gistfile1.txt

Change this:

function payswarm_hash($obj) {
  // SHA-1 hash JSON
  $options = array('format' => 'application/nquads');
  return 'urn:sha256:' . hash('sha256', jsonld_normalize($obj, $options));
}

To this:

function payswarm_hash($obj) {
  // SHA-1 hash JSON
  $options = array('format' => 'application/nquads');
  $normalized = jsonld_normalize($obj, $options);
  $fp = fopen('/tmp/somefiletologto.txt', 'a');
  fwrite($fp, "\nNORMALIZED:\n$normalized\n");
  fclose($fp);  
  return 'urn:sha256:' . hash('sha256', $normalized);
}