pip install etcd3 does not work because of an incompatible protobuf version

[arturo-air]

I spent a few hours trying multiple python etcd3 clients, and all failed because of protobuf. The steps were:

1. Run pip install etcd3.
2. Open the python interpreter.
3. Type import etcd3.
4. Got an error related to protobuf.

Python 3.12.3 (main, Nov  6 2024, 18:32:19) [GCC 13.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import etcd3
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/tmp/venv/lib/python3.12/site-packages/etcd3/__init__.py", line 3, in <module>
    import etcd3.etcdrpc as etcdrpc
  File "/tmp/venv/lib/python3.12/site-packages/etcd3/etcdrpc/__init__.py", line 1, in <module>
    from .rpc_pb2 import *
  File "/tmp/venv/lib/python3.12/site-packages/etcd3/etcdrpc/rpc_pb2.py", line 16, in <module>
    from etcd3.etcdrpc import kv_pb2 as kv__pb2
  File "/tmp/venv/lib/python3.12/site-packages/etcd3/etcdrpc/kv_pb2.py", line 33, in <module>
    _descriptor.EnumValueDescriptor(
  File "/tmp/venv/lib/python3.12/site-packages/google/protobuf/descriptor.py", line 920, in __new__
    _message.Message._CheckCalledFromGeneratedFile()
TypeError: Descriptors cannot be created directly.
If this call came from a _pb2.py file, your generated code is out of date and must be regenerated with protoc >= 3.19.0.
If you cannot immediately regenerate your protos, some other possible workarounds are:
 1. Downgrade the protobuf package to 3.20.x or lower.
 2. Set PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION=python (but this will use pure-Python parsing and will be much slower).

More information: https://developers.google.com/protocol-buffers/docs/news/2022-05-06#python-updates

The solution is, either modify the requirements.txt to force using protobuf v3, or install the library directly from the sources:

pip install git+https://github.com/kragniz/python-etcd3.git@e58a899579ba416449c4e225b61f039457c8072a

Please, I suggest pushing the latest GitHub version to Pypi. If not, other people is going to get the same error.