wait-for-container-to-exit.sh script is not swarm friendly

[johnmanko]

With swarms, the container name is dynamic. More so, container_name in the compose file won't work with them. Perhaps a better way to search for a running instance of the WAITFORIT_CONTAINER is to look for an image ancestor. Below is an example where is looks for zero running containers. (I also locked the API version to v1.4 in case future versions of Docker change the default API):

wait_for()
{
  while :
  do

    INSPECT_CONTAINER=`curl --silent --unix-socket /var/run/docker.sock ${API_SERVER}/v1.40/containers/json?filters=%7B%22ancestor%22%3A%5B%22${WAITFORIT_CONTAINER}%22%5D%7D`

    INSPECT_CONTAINER_RESULT=$(jq --raw-output '. | length' <<< "${INSPECT_CONTAINER}")

    # echoerr $INSPECT_CONTAINER_RESULT

    if [[ $INSPECT_CONTAINER_RESULT == "0" ]]; then
      exec "${WAITFORIT_CLI[@]}"
      exit
    else
      sleep $WAITFORIT_TIMEOUT
    fi

  done
}

And it's usage would be something like:

    command: ["/wait-for-container-to-exit.sh", "jasperserver-ce-cmdline:7.8.0", "-t" , "30", "--", "/entrypoint-ce.sh", "run"]