Disabling node editing after first node flagging I use flagging for signing petitions. Petitions should be editable until the first signing (flagging) is done.

Now I look for a solution to disable node edition after first signing.

My first thought is doing it with Rules. I have access to flagging reactions, node type conditions but I have no action for editability of nodes.

Is there another way to get it done with Rules or something without it?
D7, no need of rules, place this code in your MODULE

function MODULE_node_access($node, $op, $account) {
 if ($op == 'update') {
  $flag='';
  $flag = flag_get_flag('YOUR_FLAG_MACHINE_NAME');
            if ($flag &amp;&amp; $flag-&gt;is_flagged($node-&gt;nid, $GLOBALS['user']-&gt;uid)) {
  return NODE_ACCESS_DENY;
    }
  }
}


done, enyoy.