@Value("${local.server.port}") not working in Spring boot 1.5

Question

I am upgrading Spring Boot from 1.3 to 1.5. For upgrading to 1.5 I have replaced

@SpringApplicationConfiguration(classes = TestConfig.class) @WebIntegrationTest

with

@SpringBootTest(classes = TestConfig.class)

Also, I am using

@Value("${local.server.port}") protected int port;

to get port number defined in application.properties file. I further use this port number to build a REST URL.

But after the upgrade I am getting the error below whereas the same works fine with 1.3 Spring Boot Test.

Caused by: java.lang.IllegalArgumentException: Could not resolve placeholder 'local.server.port' in value "${local.server.port}" at org.springframework.util.PropertyPlaceholderHelper.parseStringValue(PropertyPlaceholderHelper.java:174)

Am I missing any changes that I need to do for this to work.

Answer 1

You have to provide a value for webEnvironment. In your case DEFINED_PORT like this

@SpringBootTest(classes = App.class, webEnvironment = WebEnvironment.DEFINED_PORT)
public class YourTest {

  @LocalServerPort           // shorthand for @Value("${local.server.port}")
  private Integer port;
  ...
}

For details see: https://docs.spring.io/spring-boot/docs/current/reference/html/boot-features-testing.html#boot-features-testing-spring-boot-applications

Answer 2

Adding another alternate solution which I had elsewhere.

I had configured

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

and

@RunWith(SpringRunner.class)
@SpringBootTest(classes = App.class, webEnvironment = WebEnvironment.RANDOM_PORT)
public class YourTest {

  @LocalServerPort           // shorthand for @Value("${local.server.port}")
  private Integer port;
  ...
}

Thinking that was it, and still getting this error even when specifying web environment etc. My ${local.server.port} seemed to be always null.

After some time, I noticed that my Spring Boot startup message contained no notion of the port it was using, so apparently it really didn't listen to any port at all - which explained why it was null in the first place. Adding actual container implementation dependency:

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-jetty</artifactId>
    </dependency>

Caused this to appear on my logs:

2019-02-26 18:45:47.231  INFO 12504 --- [           main] o.s.b.web.embedded.jetty.JettyWebServer  : Jetty started on port(s) 43132 (http/1.1) with context path '/'

after which local.server.port and @LocalServerPort would also work.