make severity an enum only

examples/logs/logger_builder.php

@@ -3,6 +3,7 @@
 declare(strict_types=1);
 
 use OpenTelemetry\API\Logs\LogRecord;
+use OpenTelemetry\API\Logs\Severity;
 use OpenTelemetry\SDK\Common\Attribute\Attributes;
 use OpenTelemetry\SDK\Logs\Exporter\ConsoleExporterFactory;
 use OpenTelemetry\SDK\Logs\LoggerProvider;
@@ -24,7 +25,7 @@ $logger = $loggerProvider->getLogger('demo', '1.0', 'http://schema.url', ['foo'
 
 $record = (new LogRecord(['foo' => 'bar', 'baz' => 'bat', 'msg' => 'hello world']))
     ->setSeverityText('INFO')
-    ->setSeverityNumber(9);
+    ->setSeverityNumber(Severity::INFO);
 
 /**
  * Note that Loggers should only be used directly by a log appender.

src/API/Logs/EventLoggerInterface.php

@@ -16,7 +16,7 @@ interface EventLoggerInterface
         mixed $payload = null,
         ?int $timestamp = null,
         ?ContextInterface $context = null,
-        Severity|int|null $severityNumber = null,
+        ?Severity $severityNumber = null,
         ?array $attributes = [],
     ): void;
 }

src/API/Logs/LogRecord.php

@@ -42,9 +42,9 @@ class LogRecord
     /**
      * @see https://opentelemetry.io/docs/reference/specification/logs/data-model/#field-severitynumber
      */
-    public function setSeverityNumber(Severity|int $severityNumber): self
+    public function setSeverityNumber(Severity $severityNumber): self
     {
-        $this->severityNumber = ($severityNumber instanceof Severity) ? $severityNumber->value : $severityNumber;
+        $this->severityNumber = $severityNumber->value;
 
         return $this;
     }

src/API/Logs/Map/Psr3.php

@@ -4,28 +4,30 @@ declare(strict_types=1);
 
 namespace OpenTelemetry\API\Logs\Map;
 
+use InvalidArgumentException;
+use OpenTelemetry\API\Logs\Severity;
 use Psr\Log\LogLevel;
 
 class Psr3
 {
     /**
-     * Maps PSR-3 severity level (string) to the appropriate opentelemetry severity number
+     * Maps PSR-3 severity level (string) to the appropriate opentelemetry severity
      *
      * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/logs/data-model-appendix.md#appendix-b-severitynumber-example-mappings
      * @see https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/logs/data-model.md#field-severitynumber
      */
-    public static function severityNumber(string $level): int
+    public static function severityNumber(string $level): Severity
     {
         return match (strtolower($level)) {
-            LogLevel::DEBUG => 5,
-            LogLevel::INFO => 9,
-            LogLevel::NOTICE => 10,
-            LogLevel::WARNING => 13,
-            LogLevel::ERROR => 17,
-            LogLevel::CRITICAL => 18,
-            LogLevel::ALERT => 19,
-            LogLevel::EMERGENCY => 21,
-            default => 0,
+            LogLevel::DEBUG => Severity::DEBUG,
+            LogLevel::INFO => Severity::INFO,
+            LogLevel::NOTICE => Severity::INFO2,
+            LogLevel::WARNING => Severity::WARN,
+            LogLevel::ERROR => Severity::ERROR,
+            LogLevel::CRITICAL => Severity::ERROR2,
+            LogLevel::ALERT => Severity::ERROR3,
+            LogLevel::EMERGENCY => Severity::FATAL,
+            default => throw new InvalidArgumentException('Unknown severity: ' . $level),
         };
     }
 }

src/SDK/Logs/EventLogger.php

@@ -26,7 +26,7 @@ class EventLogger implements EventLoggerInterface
         mixed $payload = null,
         ?int $timestamp = null,
         ?ContextInterface $context = null,
-        Severity|int|null $severityNumber = null,
+        ?Severity $severityNumber = null,
         ?array $attributes = [],
     ): void {
         $logRecord = new LogRecord();
@@ -35,7 +35,7 @@ class EventLogger implements EventLoggerInterface
         $payload && $logRecord->setBody($payload);
         $logRecord->setTimestamp($timestamp ?? (int) (microtime(true)*LogRecord::NANOS_PER_SECOND));
         $context && $logRecord->setContext($context);
-        $logRecord->setSeverityNumber($severityNumber ?? Severity::INFO);
+        $severityNumber && $logRecord->setSeverityNumber($severityNumber);
 
         $this->logger->emit($logRecord);
     }

tests/Unit/API/Logs/LogRecordTest.php

@@ -33,7 +33,6 @@ class LogRecordTest extends TestCase
         return [
             ['setBody', 'body', 'foo'],
             ['setAttributes', 'attributes', ['foo' => 'bar']],
-            ['setSeverityNumber', 'severityNumber', 5],
             ['setSeverityNumber', 'severityNumber', Severity::ERROR, Severity::ERROR->value],
             ['setSeverityText', 'severityText', 'info'],
             ['setObservedTimestamp', 'observedTimestamp', 999],

tests/Unit/API/Logs/Map/Psr3Test.php

@@ -32,7 +32,12 @@ class Psr3Test extends TestCase
             [LogLevel::NOTICE],
             [LogLevel::INFO],
             [LogLevel::DEBUG],
-            ['unknown'],
         ];
     }
+
+    public function test_unknown_value_error(): void
+    {
+        $this->expectException(\InvalidArgumentException::class);
+        Psr3::severityNumber('unknown');
+    }
 }

tests/Unit/SDK/Logs/ReadableLogRecordTest.php

@@ -5,6 +5,7 @@ declare(strict_types=1);
 namespace OpenTelemetry\Tests\Unit\SDK\Logs;
 
 use OpenTelemetry\API\Logs\LogRecord;
+use OpenTelemetry\API\Logs\Severity;
 use OpenTelemetry\Context\ContextInterface;
 use OpenTelemetry\SDK\Common\Attribute\AttributesFactory;
 use OpenTelemetry\SDK\Common\Instrumentation\InstrumentationScopeInterface;
@@ -39,7 +40,7 @@ class ReadableLogRecordTest extends TestCase
     public function test_getters(): void
     {
         $logRecord = (new LogRecord('body'))
-            ->setSeverityNumber(5)
+            ->setSeverityNumber(Severity::DEBUG)
             ->setSeverityText('info')
             ->setTimestamp(11)
             ->setObservedTimestamp(22)