title: Running a docker-based lambda with SAM and docker-compose
body: <p>Trying to build a docker based lambda using SAM and test it locally within a docker-compose, as the lambda needs to server other components built by the compose.
  Thing is, SAM itself runs in a container which means that I'm not clear on how to build that container within the docker-compose file and have it run the <code>sam build</code> and <code>sam local start-api</code></p>
  <p>Any general guidelines on how to build the <code>docker-compose.yml</code> file and any other must have resources would be helpful!</p>