[Request] Docker-friendly logging

[bkuhl]

Docker expects all logs to be sent to stdout and stderr and Laravel doesn't seem to have the ability to separate logs in such a way, but requires all logs go to either rather than the ability to split them up. It'd be great if we were able to send error logs to stderr and the rest of the logs to stdout.

[guiwoda]

You can, but not directly through Laravel's Log facade. You need to add two handlers to Monolog:

$monolog = Log::getMonolog();

// Always add the stderr output for errors over WARNING level.
$monolog->pushHandler(
    new \Monolog\Handler\StreamHandler('php://stderr', \Monolog\Logger::WARNING)
);

// Conditionally add stdout debug.
if (config('app.debug')) {
    $monolog->pushHandler(
        new \Monolog\Handler\StreamHandler('php://stdout', \Monolog\Logger::DEBUG)
    );
}

Something along those lines!

EDIT: I understand that the stdout Handler will also get errors. I'm looking up ways to configure a max level in Monolog, but this would be a minor problem, as stdout should only be done in a debug setup.

[bbjay]

didn't know where to put the sample above...
combining the code above with the advice given in this answer worked for me:
http://stackoverflow.com/questions/32552450/laravel-how-to-log-info-to-separate-file

In bootstrap/app.php:

$app->configureMonologUsing(function($monolog) {
    // Always add the stderr output for errors over WARNING level.
    $monolog->pushHandler(
        new \Monolog\Handler\StreamHandler('php://stderr', \Monolog\Logger::WARNING)
    );
});

[andersonn-roberto]

Tank you a lot @bbjay and @guiwoda !
I was spending a lot of time trying to figure out what was wrong with my app, the error only said that Laravel can't create a singleLog.
After inserting your code on bootstrap/app.php the truly error showed up.

Thanks!

[gnumoksha]

For Lumen 5.4.*:

bootstrap/app.php

[...]

$app->configureMonologUsing(function ($monolog) {
    $monolog->pushHandler(new \Monolog\Handler\StreamHandler('php://stderr', \Monolog\Logger::WARNING));

    return $monolog;
});

return $app;

[Yo1L]

A solution with no code, only configuration for Laravel and Apache.
I’ve just set up Monolog to log in errorlog and Apache redirects ErrorLog in stdout.

.env

APP_LOG=errorlog

apache2 site conf

  ErrorLog /dev/stderr
  TransferLog /dev/stdout

I think you could do the same with nginx.

[lifeofguenter]

thanks @YoannLeViavant - this also works very well with docker/php-fpm

[taylorotwell]

New logging should be able to handle this.

[taylorotwell]

I've added an example to the default logging configuration file of how to do this.

[nasikshafeek]

@taylorotwell Is there any handlers for us to route logs to STDOUT? (I can see StreamHandler is for STDERR messages)

[mfn]

@kisanme The streamhandler is for streams, it does not matter where to.

You can use 'driver' => 'custom' and use 'via' => SetupYourLogger::class to set it up in any way, e.g. create a StreamHandler for stdout, etc.

Also see https://laravel.com/docs/5.6/logging#creating-channels-via-factories .

[nasikshafeek]

Figured that out @mfn
I've edited what @taylorotwell 's configuration looks like for STDERR to STDOUT. It looks like the following, without need of creating a factory class:

       # In config/logging.php

       'stdout' => [
           'driver'  => 'monolog',
           'handler' => StreamHandler::class,
           'with'    => [
               'stream' => 'php://stdout',
           ],
       ],

[SecondeJK]

Surely this should be included out the box?

[whereisaaron]

In recent versions (5.6+) the default config/logging.php appears to include a stderr config, so you can just inject a LOG_CHANNEL=stderr environment variable into the container.

        'stderr' => [
            'driver' => 'monolog',
            'handler' => StreamHandler::class,
            'with' => [
                'stream' => 'php://stderr',
            ],
        ],