fix: make middleware injection idempotent and header lookups case-insensitive

lib/Http/Client/LoggingClientService.php

@@ -40,9 +40,13 @@ public function newClient(?callable $handler = null): IClient {
 			/** @var \GuzzleHttp\Client $guzzle */
 			$guzzle = $ref->getValue($client);
 
-			$handler = $guzzle->getConfig('handler');
-			if ($handler instanceof \GuzzleHttp\HandlerStack) {
-				$handler->unshift(
+			$stack = $guzzle->getConfig('handler');
+			if ($stack instanceof \GuzzleHttp\HandlerStack) {
+				// Idempotent: replace an already injected entry instead of
+				// stacking a second one (double decoration would silently
+				// duplicate every log entry).
+				$stack->remove('admin_audit_http_client');
+				$stack->unshift(
 					new HttpClientLoggerMiddleware(
 						$this->logger,
 						$this->resolveLogDir(),

lib/Http/Client/Middleware/HttpClientLoggerMiddleware.php

@@ -129,8 +129,13 @@ function (ResponseInterface $response) use ($request, $reqHeaders, $reqId) {
 
 						// Content-Length: 0 — no body
 						if (!$immediate) {
-							$compact = $this->compactHeaders($respHeaders);
-							$cl = $compact['content-length'] ?? $compact['Content-Length'] ?? null;
+							$cl = null;
+							foreach ($meta['responseHeaders'] as $k => $v) {
+								if (strtolower((string)$k) === 'content-length') {
+									$cl = is_array($v) ? ($v[0] ?? null) : $v;
+									break;
+								}
+							}
 							if ($cl !== null && is_numeric($cl) && (int)$cl === 0) {
 								$immediate = true;
 							}

lib/Http/Client/Middleware/LogPathHelper.php

@@ -34,15 +34,20 @@ public static function getPathsFromMeta(array $meta, string $baseDir, ?string $r
 			}
 		}
 
-		if ($host === null && !empty($meta['requestHeaders']['Host'])) {
-			$hostHeader = $meta['requestHeaders']['Host'];
-			$hostHeader = is_array($hostHeader) ? ($hostHeader[0] ?? '') : (string)$hostHeader;
-			if ($hostHeader !== '') {
-				if (strpos($hostHeader, ':') !== false) {
-					[$host, $port] = explode(':', $hostHeader, 2) + [1 => null];
-				} else {
-					$host = $hostHeader;
+		if ($host === null && !empty($meta['requestHeaders']) && is_array($meta['requestHeaders'])) {
+			foreach ($meta['requestHeaders'] as $name => $value) {
+				if (strtolower((string)$name) !== 'host') {
+					continue;
 				}
+				$hostHeader = is_array($value) ? ($value[0] ?? '') : (string)$value;
+				if ($hostHeader !== '') {
+					if (strpos($hostHeader, ':') !== false) {
+						[$host, $port] = explode(':', $hostHeader, 2) + [1 => null];
+					} else {
+						$host = $hostHeader;
+					}
+				}
+				break;
 			}
 		}
 

tests/integration/MiddlewareInjectionTest.php

@@ -44,7 +44,9 @@ public function testMiddlewareIsInjectedIntoHandlerStack(): void {
 
 		$stackRef = new \ReflectionProperty(HandlerStack::class, 'stack');
 		$names = array_column($stackRef->getValue($handler), 1);
-		$this->assertContains('admin_audit_http_client', $names);
+		// This service decorates the already decorated container service, so
+		// without the idempotency guard the entry would appear twice here.
+		$this->assertCount(1, array_keys($names, 'admin_audit_http_client', true));
 	}
 
 	public function testEnabledAppDecoratesClientService(): void {

tests/unit/Http/Client/Middleware/HttpClientLoggerMiddlewareTest.php

@@ -125,6 +125,32 @@ public function testGeneratedRequestIdCarriesServerRequestIdPrefix(): void {
 		$this->assertStringStartsWith('server-req-', (string)$seen);
 	}
 
+	public function testMixedCaseContentLengthZeroLogsImmediately(): void {
+		$dir = sys_get_temp_dir() . '/aahc-cl-' . bin2hex(random_bytes(4));
+		$mw = new HttpClientLoggerMiddleware(new NullLogger(), $dir);
+
+		$handler = $mw(function (Request $request, array $options) {
+			return new FulfilledPromise(new Response(200, ['Content-length' => '0'], ''));
+		});
+
+		try {
+			$response = $handler(new Request('GET', 'https://example.com/ping'), [])->wait();
+
+			$this->assertNotInstanceOf(CountingStream::class, $response->getBody());
+
+			$lines = file($dir . '/example.com.json', FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES);
+			$this->assertNotFalse($lines);
+			$entry = json_decode($lines[0], true, 512, JSON_THROW_ON_ERROR);
+			$this->assertSame(200, $entry['status']);
+			$this->assertNull($entry['compressionStats']['decompressed_bytes']);
+		} finally {
+			foreach (glob($dir . '/*') ?: [] as $file) {
+				@unlink($file);
+			}
+			@rmdir($dir);
+		}
+	}
+
 	public function testWriteImmediateOmitsDecompressedBytesAndRatio(): void {
 		$dir = sys_get_temp_dir() . '/aahc-wi-' . bin2hex(random_bytes(4));
 		$mw = new HttpClientLoggerMiddleware(new NullLogger(), $dir);

tests/unit/Http/Client/Middleware/LogPathHelperTest.php

@@ -55,6 +55,14 @@ public function testHostHeaderFallbackWithPort(): void {
 		$this->assertSame($this->baseDir . '/foo.bar_8080.json', $json);
 	}
 
+	public function testHostHeaderFallbackIsCaseInsensitive(): void {
+		[$json] = LogPathHelper::getPathsFromMeta(
+			['requestHeaders' => ['host' => 'foo.bar:8080']],
+			$this->baseDir,
+		);
+		$this->assertSame($this->baseDir . '/foo.bar_8080.json', $json);
+	}
+
 	public function testHostHeaderFallbackAcceptsArrayValues(): void {
 		[$json] = LogPathHelper::getPathsFromMeta(
 			['requestHeaders' => ['Host' => ['foo.bar']]],