This repository holds all interfaces/classes/traits related to PSR-3.

Note that this is not a logger of its own. It is merely an interface that describes a logger. See the specification for more details.

composer require psr/log

If you need a logger, you can use the interface like this:

<?php
use Psr\Log\LoggerInterface;
class Foo
{
 private $logger;
 public function __construct(LoggerInterface $logger = null)
 {
 $this->logger = $logger;
 }
 public function doSomething()
 {
 if ($this->logger) {
 $this->logger->info('Doing work');
 }
 
 try {
 $this->doSomethingElse();
 } catch (Exception $exception) {
 $this->logger->error('Oh no!', array('exception' => $exception));
 }
 // do something useful
 }
}

You can then pick one of the implementations of the interface to get a logger.

If you want to implement the interface, you can require this package and implement Psr\Log\LoggerInterface in your code. Please read the specification text for details.