Question: Route stops working after upgrading to Spring Boot 4.0.1

[atolini]

I have a Spring Boot application running on 3.5.9 where an MVC gateway route defined in application.yml works as expected. After upgrading the app to Spring Boot 4.0.1 the same route no longer matches requests. The route only works when I register it programmatically via the API.

What I expected

After upgrading to Spring Boot 4.0.1 the YAML-configured gateway route keeps working the same way as on 3.5.9.

What actually happens

The route defined in YAML does not match requests anymore.
The same route works when created programmatically at runtime via the gateway API.
Configuration (application.yml)

spring:
  application:
    name: trainee-gateway
  cloud:
    gateway:
      mvc:
        routes:
          - id: list-attendances
            uri: https://a3962389-cd14-4907-a577-8c22b4d0e923.mock.pstmn.io
            predicates:
              - Path=/attendances
              - Method=GET    

Notes / additional context

• This configuration worked on Spring Boot 3.5.9.
• After migrating to Spring Boot 4.0.1 the route no longer matches; there are no (obvious) startup errors.
• I’m using the MVC gateway configuration (spring.cloud.gateway.mvc.*) rather than the reactive gateway.

[ryanjbaxter]

The properties changed, can you try spring.cloud.gateway.server.webmvc.routes instead?

[atolini]

It worked, thank you!