Constructor injection for BeanResolver

Author: rwinch

spring-graphql/src/main/java/org/springframework/graphql/data/method/annotation/support/AnnotatedControllerConfigurer.java

@@ -37,6 +37,7 @@
 import org.apache.commons.logging.LogFactory;
 import org.dataloader.DataLoader;
 import org.springframework.context.expression.BeanFactoryResolver;
+import org.springframework.expression.BeanResolver;
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
 
@@ -151,9 +152,8 @@ public void afterPropertiesSet() {
 		this.argumentResolvers.addResolver(new DataLoaderMethodArgumentResolver());
 		if (springSecurityPresent) {
 			this.argumentResolvers.addResolver(new PrincipalMethodArgumentResolver());
-			AuthenticationPrincipalArgumentResolver authenticationPrincipalResolver = new AuthenticationPrincipalArgumentResolver();
-			authenticationPrincipalResolver.setBeanResolver(new BeanFactoryResolver(obtainApplicationContext()));
-			this.argumentResolvers.addResolver(authenticationPrincipalResolver);
+			BeanResolver beanResolver = new BeanFactoryResolver(obtainApplicationContext());
+			this.argumentResolvers.addResolver(new AuthenticationPrincipalArgumentResolver(beanResolver));
 		}
 		if (KotlinDetector.isKotlinPresent()) {
 			this.argumentResolvers.addResolver(new ContinuationHandlerMethodArgumentResolver());

spring-graphql/src/main/java/org/springframework/graphql/data/method/annotation/support/AuthenticationPrincipalArgumentResolver.java

@@ -31,6 +31,7 @@
 import org.springframework.security.core.context.ReactiveSecurityContextHolder;
 import org.springframework.security.core.context.SecurityContext;
 import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.util.Assert;
 import org.springframework.util.ClassUtils;
 import org.springframework.util.StringUtils;
 import reactor.core.publisher.Mono;
@@ -52,13 +53,14 @@ public class AuthenticationPrincipalArgumentResolver implements HandlerMethodArg
 
 	private ExpressionParser parser = new SpelExpressionParser();
 
-	private BeanResolver beanResolver;
+	private final BeanResolver beanResolver;
 
 	/**
-	 * Sets the {@link BeanResolver} to be used on the expressions
-	 * @param beanResolver the {@link BeanResolver} to use
+	 * Creates a new instance.
+	 * @param beanResolver the {@link BeanResolver} used for resolving beans in SpEL expressions. Cannot be null.
 	 */
-	public void setBeanResolver(BeanResolver beanResolver) {
+	public AuthenticationPrincipalArgumentResolver(BeanResolver beanResolver) {
+		Assert.notNull(beanResolver, "BeanResolver is required");
 		this.beanResolver = beanResolver;
 	}
 

spring-graphql/src/test/java/org/springframework/graphql/data/method/annotation/support/AuthenticationPrincipalArgumentResolverTests.java

@@ -137,7 +137,6 @@ void resolveArgumentWhenAuthenticationPrincipalUsername() throws Exception {
 
 	@Test
 	void resolveArgumentWhenBeanName() throws Exception {
-		this.resolver.setBeanResolver((context, beanName) -> new PrincipalConverter());
 		MethodParameter methodParameter = firstMethodParameter(UserController.class, "beanName", USER_DETAILS_CLASS);
 		Mono<UserDetails> userDetails = (Mono<UserDetails>) this.resolver.resolveArgument(methodParameter, null);
 		assertThat(userDetails.contextWrite(authenticationContext()).block().getUsername()).isEqualTo("user");
@@ -207,7 +206,6 @@ void resolveArgumentWhenMonoAuthenticationPrincipalUsername() throws Exception {
 
 	@Test
 	void resolveArgumentWhenMonoBeanName() throws Exception {
-		this.resolver.setBeanResolver((context, beanName) -> new PrincipalConverter());
 		MethodParameter methodParameter = firstMethodParameter(UserController.class, "beanName", MONO_USER_DETAILS_CLASS);
 		Mono<Mono<UserDetails>> userDetails = (Mono<Mono<UserDetails>>) this.resolver.resolveArgument(methodParameter, null);
 		assertThat(userDetails.flatMap(u -> u).contextWrite(authenticationContext()).block().getUsername()).isEqualTo("user");