This repository holds all interfaces/classes/traits related to

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:


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 {
        } 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.