creating a decoder to treat the traceId and spandId as jaeger client does (#18)

Author: luizmanhani

src/Support/JaegerDecoder.php

@@ -0,0 +1,35 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * This file is part of Hyperf + OpenCodeCo
+ *
+ * @link     https://opencodeco.dev
+ * @document https://hyperf.wiki
+ * @contact  leo@opencodeco.dev
+ * @license  https://github.com/opencodeco/hyperf-metric/blob/main/LICENSE
+ */
+namespace Hyperf\Tracer\Support;
+
+final class JaegerDecoder
+{
+    /**
+     * caused by https://github.com/jonahgeorge/jaeger-client-php/blob/39e35bc3168da12cf596038cd1332e700b5131e9/src/Jaeger/Mapper/SpanToJaegerMapper.php#L181
+     */
+    public static function traceIdDecoder(string $traceId): string
+    {
+        if (strlen($traceId) == 32 || !is_numeric($traceId)) {
+            return $traceId;
+        }
+
+        return substr($traceId, 0, 16) . substr($traceId, -16, 16);
+    }
+
+    public static function spanIdDecoder(string $spanId): string
+    {
+        if (!is_numeric($spanId) || strlen($spanId) == 16) {
+            return $spanId;
+        }
+        return strtolower(dechex((int)$spanId));
+    }
+}

src/Support/TextCodecOtel.php

@@ -111,15 +111,13 @@ public function extract($carrier)
      */
     private function spanContextToString($traceId, $spanId, $flags)
     {
-        if (strlen($traceId) < 32) {
-            $start = mb_substr($traceId, 0, 3);
-            $end = mb_substr($traceId, -3);
-            $middle = mb_substr($traceId, 3, mb_strlen($traceId) - 6);
-            $traceId = $start . $middle . $middle . $end;
-            $spanId = strtolower(dechex((int)$spanId));
-        }
         $flags = str_pad($flags, 2, "0", STR_PAD_LEFT);
-        return sprintf('%s-%s-%s-%s', self::VERSION, $traceId, $spanId, $flags);
+        return sprintf('%s-%s-%s-%s',
+            self::VERSION,
+            JaegerDecoder::traceIdDecoder($traceId),
+            JaegerDecoder::spanIdDecoder($spanId),
+            $flags
+        );
     }
 
     /**

tests/JaegerDecoderTest.php

@@ -0,0 +1,34 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * This file is part of Hyperf + OpenCodeCo
+ *
+ * @link     https://opencodeco.dev
+ * @document https://hyperf.wiki
+ * @contact  leo@opencodeco.dev
+ * @license  https://github.com/opencodeco/hyperf-metric/blob/main/LICENSE
+ */
+namespace HyperfTest\Tracer\Support;
+
+use Hyperf\Tracer\Support\JaegerDecoder;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * @internal
+ * @coversNothing
+ */
+final class JaegerDecoderTest extends TestCase
+{
+    public function testTraceIdDecoder(): void
+    {
+        self::assertSame('34876401113185248764011131852473', JaegerDecoder::traceIdDecoder('348764011131852473'));
+        self::assertSame('a36b5a7dcb5f6a542976b89e952e69ab', JaegerDecoder::traceIdDecoder('a36b5a7dcb5f6a542976b89e952e69ab'));
+    }
+
+    public function testSpanIdDecoder(): void
+    {
+        self::assertSame('255d1b261e0fcbc3', JaegerDecoder::spanIdDecoder('2692338002764483523'));
+        self::assertSame('21c2405de0e90c56', JaegerDecoder::spanIdDecoder('21c2405de0e90c56'));
+    }
+}