In Google app Engine py2.7 standard I mainly use cloud endpoint framework to make web apis,
They use protorpc their to make serialization and deserialize and parhaps more.

But in GAE py3, they don't support cloud endpoint framework, so our team want to migrate to flask but want strict serialization in json like protorpc, ( structured json )
There is many alternatives, grpc is one of them and also support http2 stream, protobuff

So I'm confuse how protorpc different from grpc
Are protorpc use same architecture and protobuffer internally ?