Support random actuator port in SpringBootTest

This commit changes @SpringBootTest(randomPort = true) to
generate a random port for the actuator endpoints if the
management server runs on a different port from the main
server.

Closes gh-4424

spring-boot-project/spring-boot-test/src/main/java/org/springframework/boot/test/web/SpringBootTestRandomPortEnvironmentPostProcessor.java

@@ -0,0 +1,77 @@
+/*
+ * Copyright 2012-2018 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
+ *
+ *      http://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.boot.test.web;
+
+import java.util.Objects;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.env.EnvironmentPostProcessor;
+import org.springframework.core.env.ConfigurableEnvironment;
+import org.springframework.core.env.MapPropertySource;
+import org.springframework.test.context.support.TestPropertySourceUtils;
+
+/**
+ * {@link EnvironmentPostProcessor} implementation to start the management context on a
+ * random port if the main server's port is 0 and the management context is expected on a
+ * different port.
+ *
+ * @author Madhura Bhave
+ * @since 2.1.0
+ */
+public class SpringBootTestRandomPortEnvironmentPostProcessor
+		implements EnvironmentPostProcessor {
+
+	private static final String MANAGEMENT_PORT_PROPERTY = "management.server.port";
+
+	private static final String SERVER_PORT_PROPERTY = "server.port";
+
+	@Override
+	public void postProcessEnvironment(ConfigurableEnvironment environment,
+			SpringApplication application) {
+		MapPropertySource source = (MapPropertySource) environment.getPropertySources()
+				.get(TestPropertySourceUtils.INLINED_PROPERTIES_PROPERTY_SOURCE_NAME);
+		if (isTestServerPortRandom(source)) {
+			if (source.getProperty(MANAGEMENT_PORT_PROPERTY) == null) {
+				String managementPort = getPort(environment, MANAGEMENT_PORT_PROPERTY,
+						null);
+				String serverPort = getPort(environment, SERVER_PORT_PROPERTY, "8080");
+				if (managementPort != null && !managementPort.equals("-1")) {
+					if (!managementPort.equals(serverPort)) {
+						source.getSource().put(MANAGEMENT_PORT_PROPERTY, "0");
+					}
+					else {
+						source.getSource().put(MANAGEMENT_PORT_PROPERTY, "");
+					}
+				}
+			}
+		}
+
+	}
+
+	private boolean isTestServerPortRandom(MapPropertySource source) {
+		return (source != null && "0".equals(source.getProperty(SERVER_PORT_PROPERTY)));
+	}
+
+	private String getPort(ConfigurableEnvironment environment, String property,
+			String defaultValue) {
+		return environment.getPropertySources().stream()
+				.filter((source) -> !source.getName().equals(
+						TestPropertySourceUtils.INLINED_PROPERTIES_PROPERTY_SOURCE_NAME))
+				.map((source) -> (String) source.getProperty(property))
+				.filter(Objects::nonNull).findFirst().orElse(defaultValue);
+	}
+
+}

spring-boot-project/spring-boot-test/src/main/resources/META-INF/spring.factories

@@ -11,3 +11,7 @@ org.springframework.boot.test.web.reactive.server.WebTestClientContextCustomizer
 org.springframework.test.context.TestExecutionListener=\
 org.springframework.boot.test.mock.mockito.MockitoTestExecutionListener,\
 org.springframework.boot.test.mock.mockito.ResetMocksTestExecutionListener
+
+# Environment Post Processors
+org.springframework.boot.env.EnvironmentPostProcessor=\
+org.springframework.boot.test.web.SpringBootTestRandomPortEnvironmentPostProcessor