/*
* Copyright 2002-2013 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.security.web.method.annotation;
import java.lang.annotation.Annotation;
import org.springframework.core.MethodParameter;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.annotation.AuthenticationPrincipal;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.support.WebDataBinderFactory;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.method.support.HandlerMethodArgumentResolver;
import org.springframework.web.method.support.ModelAndViewContainer;
/**
* Allows resolving the {@link Authentication#getPrincipal()} using the
* {@link AuthenticationPrincipal} annotation. For example, the following
* {@link Controller}:
*
* <pre>
* @Controller
* public class MyController {
* @MessageMapping("/im")
* public void im(@AuthenticationPrincipal CustomUser customUser) {
* // do something with CustomUser
* }
* </pre>
*
* <p>
* Will resolve the CustomUser argument using
* {@link Authentication#getPrincipal()} from the {@link SecurityContextHolder}.
* If the {@link Authentication} or {@link Authentication#getPrincipal()} is
* null, it will return null. If the types do not match, null will be returned
* unless {@link AuthenticationPrincipal#errorOnInvalidType()} is true in which
* case a {@link ClassCastException} will be thrown.
* </p>
*
* <p>
* Alternatively, users can create a custom meta annotation as shown below:
* </p>
*
* <pre>
* @Target({ ElementType.PARAMETER })
* @Retention(RetentionPolicy.RUNTIME)
* @AuthenticationPrincipal
* public @interface CurrentUser {
* }
* </pre>
*
* <p>
* The custom annotation can then be used instead. For example:
* </p>
*
* <pre>
* @Controller
* public class MyController {
* @MessageMapping("/im")
* public void im(@CurrentUser CustomUser customUser) {
* // do something with CustomUser
* }
* </pre>
*
* @author Rob Winch
* @since 4.0
*/
public final class AuthenticationPrincipalArgumentResolver implements
HandlerMethodArgumentResolver {
/* (non-Javadoc)
* @see org.springframework.web.method.support.HandlerMethodArgumentResolver#supportsParameter(org.springframework.core.MethodParameter)
*/
public boolean supportsParameter(MethodParameter parameter) {
return findMethodAnnotation(AuthenticationPrincipal.class, parameter) != null;
}
/* (non-Javadoc)
* @see org.springframework.web.method.support.HandlerMethodArgumentResolver#resolveArgument(org.springframework.core.MethodParameter, org.springframework.web.method.support.ModelAndViewContainer, org.springframework.web.context.request.NativeWebRequest, org.springframework.web.bind.support.WebDataBinderFactory)
*/
public Object resolveArgument(MethodParameter parameter,
ModelAndViewContainer mavContainer, NativeWebRequest webRequest,
WebDataBinderFactory binderFactory) throws Exception {
Authentication authentication = SecurityContextHolder.getContext().getAuthentication();
if(authentication == null) {
return null;
}
Object principal = authentication.getPrincipal();
if(principal != null && !parameter.getParameterType().isAssignableFrom(principal.getClass())) {
AuthenticationPrincipal authPrincipal = findMethodAnnotation(AuthenticationPrincipal.class, parameter);
if(authPrincipal.errorOnInvalidType()) {
throw new ClassCastException(principal + " is not assignable to " + parameter.getParameterType());
} else {
return null;
}
}
return principal;
}
/**
* Obtains the specified {@link Annotation} on the specified {@link MethodParameter}.
*
* @param annotationClass the class of the {@link Annotation} to find on the {@link MethodParameter}
* @param parameter the {@link MethodParameter} to search for an {@link Annotation}
* @return the {@link Annotation} that was found or null.
*/
private <T extends Annotation> T findMethodAnnotation(Class<T> annotationClass, MethodParameter parameter) {
T annotation = parameter.getParameterAnnotation(annotationClass);
if(annotation != null) {
return annotation;
}
Annotation[] annotationsToSearch = parameter.getParameterAnnotations();
for(Annotation toSearch : annotationsToSearch) {
annotation = AnnotationUtils.findAnnotation(toSearch.annotationType(), annotationClass);
if(annotation != null) {
return annotation;
}
}
return null;
}
}