Append unique number to WebFlux server log prefix

Closes gh-22039

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,6 +19,7 @@ package org.springframework.http.server.reactive;
 import java.net.InetSocketAddress;
 import java.net.URI;
 import java.net.URISyntaxException;
+import java.util.concurrent.atomic.AtomicLong;
 
 import javax.net.ssl.SSLSession;
 
@@ -47,6 +48,9 @@ import org.springframework.util.MultiValueMap;
  */
 class ReactorServerHttpRequest extends AbstractServerHttpRequest {
 
+	private static final AtomicLong logPrefixIndex = new AtomicLong(0);
+
+
 	private final HttpServerRequest request;
 
 	private final NettyDataBufferFactory bufferFactory;
@@ -181,8 +185,11 @@ class ReactorServerHttpRequest extends AbstractServerHttpRequest {
 	@Override
 	@Nullable
 	protected String initId() {
-		return this.request instanceof Connection ?
-				((Connection) this.request).channel().id().asShortText() : null;
+		if (this.request instanceof Connection) {
+			return ((Connection) this.request).channel().id().asShortText() +
+					"-" + logPrefixIndex.incrementAndGet();
+		}
+		return null;
 	}
 
 }