Spring Boot Test if web server starts on a specific port

By mkyong | Updated: August 16, 2023

Viewed: 2,205 (+28 pv/w)

Tags: junit 5 server port spring boot unit test

Below is a Spring Boot Test example to test whether the web server started on port 8181.

P.S. Tested with Spring Boot 3 and JUnit 5.

server.port = 8181

package com.mkyong;

import org.junit.jupiter.api.Test;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.boot.test.web.server.LocalServerPort;

import static org.junit.jupiter.api.Assertions.assertEquals;

@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
public class WebServerTests {

  @LocalServerPort
  private int port;

  @Test
  public void testServerPort() {
      assertEquals(8181, port, "Server is not running on port 8181");
  }

}

• The @LocalServerPort annotation injects the actual web server port.

Download Source Code

References

• SpringDoc – LocalServerPort
• How to change the default port in Spring Boot
• Spring Boot hello world example