#!/bin/sh

command -v docker > /dev/null 2>&1 || {
  echo "Unable to find \`docker' on your \$PATH, is it installed?" >&2
  exit 1
}

docker version | grep -q "Server version\|Server:" || {
  echo "Unable to run \`docker version', the docker daemon may not be running" >&2

  if [ "$(id --user)" -eq 0 ]; then
    echo "Please ensure \`sudo docker version' succeeds and try again" >&2
  else
    echo "Please ensure \`docker version' succeeds and try again" >&2
  fi

  exit 1
}