This is NOT a best practice and is ONLY for an emergency situation. However, it is good
to use the LoggerInterface
throughout your code and add generous parameters to the array.
// Generate an exception so we can get the stack trace.
// We could use debug_backtrace, but it's easy to arguments and thus take the site down.
$ex = new Exception();
// Log it out. Don't forget the critically-helpful parameters array. Put anything
// and everything here.