v3.4.0

Features

• (experimental) RPC handlers passed to register_x functions may now have a member function called request_message_factory() whose return object will be used to create the initial request message in unary and server-streaming rpcs. This can be used to allocate the message in a protobuf arena (example) or reuse it between rpcs.
• Make Asio based register_x functions compatible with GrpcContext::run_completion_queue/poll_completion_queue()
• Cleanup asio-grpc.natvis and add support for Asio+libunifex/stdexec mixed builds.

Performance

• Changed GrpcContext::shutdown_ from atomic to regular bool. This bool is checked at the start and end of every asynchronous operation.

Documentation

• Add server example showing how to use an asio::io_context as the main execution context and a GrpcContext on a separate thread with GrpcContext::run_completion_queue().