<?php
exec("docker images -aq", $res, $ret);
if ($ret!=0) {
  echo 'digraph {';
  echo '  A [label="Error\nCannot get Docker Images"];';
  echo '  B [label="Does the Webserver have Docker rights?"];';
  echo '  A->B [label="Probable\nCause"];';
  echo '}';
  return;
}
exec("docker inspect ".join(" ", $res), $res2, $ret);
if ($ret==0) {
  $images=json_decode(join($res2), true);
  echo "digraph {\n";
  echo "  rankdir=TB;\n";

  foreach ($images as $i) {
    $name = "";
    if (isset($i['RepoTags']) && count($i['RepoTags'])>0) {
      $name = join("\\n", $i['RepoTags']);
      if (isset($i['Author']) && $i['Author']!="") $name .= '\\n['.$i['Author'].']';
    }
    echo '  "'.$i['Id'].'" [label="'.$name.'"];'."\n";
  }

  foreach ($images as $i) {
    if (isset($i['Parent']) && $i['Parent']!="")
      echo '  "'.$i['Parent'].'" -> "'.$i['Id'].'";'."\n";
  }
  
  echo "}";
} else {
  echo 'digraph {';
  echo '  A [label="Error\nCannot Inspect Docker Container"];';
  echo '}';
  return;
}

?>