run pip install nvflare==2.1.2 brings wrong protobuf version

[yiheng-wang-nv]

When using pip install nvflare==2.1.2, protobuf 4.21.4 is installed:

Collecting protobuf<5.0.0dev,>=3.15.0
  Downloading protobuf-4.21.4-cp37-abi3-manylinux2014_x86_64.whl (408 kB)

and when starting the server (./poc/server/startup/start.sh), I got the following error:

TypeError: Descriptors cannot not 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If this call came from a _pb2.py file, your generated code is out of date and must be regenerated with protoc 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).

downgrade into 3.20.1 solves the issue:

 pip install protobuf==3.20.1

In the requirements-min.txt of v2.1.2, it specifies to use protobuf==3.20.1 (https://github.com/NVIDIA/NVFlare/blob/2.1.2/requirements-min.txt#L7), but why this requirement does not work when running the pip install command? Is there anything wrong here?

[yiheng-wang-nv]

Update: it seems we can do sth like in: ultralytics/yolov5#8012
set protobuf<=3.20.1

[YuanTingHsieh]

Hi @yiheng-wang-nv thanks for the report!

According to @IsaacYangSLA, the pip install is going to use "setup.py".
Which in our 2.1.2 tag we did not specify the version inside it: https://github.com/NVIDIA/NVFlare/blob/2.1.2/setup.py

I will fix this in the dev branch.

[YuanTingHsieh]

@yiheng-wang-nv , @IsaacYangSLA has created a new tag NVFlare 2.1.3.
It is available: https://pypi.org/project/nvflare/