Add CorrelationIdMiddleware

Author: bilfeldt

CHANGELOG.md

@@ -10,6 +10,10 @@ No breaking changes. The only changes are to the development dependencies used f
 
 ## Changes
 
+### 2.2.0 - 2023-08-29
+
+- Add middleware for adding 'Correlation-ID' header to responses
+
 ### 2.1.0 - 2023-07-24
 
 - Add support for PHP 8.1

src/Middleware/CorrelationIdMiddleware.php

@@ -0,0 +1,25 @@
+<?php
+
+namespace Bilfeldt\RequestLogger\Middleware;
+
+use Closure;
+use Illuminate\Http\Request;
+
+class CorrelationIdMiddleware
+{
+    /**
+     * Handle an incoming request.
+     *
+     * @param  \Illuminate\Http\Request  $request
+     * @param  \Closure  $next
+     * @return mixed
+     */
+    public function handle(Request $request, Closure $next)
+    {
+        $response = $next($request);
+
+        $response->headers->set('Correlation-ID', $request->getUniqueId(), true); // This is available on all Response types whereas $request->header() is only available in \Illuminate\Http\Response
+
+        return $response;
+    }
+}

tests/Unit/CorrelationIdMiddlewareTest.php

@@ -0,0 +1,25 @@
+<?php
+
+namespace Bilfeldt\RequestLogger\Tests\Unit;
+
+use Bilfeldt\RequestLogger\Middleware\CorrelationIdMiddleware;
+use Bilfeldt\RequestLogger\Tests\TestCase;
+use Illuminate\Http\Request;
+use Illuminate\Http\Response;
+
+class CorrelationIdMiddlewareTest extends TestCase
+{
+    public function test_adds_response_header(): void
+    {
+        $this->assertEquals('Correlation-ID', config('request-logger.header'));
+
+        $request = new Request();
+
+        $response1 = (new CorrelationIdMiddleware())->handle($request, function ($request) {
+            return new Response();
+        });
+
+        $this->assertTrue($response1->headers->has('Correlation-ID'));
+        $this->assertEquals($request->getUniqueId(), $response1->headers->get('Correlation-ID'));
+    }
+}