Question

This user asked a similar question but had no viable solution in the answers, so here is am revisiting the topic.

I would like to have emails sent from custom exceptions in a clean way. I can do this easy with plain old errors from a custom error_handler, but with extended exceptions I am a bit stumped.

The main problem is I rely on Zend_Mail to have transparent cross-platform mailing, easy smtp/ssl configuration for gmail account usage and a bunch of other goodies. I would like to access my Zend_Mail object in a custom exception. Static calls are not really an option that I am willing to use, although it seems to be the easiest to use a 3rd party object in a custom exception. Here is the constructer of base exception class:

 public function __construct($message = null, $code = 0,
                             Exception $previous = null);

The only solution I think may be worthwhile at the time being is adding a parameter for mailer object in the extended exception class, yet I do not want to require all subclasses to pass in mailer object. The idea is that maybe this mailer obj. would be better off being an optional dependency.

__construct signature would then become:

      public function __construct($mailobj = null, $message = null, $code = 0,
                                  Exception $previous = null);  

Notice the order of parameters, only $code is required and it is in the middle of the signature! This poses another issue but that is for another day. My question for today is, does anyone have ideas / suggestions on how to deal with dependencies in custom exception classes?
Keep in mind we are aiming for testable code.

Another easy option would have been to have the mailing code in a catch block, but that kind of defeats the purpose of using custom exceptions in my opinion, because the client of this class now has to think of adding mailing code in all catch blocks.

Answer 1

I would approach it like this (am I missing some requirement here?)

class CustomException extends Exception // Zend_Exception?
{
    public function __construct($message = null, $code = 0, Exception $previous = null) {
        $mailobj = new Zend_Mail(/* ... */);
        // ....
        try {  // In order not to get infinitelly looped
            $mailobj->send(/*...*/);
        } catch(Exception $e) { }
    }
}

Whenever this exception is instantiated (i.e. throw new CustomException() ), someone will be receiving an email.