README

SuperKernel Logger

super-kernel/logger provides the standard output logger that SuperKernel's packages write to, and a factory for the Monolog loggers an application creates for itself.

Installation

composer require super-kernel/logger

The package uses Monolog and has no requirement beyond PHP. The standard output logger is a container service: it is found in the metadata that skernel build generates, so a project needs SKERNEL to build it.

What it provides

StdoutLoggerInterface, which writes INFO and above to the standard output in a readable console format.
Colors on an interactive terminal, and plain output otherwise.
LoggerFactory, which creates a Monolog logger with one stream handler for a channel, a stream, a level, and an optional formatter.
ConsoleFormatter, the console format, for loggers of your own.
Replacement of the standard output logger by an application #[Provider].

It does not:

bind Psr\Log\LoggerInterface; an application chooses that service;
replace placeholders or show context in the console format;
read environment files, redact data, rotate files, or buffer records;
send records to remote services or write asynchronously.

Quick start

Write to the standard output logger from a service. Save it as src/Billing/InvoiceImporter.php:

<?php

declare(strict_types=1);

namespace Src\Billing;

use SuperKernel\Contract\StdoutLoggerInterface;

final readonly class InvoiceImporter
{
    public function __construct(private StdoutLoggerInterface $logger)
    {
    }

    public function import(string $invoiceNumber): void
    {
        $this->logger->debug("Reading invoice {$invoiceNumber}.");
        $this->logger->info("Invoice {$invoiceNumber} imported.");
    }
}

Use the service from a script. Save it as bin/import.php:

<?php

declare(strict_types=1);

use Src\Billing\InvoiceImporter;
use SuperKernel\Context\ApplicationContext;

require dirname(__DIR__) . '/vendor/autoload.php';

ApplicationContext::getContainer()->get(InvoiceImporter::class)->import('INV-1001');

Build the project and run the script:

skernel build
php bin/import.php

It prints a line such as 2026-11-10T10:56:25.283+00:00 [INFO] Invoice INV-1001 imported.; the DEBUG record is below the threshold.

Public surface

Name	Kind	Purpose
`SuperKernel\Contract\StdoutLoggerInterface`	Interface	Provided by the container; the PSR-3 logger that writes to the standard output.
`SuperKernel\Logger\Factory\LoggerFactory`	Class	`create()` returns a new Monolog logger for a channel, stream, minimum level, and optional formatter.
`SuperKernel\Logger\Formatter\ConsoleFormatter`	Class	Formats a record as `<timestamp> [<LEVEL>] <message>`, with colors when `decorated` is `true`.

Behavior to know

The standard output logger writes to php://stdout, so its records mix with a command's own output. Replace it with one that writes to php://stderr or a file when the standard output must stay machine-readable.
The console format shows the message as given: placeholders such as {id} are not replaced, and context and extra data are not shown.
Colors are used only when the standard output is a terminal, NO_COLOR is not set, and TERM is not dumb.
Replace the logger with a class marked #[Provider(StdoutLoggerInterface::class)]. A second #[FactoryProvider] for the interface makes every lookup fail with Factory provider for SuperKernel\Contract\StdoutLoggerInterface is declared by both <class> and SuperKernel\Logger\Provider\StdoutLoggerProvider.
Run skernel build again after adding or changing a replacement, or start with skernel run, which builds first.
LoggerFactory::create() raises Psr\Log\InvalidArgumentException for an unknown level; a stream that cannot be opened or written fails when the first record is written.

Documentation

The developer documentation describes the console format, creating loggers and binding LoggerInterface, replacing the standard output logger, and keeping machine-readable output clean: SuperKernel Logger.

License

Released under the MIT License. See LICENSE.

super-kernel / logger

Package info

Security

Statistics