#!/bin/bash

# wait_for takes a container name and runs until the named container has
# reported a "SUCCESS" or "FAILURE" status in the "/tmp/status" directory.
# When the status becomes "SUCCESS" or "FAILURE", the `wait_for` script exits
# with a corresponding exit code. It can be used to prevent a container from
# executing until pre-requisite containers have indicated successful
# completion.

container="$1"
mkdir -p "/tmp/status"
status_file="/tmp/status/$container"
if [[ ! -e "$status_file" ]]; then
  # Create the status file to prevent errors when checking its contents
  touch "$status_file"
fi

while true; do
  # Assume we're finished, prove otherwise
  finished=true
  for container in "$@"; do
    if (! grep -q -e "SUCCESS" -e "FAILURE" "$status_file"); then
      printf "Waiting on status from '%s'...\n" "$container"
      finished=false
      sleep 10
      break
    fi
  done
  if $finished; then
    break
  fi
done

if (grep -q "SUCCESS" "$status_file"); then
  exit 0
else
  exit 1
fi