Psr Log Aware Trait Laravel Package

Getting Started

This package provides a simple trait (Mpdf\PsrLogAwareTrait) to make classes compatible with any PSR-3 logger implementation — regardless of whether your project uses psr/log v1, v2, or v3. Start by including it in any class that needs to accept and use a PSR-3 logger:

use Mpdf\PsrLogAwareTrait;
use Psr\Log\LoggerInterface;

class MyService
{
    use PsrLogAwareTrait;

    public function __construct(?LoggerInterface $logger = null)
    {
        $this->setLogger($logger);
    }

    public function doSomething()
    {
        $this->logger->info('Starting process…');
        // ...
    }
}

No further setup is required — the trait handles internal logger compatibility behind the scenes.

Implementation Patterns

• Lazy Logger Setup: Use the trait in long-lived services or libraries that may be instantiated before a logger is available. Call setLogger() early in the request lifecycle.
• Library Compatibility: Ideal for reusable packages (e.g., middleware, formatters, workers) that need to support multiple PSR-3 versions without enforcing version constraints that conflict with app dependencies.
• Null-Safe Integration: Works seamlessly with null loggers — no extra if ($this->logger) checks needed.
• Type Hinting: Always type-hint Psr\Log\LoggerInterface (or ?LoggerInterface for optional), not concrete implementations.

Gotchas and Tips

• ❗ Not a Logger Itself: This trait adds logger support to your class — it does not provide logging functionality. You still need to inject a valid PSR-3 logger.
• ❗ Trait Name: Despite the namespace (Mpdf\…), it’s not tied to the mpdf/mpdf package — it’s generic and version-agnostic.
• ⚠️ No Autoloading Requirement: The trait is light (~15 lines) but verify it’s installed via Composer (via transitive dependency, likely via mpdf/mpdf). Run composer show mPDF/psr-log-aware-trait to confirm.
• 🔍 Debugging Tips: If your logger calls silently fail, check:
  • You called setLogger() — the trait doesn’t auto-inject.
  • Your app’s psr/log version doesn’t conflict with how other packages expect it (e.g., mpdf/mpdf historically lagged on PSR-3 v2+ support — this trait helps bridge that).
• 🧩 Extension: You can use this alongside other traits (e.g., configuration, caching) — no naming conflicts expected.
• 📦 Why Still Used?: Though modern Symfony/Laravel apps often auto-configure loggers, this remains useful for:
  • Legacy codebases
  • Composer plugin systems
  • Packages that must avoid psr/log version conflicts (e.g., ^1.0 || ^2.0 || ^3.0)