grpc_php_plugin protoc plugin
You need the grpc_php_plugin to generate the PHP client stub classes. This plugin works with the main protoc binary to generate classes that you can import into your project.
Find latest releases here: https://github.com/grpc/grpc/releases
You can build grpc_php_plugin with cmake:
# git clone -b v1.51.3 https://github.com/grpc/grpc
# cd grpc
# git submodule update --init
# mkdir -p cmake/build
# cd cmake/build
# cmake ../..
# make protoc grpc_php_plugin
# cp /root/grpc/cmake/build/grpc_php_plugin /usr/local/bin/
The commands above will make protoc and grpc_php_plugin available in cmake/build/third_party/protobuf/protoc and cmake/build/grpc_php_plugin.