Spring Boot Google App Engine security annotation? - spring-boot

Question

I'm currently working on a Spring Boot project with Google App Engine & I'm trying to check if my user is logged in on my controller actions thanks to annotations, like #PreAuthorize(isAuthenticated()). This annotation would return a HTTP 403 error if false.
Currently, my users are logged in with the Google App Engine basic UserService & I already tried to use this annotation without success (it does nothing).
Here is my pom file :
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-tomcat</artifactId>
<version>2.1.3.RELEASE</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<version>2.1.3.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<version>2.1.3.RELEASE</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
<version>2.1.3.RELEASE</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>4.0.1</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>com.google.cloud</groupId>
<artifactId>google-cloud</artifactId>
<version>0.47.0-alpha</version>
</dependency>
<dependency>
<groupId>org.webjars</groupId>
<artifactId>jquery</artifactId>
<version>3.3.1-2</version>
</dependency>
<dependency>
<groupId>org.webjars</groupId>
<artifactId>materializecss</artifactId>
<version>1.0.0</version>
</dependency>
<dependency>
<groupId>com.google.appengine</groupId>
<artifactId>appengine-api-1.0-sdk</artifactId>
<version>1.9.71</version>
</dependency>
I'm trying to make my code more readable currently I'm doing this on my controller :
private UserService userService = UserServiceFactory.getUserService();
#GetMapping("/pizza/create")
public String createPizza(Model model) {
if (!userService.isUserLoggedIn()) { // used in every actions that need an authentication check
return "error";
}
model.addAttribute("pizza", new Pizza());
return "create";
}
But I'd like to have this :
#PreAuthorize(isAuthenticated())
#GetMapping("/pizza/create")
public String createPizza(Model model) {
model.addAttribute("pizza", new Pizza());
return "create";
}