GH-2253 Provide isolated ObjectMapper to BindingsLifecycleController

This is specifically to avoid any potetial interference from the user
Resolves #2253

spring-cloud-stream/src/main/java/org/springframework/cloud/stream/binding/BindingsLifecycleController.java

@@ -19,6 +19,7 @@ package org.springframework.cloud.stream.binding;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
+import java.util.Map;
 import java.util.stream.Stream;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
@@ -44,12 +45,13 @@ public class BindingsLifecycleController {
 	private final ObjectMapper objectMapper;
 
 	public BindingsLifecycleController(List<InputBindingLifecycle> inputBindingLifecycles,
-			List<OutputBindingLifecycle> outputBindingsLifecycles, ObjectMapper objectMapper) {
+			List<OutputBindingLifecycle> outputBindingsLifecycles) {
 		Assert.notEmpty(inputBindingLifecycles,
 				"'inputBindingLifecycles' must not be null or empty");
 		this.inputBindingLifecycles = inputBindingLifecycles;
 		this.outputBindingsLifecycles = outputBindingsLifecycles;
-		this.objectMapper = objectMapper;
+		this.objectMapper = new ObjectMapper(); //see https://github.com/spring-cloud/spring-cloud-stream/issues/2253
+		// we need to use ObjectMapper that could not be modified by the user.
 	}
 
 	/**
@@ -118,7 +120,7 @@ public class BindingsLifecycleController {
 	 * @return the list of {@link Binding}s
 	 */
 	@SuppressWarnings("unchecked")
-	public List<Binding<?>> queryStates() {
+	public List<Map<?, ?>> queryStates() {
 		List<Binding<?>> bindings = new ArrayList<>(gatherInputBindings());
 		bindings.addAll(gatherOutputBindings());
 		return this.objectMapper.convertValue(bindings, List.class);

spring-cloud-stream/src/main/java/org/springframework/cloud/stream/config/BindingServiceConfiguration.java

@@ -243,9 +243,8 @@ public class BindingServiceConfiguration {
 
 	@Bean
 	public BindingsLifecycleController bindingsLifecycleController(List<InputBindingLifecycle> inputBindingLifecycles,
-			List<OutputBindingLifecycle> outputBindingsLifecycles, @Nullable ObjectMapper objectMapper) {
-		objectMapper = objectMapper == null ? new ObjectMapper() : objectMapper;
-		return new BindingsLifecycleController(inputBindingLifecycles, outputBindingsLifecycles, objectMapper);
+			List<OutputBindingLifecycle> outputBindingsLifecycles) {
+		return new BindingsLifecycleController(inputBindingLifecycles, outputBindingsLifecycles);
 	}
 
 	@Bean

spring-cloud-stream/src/test/java/org/springframework/cloud/stream/endpoint/ActuatorBindingsTest.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright 2018-2021 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.cloud.stream.endpoint;
+
+import java.util.List;
+import java.util.Map;
+import java.util.function.Consumer;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.boot.WebApplicationType;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.builder.SpringApplicationBuilder;
+import org.springframework.cloud.stream.binder.test.TestChannelBinderConfiguration;
+import org.springframework.cloud.stream.binding.BindingsLifecycleController;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.context.annotation.Bean;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ *
+ */
+public class ActuatorBindingsTest {
+
+	/*
+	 * Even though this test performs some simple assertions, the main purpose for it is to validate that
+	 * it does not result in recursive exception described in https://github.com/spring-cloud/spring-cloud-stream/issues/2253
+	 */
+	@Test
+	public void test_2253() {
+		try (ConfigurableApplicationContext context = new SpringApplicationBuilder(
+				TestChannelBinderConfiguration.getCompleteConfiguration(Bindings.class))
+						.web(WebApplicationType.NONE).run("--spring.jmx.enabled=false",
+								"--spring.cloud.function.definition=consume",
+								"--spring.jackson.visibility.field=ANY" // see https://github.com/spring-cloud/spring-cloud-stream/issues/2253
+						// we need the above just to verify that such action does not
+						// interfere with instance of ObjectMapper inside of BindingsLifecycleController
+						)) {
+
+			BindingsLifecycleController controller = context
+					.getBean(BindingsLifecycleController.class);
+			List<Map<?, ?>> bindings = controller.queryStates();
+			assertThat(bindings.size()).isEqualTo(1);
+			assertThat(bindings.get(0).get("bindingName")).isEqualTo("consume-in-0");
+		}
+
+	}
+
+	@EnableAutoConfiguration
+	public static class Bindings {
+
+		@Bean
+		public Consumer<String> consume() {
+			return message -> System.out.println("Received message " + message);
+		}
+
+	}
+
+}