Use connection id in server log messages if possible

Issue: SPR-16966

Author: rstoyanchev

spring-web/src/main/java/org/springframework/http/server/reactive/AbstractServerHttpRequest.java

@@ -179,4 +179,13 @@ public SslInfo getSslInfo() {
 	 */
 	public abstract <T> T getNativeRequest();
 
+	/**
+	 * Return an id for the underlying connection, if available.
+	 * @since 5.1
+	 */
+	@Nullable
+	public String getConnectionId() {
+		return null;
+	}
+
 }

spring-web/src/main/java/org/springframework/http/server/reactive/DefaultServerHttpRequestBuilder.java

@@ -191,6 +191,9 @@ private static class MutatedServerHttpRequest extends AbstractServerHttpRequest
 
 		private final ServerHttpRequest originalRequest;
 
+		@Nullable
+		private final String requestId;
+
 
 		public MutatedServerHttpRequest(URI uri, @Nullable String contextPath,
 				HttpHeaders headers, String methodValue, MultiValueMap<String, HttpCookie> cookies,
@@ -203,6 +206,8 @@ public MutatedServerHttpRequest(URI uri, @Nullable String contextPath,
 			this.sslInfo = sslInfo != null ? sslInfo : originalRequest.getSslInfo();
 			this.body = body;
 			this.originalRequest = originalRequest;
+			this.requestId = originalRequest instanceof AbstractServerHttpRequest ?
+					((AbstractServerHttpRequest) originalRequest).getConnectionId() : null;
 		}
 
 		@Override
@@ -237,6 +242,11 @@ public Flux<DataBuffer> getBody() {
 		public <T> T getNativeRequest() {
 			return (T) this.originalRequest;
 		}
+
+		@Override
+		public String getConnectionId() {
+			return this.requestId;
+		}
 	}
 
 }

spring-web/src/main/java/org/springframework/http/server/reactive/ReactorServerHttpRequest.java

@@ -174,4 +174,10 @@ public <T> T getNativeRequest() {
 		return (T) this.request;
 	}
 
+	@Override
+	public String getConnectionId() {
+		return this.request instanceof Connection ?
+				((Connection) this.request).channel().id().asShortText() : null;
+	}
+
 }

spring-web/src/main/java/org/springframework/http/server/reactive/UndertowServerHttpRequest.java

@@ -44,6 +44,7 @@
 import org.springframework.util.Assert;
 import org.springframework.util.LinkedMultiValueMap;
 import org.springframework.util.MultiValueMap;
+import org.springframework.util.ObjectUtils;
 import org.springframework.util.StringUtils;
 
 /**
@@ -59,6 +60,8 @@ class UndertowServerHttpRequest extends AbstractServerHttpRequest {
 
 	private final RequestBodyPublisher body;
 
+	private final String connectionId;
+
 
 	public UndertowServerHttpRequest(HttpServerExchange exchange, DataBufferFactory bufferFactory)
 			throws URISyntaxException {
@@ -67,6 +70,7 @@ public UndertowServerHttpRequest(HttpServerExchange exchange, DataBufferFactory
 		this.exchange = exchange;
 		this.body = new RequestBodyPublisher(exchange, bufferFactory);
 		this.body.registerListeners(exchange);
+		this.connectionId = ObjectUtils.getIdentityHexString(this.exchange.getConnection());
 	}
 
 	private static URI initUri(HttpServerExchange exchange) throws URISyntaxException {
@@ -127,6 +131,11 @@ public <T> T getNativeRequest() {
 		return (T) this.exchange;
 	}
 
+	@Override
+	public String getConnectionId() {
+		return this.connectionId;
+	}
+
 
 	private static class RequestBodyPublisher extends AbstractListenerReadPublisher<DataBuffer> {
 

spring-web/src/main/java/org/springframework/web/server/adapter/HttpWebHandlerAdapter.java

@@ -29,6 +29,7 @@
 import org.springframework.http.HttpStatus;
 import org.springframework.http.codec.LoggingCodecSupport;
 import org.springframework.http.codec.ServerCodecConfigurer;
+import org.springframework.http.server.reactive.AbstractServerHttpRequest;
 import org.springframework.http.server.reactive.HttpHandler;
 import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.http.server.reactive.ServerHttpResponse;
@@ -215,10 +216,7 @@ public void afterPropertiesSet() {
 	public Mono<Void> handle(ServerHttpRequest request, ServerHttpResponse response) {
 
 		ServerWebExchange exchange = createExchange(request, response);
-
-		String logId = ObjectUtils.getIdentityHexString(request);
-		exchange.getAttributes().put(ServerWebExchange.LOG_ID_ATTRIBUTE, logId);
-
+		exchange.getAttributes().put(ServerWebExchange.LOG_ID_ATTRIBUTE, initLogId(request));
 		logExchange(exchange);
 
 		return getDelegate().handle(exchange)
@@ -232,6 +230,17 @@ protected ServerWebExchange createExchange(ServerHttpRequest request, ServerHttp
 				getCodecConfigurer(), getLocaleContextResolver(), this.applicationContext);
 	}
 
+	private String initLogId(ServerHttpRequest request) {
+		String logId = null;
+		if (request instanceof AbstractServerHttpRequest) {
+			logId = ((AbstractServerHttpRequest) request).getConnectionId();
+		}
+		if (logId == null) {
+			logId = ObjectUtils.getIdentityHexString(request);
+		}
+		return logId;
+	}
+
 	private void logExchange(ServerWebExchange exchange) {
 		if (logger.isDebugEnabled()) {
 			String logPrefix = exchange.getLogPrefix();