Spring WebFlux Request Principal is null in test - spring-boot

Question

We have library which provides a custom filter for our requests, which we use to write information on the request to our logs. We previously only needed servlet support, but now need to add webflux support. I've created a new WebFilter, which works as expected.
However, trying to test this new filter has been difficult. We're relying on the principal in the request for user information for the log, but during the test, it is always null. I've tried many things, including following the examples here: https://docs.spring.io/spring-security/site/docs/5.1.0.RELEASE/reference/html/test-webflux.html
My Filter:
package com.project.utils.security.request.logging.config.autoconfig;
import com.project.utils.logging.LoggingUtil;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.server.ServerWebExchange;
import org.springframework.web.server.WebFilter;
import org.springframework.web.server.WebFilterChain;
import reactor.core.publisher.Mono;
public class ReactiveRequestLoggingFilter implements WebFilter {
private static final Logger logger = LoggerFactory.getLogger(ReactiveRequestLoggingFilter.class);
#Override
public Mono<Void> filter(ServerWebExchange serverWebExchange, WebFilterChain webFilterChain) {
return serverWebExchange
.getPrincipal()
.flatMap(
principal -> {
LoggingUtil loggingUtil =
new LoggingUtil(serverWebExchange.getRequest(), principal.getName());
loggingUtil.setEvent("Http Request");
logger.info(loggingUtil.toString());
return webFilterChain.filter(serverWebExchange);
});
}
}
My Test:
package com.project.utils.security.request.logging.config.autoconfig;
import static org.springframework.security.test.web.reactive.server.SecurityMockServerConfigurers.mockUser;
import static org.springframework.security.test.web.reactive.server.SecurityMockServerConfigurers.springSecurity;
import com.project.utils.security.request.logging.config.testcontrollers.ReactiveTestController;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit.jupiter.SpringExtension;
import org.springframework.test.web.reactive.server.WebTestClient;
#ExtendWith(SpringExtension.class)
#SpringBootTest(classes = {ReactiveTestController.class})
class ReactiveRequestLoggingFilterTest {
#Autowired ReactiveTestController controller;
ReactiveRequestLoggingFilter filter = new ReactiveRequestLoggingFilter();
#Test
void test() {
WebTestClient client =
WebTestClient.bindToController(controller)
.webFilter(filter)
.apply(springSecurity())
.configureClient()
.build()
.mutateWith(mockUser("User"));
client
.get()
.uri("/test")
.exchange()
.expectStatus()
.isOk()
.expectBody(String.class)
.isEqualTo("GET");
}
}
The controller I'm using for the test:
package com.project.utils.security.request.logging.config.testcontrollers;
import com.project.utils.security.request.logging.config.annotations.EnableReactiveRequestLogging;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import reactor.core.publisher.Mono;
#RestController
#RequestMapping("/test")
#EnableReactiveRequestLogging
public class ReactiveTestController {
#GetMapping
Mono<ResponseEntity<String>> get() {
return Mono.just(ResponseEntity.ok("GET"));
}
}
We are using Spring Boot 2.1, which uses Spring Security 5.1. Like I said, the actual functionality works, but we need to get tests written for it, and I can't figure out how to get the principal into the request.
Thanks!

Answer 1

Okay, found a working solution from this answer: https://stackoverflow.com/a/55426458/1370823
My final test looked like:
package com.project.utils.security.request.logging.config.autoconfig;
import static org.springframework.security.test.web.reactive.server.SecurityMockServerConfigurers.springSecurity;
import com.project.utils.security.request.logging.config.testcontrollers.ReactiveTestController;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.web.reactive.WebFluxTest;
import org.springframework.security.test.context.support.WithMockUser;
import org.springframework.security.web.server.context.SecurityContextServerWebExchangeWebFilter;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit.jupiter.SpringExtension;
import org.springframework.test.web.reactive.server.WebTestClient;
#ExtendWith(SpringExtension.class)
#ContextConfiguration(classes = {ReactiveTestController.class, ReactiveRequestLoggingFilter.class})
#WebFluxTest(controllers = {ReactiveTestController.class})
#WithMockUser(value = "Test User", username = "TestUser")
class ReactiveRequestLoggingFilterTest {
#Autowired ReactiveTestController controller;
#Autowired ReactiveRequestLoggingFilter filter;
#Test
void test() {
WebTestClient client =
WebTestClient.bindToController(controller)
.webFilter(new SecurityContextServerWebExchangeWebFilter())
.webFilter(filter)
.apply(springSecurity())
.build();
client
.get()
.uri("/test")
.exchange()
.expectStatus()
.isOk()
.expectBody(String.class)
.isEqualTo("GET");
}
}