Add RedirectServerAuthenticationFailureHandler

Fixes gh-4816

web/src/main/java/org/springframework/security/web/server/authentication/RedirectServerAuthenticationFailureHandler.java

@@ -0,0 +1,63 @@
+/*
+ * Copyright 2002-2017 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.server.authentication;
+
+import org.springframework.security.core.AuthenticationException;
+import org.springframework.security.web.server.DefaultServerRedirectStrategy;
+import org.springframework.security.web.server.ServerAuthenticationEntryPoint;
+import org.springframework.security.web.server.ServerRedirectStrategy;
+import org.springframework.security.web.server.WebFilterExchange;
+import org.springframework.security.web.server.savedrequest.ServerRequestCache;
+import org.springframework.security.web.server.savedrequest.WebSessionServerRequestCache;
+import org.springframework.util.Assert;
+import org.springframework.web.server.ServerWebExchange;
+import reactor.core.publisher.Mono;
+
+import java.net.URI;
+
+/**
+ * Performs a redirect to a specified location.
+ *
+ * @author Rob Winch
+ * @since 5.0
+ */
+public class RedirectServerAuthenticationFailureHandler
+	implements ServerAuthenticationFailureHandler {
+	private final URI location;
+
+	private ServerRedirectStrategy serverRedirectStrategy = new DefaultServerRedirectStrategy();
+
+	public RedirectServerAuthenticationFailureHandler(String location) {
+		Assert.notNull(location, "location cannot be null");
+		this.location = URI.create(location);
+	}
+
+	/**
+	 * Sets the RedirectStrategy to use.
+	 * @param serverRedirectStrategy the strategy to use. Default is DefaultRedirectStrategy.
+	 */
+	public void setServerRedirectStrategy(ServerRedirectStrategy serverRedirectStrategy) {
+		Assert.notNull(serverRedirectStrategy, "redirectStrategy cannot be null");
+		this.serverRedirectStrategy = serverRedirectStrategy;
+	}
+
+	@Override
+	public Mono<Void> onAuthenticationFailure(
+		WebFilterExchange webFilterExchange, AuthenticationException exception) {
+		return this.serverRedirectStrategy.sendRedirect(webFilterExchange.getExchange(), this.location);
+	}
+}