Downlaod, build and install openssl into /usr/local/occlum/x86_64-linux-musl/lib:

./download_and_install_openssl.sh

Download, build and install cares, protobuf and finally gRPC into /usr/local/occlum/x86_64-linux-musl/lib:

./download_and_install_grpc.sh

Prepare the gRPC C++ Hello World sample project, which consists of a client and server:

./prepare_client_server.sh

Then you can see the source code in client and server if you want.

Run the demo server which will listen on port 50051 on occlum:

./run_server_on_occlum.sh

or on host:

./run_server_on_host.sh

Then you can invoke gRPC service by running client in a different terminal on occlum:

./run_client_on_occlum.sh

or on host:

./run_server_on_host.sh

And you will see the "Greeter received: Hello world" in the client side output.