Spring does not return an message in an error response

Question

I have dockerized a SpringBoot application.

When the application is running in a container, it does not return an error message in an error response (500).

e.g.

{
    "timestamp": 1704495987474,
    "status": 500,
    "error": "Internal Server Error",
    "path": "/api/conferences/1/check_roles"
}

When the application is run on localhost, with "mvn spring-boot:run", it does return a message in an error response (500).

e.g.

{
    "timestamp": 1704496938120,
    "status": 500,
    "error": "Internal Server Error",
    "trace": "(Long message)",
    "message": "Authentication failed!",
    "path": "/api/conferences/1/check_roles"
}

Why could this be? I need this because of an error checking in FE, so that I could display the right information for the user.

I tried looking in the nginx config, that is running as a FE docker container with Angular application, but could not find anything.

I tried implementing a custom ExceptionHandler in Spring, but it did not help either.

Answer 1

I looked at custom error handling, per point 7., in this link: https://www.baeldung.com/exception-handling-for-rest-with-spring#bd-spring-boot

And I found this:

server.error.include-message: since version 2.3, Spring Boot hides the message field in the response to avoid leaking sensitive information; we can use this property with an always value to enable it

It looks like this in my .yml config file:

server:
  error:
    include-message: always