Enable cache when a SecurityContext parameter is used

This commit restores caching for the main read operation when the
SecurityContext does not expose a principal (i.e. guest access).

Closes gh-13238

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/invoker/cache/CachingOperationInvokerAdvisor.java

@@ -19,8 +19,10 @@ package org.springframework.boot.actuate.endpoint.invoker.cache;
 import java.util.function.Function;
 
 import org.springframework.boot.actuate.endpoint.OperationType;
+import org.springframework.boot.actuate.endpoint.SecurityContext;
 import org.springframework.boot.actuate.endpoint.invoke.OperationInvoker;
 import org.springframework.boot.actuate.endpoint.invoke.OperationInvokerAdvisor;
+import org.springframework.boot.actuate.endpoint.invoke.OperationParameter;
 import org.springframework.boot.actuate.endpoint.invoke.OperationParameters;
 
 /**
@@ -40,7 +42,7 @@ public class CachingOperationInvokerAdvisor implements OperationInvokerAdvisor {
 	@Override
 	public OperationInvoker apply(String endpointId, OperationType operationType,
 			OperationParameters parameters, OperationInvoker invoker) {
-		if (operationType == OperationType.READ && !parameters.hasMandatoryParameter()) {
+		if (operationType == OperationType.READ && !hasMandatoryParameter(parameters)) {
 			Long timeToLive = this.endpointIdTimeToLive.apply(endpointId);
 			if (timeToLive != null && timeToLive > 0) {
 				return new CachingOperationInvoker(invoker, timeToLive);
@@ -49,4 +51,14 @@ public class CachingOperationInvokerAdvisor implements OperationInvokerAdvisor {
 		return invoker;
 	}
 
+	private boolean hasMandatoryParameter(OperationParameters parameters) {
+		for (OperationParameter parameter : parameters) {
+			if (parameter.isMandatory()
+					&& !SecurityContext.class.isAssignableFrom(parameter.getType())) {
+				return true;
+			}
+		}
+		return false;
+	}
+
 }

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/invoker/cache/CachingOperationInvokerAdvisorTests.java

@@ -25,6 +25,7 @@ import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 
 import org.springframework.boot.actuate.endpoint.OperationType;
+import org.springframework.boot.actuate.endpoint.SecurityContext;
 import org.springframework.boot.actuate.endpoint.invoke.OperationInvoker;
 import org.springframework.boot.actuate.endpoint.invoke.OperationParameters;
 import org.springframework.boot.actuate.endpoint.invoke.reflect.OperationMethod;
@@ -111,6 +112,14 @@ public class CachingOperationInvokerAdvisorTests {
 		assertAdviseIsApplied(parameters);
 	}
 
+	@Test
+	public void applyWithSecurityContextShouldAddAdvise() {
+		OperationParameters parameters = getParameters("getWithSecurityContext",
+				SecurityContext.class, String.class);
+		given(this.timeToLive.apply(any())).willReturn(100L);
+		assertAdviseIsApplied(parameters);
+	}
+
 	private void assertAdviseIsApplied(OperationParameters parameters) {
 		OperationInvoker advised = this.advisor.apply("foo", OperationType.READ,
 				parameters, this.invoker);
@@ -147,6 +156,11 @@ public class CachingOperationInvokerAdvisorTests {
 			return "";
 		}
 
+		public String getWithSecurityContext(SecurityContext securityContext,
+				@Nullable String bar) {
+			return "";
+		}
+
 	}
 
 }

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/invoker/cache/CachingOperationInvokerTests.java

@@ -16,6 +16,7 @@
 
 package org.springframework.boot.actuate.endpoint.invoker.cache;
 
+import java.security.Principal;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
@@ -96,6 +97,21 @@ public class CachingOperationInvokerTests {
 		verify(target, times(3)).invoke(context);
 	}
 
+	@Test
+	public void targetAlwaysInvokedWithPrincipal() {
+		OperationInvoker target = mock(OperationInvoker.class);
+		Map<String, Object> parameters = new HashMap<>();
+		SecurityContext securityContext = mock(SecurityContext.class);
+		given(securityContext.getPrincipal()).willReturn(mock(Principal.class));
+		InvocationContext context = new InvocationContext(securityContext, parameters);
+		given(target.invoke(context)).willReturn(new Object());
+		CachingOperationInvoker invoker = new CachingOperationInvoker(target, 500L);
+		invoker.invoke(context);
+		invoker.invoke(context);
+		invoker.invoke(context);
+		verify(target, times(3)).invoke(context);
+	}
+
 	@Test
 	public void targetInvokedWhenCacheExpires() throws InterruptedException {
 		OperationInvoker target = mock(OperationInvoker.class);