Spring Boot Test failing to autowire port with LocalServerPort annotation

Question

I am running Spring Boot 2.0.1 and Junit 5. I am trying to get port within an integration test . However the port value is always zero. I am not sure what could be causing it. I have tried changing web environment enum to random port but nothing seems to be working.

package com.example.demo;

import org.junit.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.boot.web.server.LocalServerPort;
import org.springframework.test.context.junit.jupiter.SpringExtension;
import static org.junit.jupiter.api.Assertions.assertNotEquals;

@ExtendWith(SpringExtension.class)
@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.DEFINED_PORT)
public class DemoApplicationTests {

@LocalServerPort
private int port;
@Test


public void printPort() throws Exception {
     assertNotEquals(port, 0);
}
}

The following is the pom (NB. only shows the dependencies)

<properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <junit-jupiter.version>5.2.0</junit-jupiter.version>
        <junit-platform.version>1.2.0</junit-platform.version>
    </properties>

    <dependencies>
         <dependency>
                <groupId>org.junit.platform</groupId>
                <artifactId>junit-platform-launcher</artifactId>
                <scope>test</scope>
                <version>${junit-platform.version}</version>
            </dependency>
            <dependency>
                <groupId>org.junit.platform</groupId>
                <artifactId>junit-platform-engine</artifactId>
                <scope>test</scope>
                <version>${junit-platform.version}</version>
            </dependency>
            <dependency>
                <groupId>org.junit.jupiter</groupId>
                <artifactId>junit-jupiter-api</artifactId>
                <scope>test</scope>
                <version>${junit-jupiter.version}</version>
            </dependency>
            <dependency>
                <groupId>org.junit.jupiter</groupId>
                <artifactId>junit-jupiter-engine</artifactId>
                <scope>test</scope>
                <version>${junit-jupiter.version}</version>
            </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

application.properties

server.port=8080

Answer 1

I had the same problem, this set of annotations below worked for me. Without @ContextConfiguration port was 0.

@ContextConfiguration
@RunWith(SpringRunner.class)
@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
public class TestBase {

@LocalServerPort
protected int port;

}

Answer 2

I had same problem. This solution worked for me:

@Service
public class TestService implements ApplicationListener<ServletWebServerInitializedEvent> {

   private int localPort;

   @Override
   public void onApplicationEvent(final ServletWebServerInitializedEvent event) {
       localPort = event.getWebServer().getPort();
   }
}

You can autowire this service or you can implement ApplicationListener directly in your test class. Just a warning - the localPort variable is initialized during application startup after the bean is completely ready, so it won't be available in @PostConstruct etc.

Answer 3

You're missing a dependency on spring-boot-starter-web.