#!/bin/bash

# wait_for takes a list of container names and runs until all of those container names
# appear in the "/tmp/completed" directory. It can be used to prevent a
# container from executing until pre-requisite containers have indicated completion.

mkdir -p "/tmp/completed"
while true; do
  # Assume we're finished, prove otherwise
  finished=true
  for container in "$@"; do
    if [[ ! -e "/tmp/completed/$container" ]]; then
      printf "Waiting on '%s'...\n" "$container"
      finished=false
      sleep 10
      break
    fi
  done
  if $finished; then
    break
  fi
done