Polish Event Name

Provide a name with no spaces separate from the human-friendly
one with spaces.

Closes gh-12490

web/src/main/java/org/springframework/security/web/ObservationFilterChainDecorator.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2023 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.
@@ -182,7 +182,7 @@ public final class ObservationFilterChainDecorator implements FilterChainProxy.F
 				parentBefore.setFilterName(this.name);
 				parentBefore.setChainPosition(this.position);
 			}
-			parent.before().event(Observation.Event.of(this.name + " before"));
+			parent.before().event(Observation.Event.of(this.name + ".before", "before " + this.name));
 			this.filter.doFilter(request, response, chain);
 			parent.start();
 			if (parent.after().getContext() instanceof FilterChainObservationContext parentAfter) {
@@ -190,7 +190,7 @@ public final class ObservationFilterChainDecorator implements FilterChainProxy.F
 				parentAfter.setFilterName(this.name);
 				parentAfter.setChainPosition(this.size - this.position + 1);
 			}
-			parent.after().event(Observation.Event.of(this.name + " after"));
+			parent.after().event(Observation.Event.of(this.name + ".after", "after " + this.name));
 		}
 
 		private AroundFilterObservation parent(HttpServletRequest request) {

web/src/test/java/org/springframework/security/web/ObservationFilterChainDecoratorTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2023 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.
@@ -16,17 +16,24 @@
 
 package org.springframework.security.web;
 
+import java.util.List;
+
+import io.micrometer.observation.Observation;
 import io.micrometer.observation.ObservationHandler;
 import io.micrometer.observation.ObservationRegistry;
+import jakarta.servlet.Filter;
 import jakarta.servlet.FilterChain;
 import org.junit.jupiter.api.Test;
+import org.mockito.ArgumentCaptor;
 
 import org.springframework.mock.web.MockHttpServletRequest;
 import org.springframework.mock.web.MockHttpServletResponse;
 
+import static org.assertj.core.api.Assertions.assertThat;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.verifyNoInteractions;
 
@@ -61,4 +68,23 @@ public class ObservationFilterChainDecoratorTests {
 		verifyNoInteractions(handler);
 	}
 
+	@Test
+	void decorateFiltersWhenDefaultsThenObserves() throws Exception {
+		ObservationHandler<?> handler = mock(ObservationHandler.class);
+		given(handler.supportsContext(any())).willReturn(true);
+		ObservationRegistry registry = ObservationRegistry.create();
+		registry.observationConfig().observationHandler(handler);
+		ObservationFilterChainDecorator decorator = new ObservationFilterChainDecorator(registry);
+		FilterChain chain = mock(FilterChain.class);
+		Filter filter = mock(Filter.class);
+		FilterChain decorated = decorator.decorate(chain, List.of(filter));
+		decorated.doFilter(new MockHttpServletRequest("GET", "/"), new MockHttpServletResponse());
+		verify(handler, times(2)).onStart(any());
+		ArgumentCaptor<Observation.Event> event = ArgumentCaptor.forClass(Observation.Event.class);
+		verify(handler, times(2)).onEvent(event.capture(), any());
+		List<Observation.Event> events = event.getAllValues();
+		assertThat(events.get(0).getName()).isEqualTo(filter.getClass().getSimpleName() + ".before");
+		assertThat(events.get(1).getName()).isEqualTo(filter.getClass().getSimpleName() + ".after");
+	}
+
 }