com.tapas.evidence.fe.controller.CaptchaController.java Source code

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Here is the source code for com.tapas.evidence.fe.controller.CaptchaController.java

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/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you 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 com.tapas.evidence.fe.controller;

import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;

import javax.imageio.ImageIO;
import javax.inject.Inject;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

import com.octo.captcha.service.CaptchaServiceException;
import com.octo.captcha.service.multitype.MultiTypeCaptchaService;

/**
 * @author Michal Bocek
 * @since 1.0.0
 */
@Controller
public class CaptchaController {
    public static final String CAPTCHA_IMAGE_FORMAT = "jpeg";

    @Inject
    private MultiTypeCaptchaService captchaService;

    @RequestMapping("/captcha.jpg")
    public void showForm(HttpServletRequest request, HttpServletResponse response) throws Exception {
        byte[] captchaChallengeAsJpeg = null;
        // the output stream to render the captcha image as jpeg into
        ByteArrayOutputStream jpegOutputStream = new ByteArrayOutputStream();
        try {
            // get the session id that will identify the generated captcha.
            // the same id must be used to validate the response, the session id is a good candidate!

            String captchaId = request.getSession().getId();
            BufferedImage challenge = captchaService.getImageChallengeForID(captchaId, request.getLocale());

            ImageIO.write(challenge, CAPTCHA_IMAGE_FORMAT, jpegOutputStream);
        } catch (IllegalArgumentException e) {
            response.sendError(HttpServletResponse.SC_NOT_FOUND);
            return;
        } catch (CaptchaServiceException e) {
            response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
            return;
        }

        captchaChallengeAsJpeg = jpegOutputStream.toByteArray();

        // flush it in the response
        response.setHeader("Cache-Control", "no-store");
        response.setHeader("Pragma", "no-cache");
        response.setDateHeader("Expires", 0);
        response.setContentType("image/" + CAPTCHA_IMAGE_FORMAT);

        ServletOutputStream responseOutputStream = response.getOutputStream();
        responseOutputStream.write(captchaChallengeAsJpeg);
        responseOutputStream.flush();
        responseOutputStream.close();
    }
}