protobuf.Timestamp'* Note that *google.protobuf.Timestamp* is actually *not* a valid Python package/module, and therefore it’s not possible (by default) to import classes based on their declared package names: *>>> importlib.import_module(Timestamp.DESCRIPTOR.full_name)ModuleNotFoundError: No module named 'google.protobuf.Timestamp'* or the incorrect package is being imported: *>>> importlib.import_module(Timestamp.DESCRIPTOR.file.package)<module 'google.protobuf' from '/path/to/.venv/lib/python3.10/site-packages/google/protobuf/__init__.py'>* which doesn’t actually contain the *Timestamp* class. That, in turn, makes it difficult to recursively walk and load nested Protobuf messages in Python! So… what’s the recommendation here for my own Protobuf packages? Should I name them such that they match the Python package names (and thereby confuse other languages) or should I stick with Google’s example and skip the file name in the package declaration (i.e. the Python module)? Does it matter? How do I programmatically walk the compiled Python classes for nested Protobuf messages? Much thanks! Jens -- You received this message because you are subscribed to the Google Groups "grpc.io" group. To unsubscribe from this group and stop receiving emails from it, send an email to grpc-io+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/grpc-io/4e122401-f3d4-417f-8e25-d5b2e0b4212fn%40googlegroups.com.
