A service to provide gRPC server information [information service]

[whynowy]

Summary

With Python SDK supporting asyncio + multi multiprocessing (which requires to use TCP gRPC connection instead of UDS), the numa container needs to know what is the right protocol it should use to start the connection. The proposal here is to start a service in the UDF/UDSink at the time it starts the gRPC server, and the client (numa container) will access this service to get the protocol information to start the right gRPC connection.

This information service will be only useful at the time the pod starts, according to this, one option is to use FIFO for the implementation.

The returned information could include more than the protocol, for example:

• language
• sdk version
• protocal
• some other metadata

This could also be used for the client to determine what is the right version to communicate for backward compatibility purposes.

• Golang (server + client)
• Python (server)
• Server info writer in Java SDK #682