feat: add support for injecting into an array (#23)

contributors: @eddycharly
auxmoney · Mar 13, 2020 · 10417e6 · 10417e6
1 parent 7e2bc45
commit 10417e6
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Showing 5 changed files with 78 additions and 8 deletions.
diff --git a/README.md b/README.md
@@ -90,6 +90,14 @@ If you do not use Guzzle, you need to inject the trace headers into every outgoi
 
 on the request and use the resulting request with your favorite request client.
 
+If you are using a request that is not PSR-7 compatible, you can inject the headers directly into an array using
+
+```php
+    Auxmoney\OpentracingBundle\Service\Tracing::injectTracingHeadersIntoCarrier(array $carrier): array
+```
+
+passing the array representing the headers of your request.
+
 ### Automatic tracing
 
 Out of the box, the bundle will trace some spans automatically:

diff --git a/Service/Tracing.php b/Service/Tracing.php
@@ -4,10 +4,20 @@
 
 namespace Auxmoney\OpentracingBundle\Service;
 
+use OpenTracing\Exceptions\UnsupportedFormat;
 use Psr\Http\Message\RequestInterface;
 
 interface Tracing
 {
+    /**
+     * Injects necessary tracing headers into an array.
+     * @param array<mixed> $carrier
+     * @return array<mixed>
+     *
+     * @throws UnsupportedFormat when the format is not recognized by the tracer
+     */
+    public function injectTracingHeadersIntoCarrier(array $carrier): array;
+
     /**
      * Injects necessary tracing headers into a RequestInterface.
      *

diff --git a/Service/TracingService.php b/Service/TracingService.php
@@ -7,7 +7,9 @@
 use Auxmoney\OpentracingBundle\Internal\Opentracing;
 use Psr\Http\Message\RequestInterface;
 use Psr\Log\LoggerInterface;
+use OpenTracing\Exceptions\UnsupportedFormat;
 use const OpenTracing\Formats\TEXT_MAP;
+use OpenTracing\Span;
 
 final class TracingService implements Tracing
 {
@@ -20,22 +22,33 @@ public function __construct(Opentracing $opentracing, LoggerInterface $logger)
         $this->logger = $logger;
     }
 
+    public function injectTracingHeadersIntoCarrier(array $carrier): array
+    {
+        $span = $this->tracer->getActiveSpan();
+
+        if (!$span) {
+            $this->logger->warning(self::class . ': could not inject tracing headers, missing active span');
+            return $carrier;
+        }
+
+        return $this->doInjectTracingHeadersIntoCarrier($span, $carrier);
+    }
+
     public function injectTracingHeaders(RequestInterface $request): RequestInterface
     {
-        if (!$this->tracer->getActiveSpan()) {
+        $span = $this->tracer->getActiveSpan();
+
+        if (!$span) {
             $this->logger->warning(self::class . ': could not inject tracing headers, missing active span');
             return $request;
         }
 
-        $headers = [];
-        $this->tracer->inject(
-            $this->tracer->getActiveSpan()->getContext(),
-            TEXT_MAP,
-            $headers
-        );
+        $headers = $this->doInjectTracingHeadersIntoCarrier($span, []);
+
         foreach ($headers as $headerKey => $headerValue) {
             $request = $request->withHeader($headerKey, $headerValue);
         }
+
         return $request;
     }
 
@@ -78,4 +91,17 @@ public function finishActiveSpan(): void
 
         $this->tracer->getScopeManager()->getActive()->close();
     }
+
+    /**
+     * Injects necessary tracing headers into an array.
+     * @param array<mixed> $carrier
+     * @return array<mixed>
+     *
+     * @throws UnsupportedFormat when the format is not recognized by the tracer
+     */
+    private function doInjectTracingHeadersIntoCarrier(Span $span, array $carrier): array
+    {
+        $this->tracer->inject($span->getContext(), TEXT_MAP, $carrier);
+        return $carrier;
+    }
 }
diff --git a/Tests/Mock/MockTracer.php b/Tests/Mock/MockTracer.php
@@ -49,7 +49,7 @@ public function startSpan($operationName, $options = [])
      */
     public function inject(SpanContext $spanContext, $format, &$carrier)
     {
-        $carrier = ['made_up_header' => '1:2:3:4'];
+        $carrier['made_up_header'] = '1:2:3:4';
     }
 
     public function extract($format, $carrier)

diff --git a/Tests/Service/TracingServiceTest.php b/Tests/Service/TracingServiceTest.php
@@ -45,6 +45,19 @@ public function testInjectTracingHeadersSuccess(): void
         self::assertSame($newRequest->reveal(), $injectedRequest);
     }
 
+    public function testInjectTracingHeadersIntoCarrierSuccess(): void
+    {
+        $this->mockTracer->startActiveSpan('test span');
+
+        $headers = [ 'abc' => '123' ];
+
+        $this->logger->warning(Argument::type('string'))->shouldNotBeCalled();
+
+        $newHeaders = $this->subject->injectTracingHeadersIntoCarrier($headers);
+        self::assertSame([ 'abc' => '123' ], $headers);
+        self::assertSame([ 'abc' => '123', 'made_up_header' => '1:2:3:4' ], $newHeaders);
+    }
+
     public function testInjectTracingHeadersNoActiveSpan(): void
     {
         $originalRequest = $this->prophesize(RequestInterface::class);
@@ -56,6 +69,19 @@ public function testInjectTracingHeadersNoActiveSpan(): void
         self::assertSame($originalRequest->reveal(), $injectedRequest);
     }
 
+    public function testInjectTracingHeadersIntoCarrierNoActiveSpan(): void
+    {
+        $originalRequest = $this->prophesize(RequestInterface::class);
+
+        $headers = [ 'abc' => '123' ];
+
+        $this->logger->warning(Argument::type('string'))->shouldBeCalled();
+
+        $newHeaders = $this->subject->injectTracingHeadersIntoCarrier($headers);
+        self::assertSame([ 'abc' => '123' ], $headers);
+        self::assertSame($headers, $newHeaders);
+    }
+
     public function testStartActiveSpanWithoutOptionsSuccess(): void
     {
         $this->subject->startActiveSpan('operation name');