How to extend monolog levels in monolog 3

[lerminou]

Monolog version 3

Hi, We were using Monolog 2 and after upgrading to monolog 3, our app is not working anymore.

In monolog2 we have this piece of code in a custom Logger child class to extend monolog levels to add an 'AUDIT' level , for tracability, we need to keep these logs for a long time.

class Logger extends MonologLogger implements LoggerInterface
{
    public static function addLegalLevel()
    {
        self::$levels[LoggerInterface::AUDIT] = 'AUDIT';
    }
}

Now in monolog 3, levels are defined with an ENUM, which cannot be extended. And the \Monolog\Logger class is referencing this ENUM.

What's the new way to extend monolog levels ?

(we Use Symfony too.)

[stof]

Levels are not something that is extendable (that was not really a supported usage of Monolog 2 btw, more a hack of the implementation, and it would not pass static analysis checks).

To me, this is something you should solve with a dedicated channel of MonologBundle (i.e. a dedicated Logger instance with a specific config) rather than a special level.

[lerminou]

Oh, that's a bad news, thanks for the quick response.

Monolog a quite a standard and used is all php libraries. What's the motivation to remove the possiblity to extend it (I just saw a commit to mark Logger as final)

In Symfony, the DI can help us to use the new Logger service, but duplicate the Logger logic is not very interesting

[Seldaek]

IMO custom levels was always a bad idea, because many handlers are built to handle the specific levels monolog ships with. And many log storage backends are also only using the standard 8 levels.

So yes as @stof mentioned using a custom channel so you can store these logs in a special place probably makes most sense. Or tag the logs somehow using a special context/extra data that lets you identify them.