HowTo Update PodResources gRPC API¶

Preparing the new api.proto¶

Copy the api.proto from K8s sources to kuryr_kubernetes/pod_resources/ and remove all the lines that contains gogoproto since this is unwanted dependency that is not needed for python bindings:

$ sed '/gogoproto/d' \
  ../kubernetes/pkg/kubelet/apis/podresources/<version>/api.proto \
  > kuryr_kubernetes/pod_resources/api.proto

Don’t forget to update the file header that should point to the original api.proto and to this reference document:

// Generated from kubernetes/pkg/kubelet/apis/podresources/<version>/api.proto
// To regenerate api.proto, api_pb2.py and api_pb2_grpc.py follow instructions
// from doc/source/devref/updating_pod_resources_api.rst.

Generating the python bindings¶

• (Optional) Create the python virtual environment:

[kuryr-kubernetes]$ python3 -m venv venv
[kuryr-kubernetes]$ . ./venv/bin/activate

• To generate python bindings we need a protoc compiler and the gRPC plugin for it. The most simple way to get them is to install grpcio-tools:

  (venv) [kuryr-kubernetes]$ pip install grpcio-tools==1.19
  

  Note

  We’re installing specific version of grpcio-tools to get specific version of protoc compiler. The version of protoc compiler should be equal to the protobuf package version in lower-constraints.txt. This is because older protobuf might be not able to use files generated by newer compiler. In case you need to use more recent compiler, you need update requirements.txt and lower-constraints.txt accordingly.

  To check version of compiler installed with grpcio-tools use:

  (venv) [kuryr-kubernetes]$ python -m grpc_tools.protoc --version
  libprotoc 3.6.1
  

• Following command will generate api_pb2_grpc.py and api_pb2.py:

  (venv) [kuryr-kubernetes]$ python -m grpc_tools.protoc -I./               \
      --python_out=. --grpc_python_out=.      \
      kuryr_kubernetes/pod_resources/api.proto