Generic TCP ambassador.
Full credit to SvenDoweit. I'd fork it but I can't do that with a subfolder: https://github.com/SvenDowideit/dockerfiles/tree/master/ambassador
Details of the ambassador pattern here: https://docs.docker.com/engine/articles/ambassador_pattern_linking/
The TLDR is that you use this to avoid hard-coding networking details in the primary container. A secondary bonus is that DNS lookup appears to happen each new connection using the system's resolver, making it perfect for ELB.
Include in the
docker-compose.yml of the relevant projects whenever
ambassadorial services are required.