Formatter.php

<?php

declare (strict_types=1);
namespace OpenTelemetry\API\Behavior\Internal\LogWriter;

class Formatter {
    public static function format($level, string $message, array $context) : string {
        $exception = array_key_exists('exception', $context) && $context['exception'] instanceof \Throwable ? $context['exception'] : null;
        if ($exception) {
            $previous = $exception->getPrevious() ? $exception->getPrevious()
                ->getMessage() : '';
            $message = sprintf('OpenTelemetry: [%s] %s [exception] %s [previous] %s%s%s', $level, $message, $exception->getMessage(), $previous, PHP_EOL, $exception->getTraceAsString());
        }
        else {
            
            //get calling location, skipping over trait, formatter etc
            $caller = debug_backtrace()[3];
            
            /**
             * @psalm-suppress PossiblyNullArgument
             * @psalm-suppress PossiblyUndefinedArrayOffset
             */
            $message = sprintf('OpenTelemetry: [%s] %s in %s(%s)', $level, $message, $caller['file'], $caller['line']);
        }
        return $message;
    }

}