Merge branch '6.1.x'

spring-web/src/main/java/org/springframework/web/filter/ServerHttpObservationFilter.java

@@ -119,13 +119,13 @@ public class ServerHttpObservationFilter extends OncePerRequestFilter {
 			throw ex;
 		}
 		finally {
-			// If async is started, register a listener for completion notification.
-			if (request.isAsyncStarted()) {
+			// If async is started during the first dispatch, register a listener for completion notification.
+			if (request.isAsyncStarted() && request.getDispatcherType() == DispatcherType.REQUEST) {
 				request.getAsyncContext().addListener(new ObservationAsyncListener(observation));
 			}
 			// scope is opened for ASYNC dispatches, but the observation will be closed
 			// by the async listener.
-			else if (request.getDispatcherType() != DispatcherType.ASYNC){
+			else if (!isAsyncDispatch(request)) {
 				Throwable error = fetchException(request);
 				if (error != null) {
 					observation.error(error);
@@ -180,6 +180,7 @@ public class ServerHttpObservationFilter extends OncePerRequestFilter {
 
 		@Override
 		public void onStartAsync(AsyncEvent event) {
+			event.getAsyncContext().addListener(this);
 		}
 
 		@Override

spring-web/src/test/java/org/springframework/web/filter/ServerHttpObservationFilterTests.java

@@ -22,11 +22,16 @@ import io.micrometer.observation.Observation;
 import io.micrometer.observation.ObservationRegistry;
 import io.micrometer.observation.tck.TestObservationRegistry;
 import io.micrometer.observation.tck.TestObservationRegistryAssert;
+import jakarta.servlet.AsyncContext;
 import jakarta.servlet.AsyncEvent;
 import jakarta.servlet.AsyncListener;
 import jakarta.servlet.DispatcherType;
+import jakarta.servlet.Filter;
+import jakarta.servlet.FilterChain;
 import jakarta.servlet.RequestDispatcher;
 import jakarta.servlet.ServletException;
+import jakarta.servlet.ServletRequest;
+import jakarta.servlet.ServletResponse;
 import jakarta.servlet.http.HttpServlet;
 import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
@@ -149,6 +154,21 @@ class ServerHttpObservationFilterTests {
 		assertThatHttpObservation().hasLowCardinalityKeyValue("outcome", "SUCCESS").hasBeenStopped();
 	}
 
+	@Test
+	void shouldRegisterListenerForAsyncStarts() throws Exception {
+		CustomAsyncFilter customAsyncFilter = new CustomAsyncFilter();
+		this.mockFilterChain = new MockFilterChain(new NoOpServlet(), customAsyncFilter);
+		this.request.setAsyncSupported(true);
+		this.request.setDispatcherType(DispatcherType.REQUEST);
+		this.filter.doFilter(this.request, this.response, this.mockFilterChain);
+		customAsyncFilter.asyncContext.dispatch();
+		this.request.setDispatcherType(DispatcherType.ASYNC);
+		AsyncContext newAsyncContext = this.request.startAsync();
+		newAsyncContext.complete();
+
+		assertThatHttpObservation().hasLowCardinalityKeyValue("outcome", "SUCCESS").hasBeenStopped();
+	}
+
 	@Test
 	void shouldCloseObservationAfterAsyncError() throws Exception {
 		this.request.setAsyncSupported(true);
@@ -210,6 +230,29 @@ class ServerHttpObservationFilterTests {
 			Assert.notNull(response, "response must not be null");
 			response.setHeader("X-Trace-Id", "badc0ff33");
 		}
+
+	}
+
+	@SuppressWarnings("serial")
+	static class NoOpServlet extends HttpServlet {
+
+		@Override
+		protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+
+		}
+
+	}
+
+	static class CustomAsyncFilter implements Filter {
+
+		AsyncContext asyncContext;
+
+		@Override
+		public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
+			this.asyncContext = servletRequest.startAsync();
+			filterChain.doFilter(servletRequest, servletResponse);
+		}
+
 	}
 
 }

spring-web/src/testFixtures/java/org/springframework/web/testfixture/servlet/MockHttpServletRequest.java

@@ -44,6 +44,8 @@ import java.util.TimeZone;
 import java.util.stream.Collectors;
 
 import jakarta.servlet.AsyncContext;
+import jakarta.servlet.AsyncEvent;
+import jakarta.servlet.AsyncListener;
 import jakarta.servlet.DispatcherType;
 import jakarta.servlet.RequestDispatcher;
 import jakarta.servlet.ServletConnection;
@@ -920,7 +922,19 @@ public class MockHttpServletRequest implements HttpServletRequest {
 	public AsyncContext startAsync(ServletRequest request, @Nullable ServletResponse response) {
 		Assert.state(this.asyncSupported, "Async not supported");
 		this.asyncStarted = true;
-		this.asyncContext = new MockAsyncContext(request, response);
+		MockAsyncContext newAsyncContext = new MockAsyncContext(request, response);
+		if (this.asyncContext != null) {
+			try {
+				AsyncEvent startEvent = new AsyncEvent(newAsyncContext);
+				for (AsyncListener asyncListener : this.asyncContext.getListeners()) {
+					asyncListener.onStartAsync(startEvent);
+				}
+			}
+			catch (IOException ex) {
+				// ignore failures
+			}
+		}
+		this.asyncContext = newAsyncContext;
 		return this.asyncContext;
 	}