AjaxAuthenticationSuccessHandler.java

/*
 * Copyright (c) 2020-2025 Estonian Information System Authority
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package eu.webeid.example.security.ajax;

import com.fasterxml.jackson.annotation.JsonProperty;
import tools.jackson.core.JsonProcessingException;
import tools.jackson.databind.ObjectMapper;
import tools.jackson.databind.ObjectWriter;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.security.core.Authentication;
import org.springframework.security.web.authentication.SimpleUrlAuthenticationSuccessHandler;
import org.springframework.stereotype.Component;

import java.io.IOException;

/**
 * Write custom response on having user successfully authenticated.
 * <p>
 * This is not required in production application, but to demonstrate that
 * authentication and authorization steps have been passed.
 */
@Component
public class AjaxAuthenticationSuccessHandler extends SimpleUrlAuthenticationSuccessHandler {
    private static final Logger LOG = LoggerFactory.getLogger(AjaxAuthenticationSuccessHandler.class);

    @Override
    public void onAuthenticationSuccess(
            HttpServletRequest request,
            HttpServletResponse response,
            Authentication authentication
    )
            throws IOException {
        LOG.info("onAuthenticationSuccess(): {}", authentication);

        response.setStatus(HttpServletResponse.SC_OK);
        response.setHeader("Content-Type", "application/json; charset=utf-8");

        response.getWriter().write(AuthSuccessDTO.asJson(authentication));
    }

    public static class AuthSuccessDTO {
        private static final ObjectWriter OBJECT_WRITER = new ObjectMapper().writerFor(AuthSuccessDTO.class);

        @JsonProperty("sub")
        private String sub;

        @JsonProperty("auth")
        private String auth;

        public static String asJson(Authentication authentication) throws JsonProcessingException {
            final AuthSuccessDTO dto = new AuthSuccessDTO();
            dto.sub = authentication.getName();
            dto.auth = authentication.getAuthorities().toString();
            return OBJECT_WRITER.writeValueAsString(dto);
        }
    }
}