Pass value to cockpit.spawn that can be retrieved in done()/fail() ?

[Mark Reynolds]

Hello,

So I need to loop over a bunch of cockpit.spawns, but after each one is 
done I need to print a success message

for (var attr in mods){
       var cmd = [DSCONF, '-j', 'ldapi://%2fvar%2frun%2f' + server_id + 
'.socket','config', 'replace'];
       cmd.push(attr + "=" + mods[attr]);

cockpit.spawn(cmd, { superuser: true, "err": 
"message"}).done(function() {
         // Success update config_value dict
         config_values[attr] = mods[attr];
         console.log("Success for: " + attr);   // But attr is now 
different!!!!!!
       }).fail(function(data) {
         // Log error and reset the html
         popup_err("Error", "Failed to update attribute: " + attr + 
"\n\n" +  data);
         $("#" + attr).val(config_values[attr]);
       });
     }

The problem is that when the first promise finishes "attr" has already 
changed.  Is there a way to pass/store a copy of "attr" to the spawn() 
command so that it can be accessed in done() & fail()?  I'm not seeing 
anything in the docs to do this, but figured I'd ask.

Thanks,

Mark