A tiny binary for testing port forwarding. The following environment variables
control the binary's logic:
BIND_PORT - the TCP port to use for the listener
EXPECTED_CLIENT_DATA - data that we expect to receive from the client; may be "".
CHUNKS - how many chunks of data we should send to the client
CHUNK_SIZE - how large each chunk should be
CHUNK_INTERVAL - the delay in between sending each chunk
Log messages are written to stdout at various stages of the binary's execution.
Test code can retrieve this container's log and validate that the expected
behavior is taking place.