/* Copyright (c) 2008 Google Inc.
*
* 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 sample.authsub.src;
import com.google.gdata.client.calendar.CalendarService;
import com.google.gdata.client.http.AuthSubUtil;
import com.google.gdata.util.common.util.Base64;
import java.io.IOException;
import java.security.SecureRandom;
import javax.servlet.ServletException;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpSession;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Logging into this application is trivial and just consists of visiting
* this servlet. This servlet will set an authentication cookie for the
* user and redirect to the page to authorize to Google. Typically, the
* user will be authenticated to the server via the login cookie prior to
* accessing this servlet.
*
*
*/
public class LoginServlet extends HttpServlet {
// On successfully acquiring a token, the servlet will redirect the user to
// the following next URL
/*package*/ static final String NEXT_URL = "/main.jsp";
private static final SecureRandom srng = new SecureRandom();
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
// State to indicate if the user parameters have changed.
boolean stateChanged = false;
// Retrieve user specified hosted domain.
boolean useDefaultDomain =
Boolean.parseBoolean(req.getParameter("defaultdomain"));
boolean useSsl =
Boolean.parseBoolean(req.getParameter("secure"));
String userDomain = req.getParameter("domain");
// Save any persistent data to user session
String calendarFeedRootUrl = CalendarService.CALENDAR_ROOT_URL;
if (useSsl && !calendarFeedRootUrl.startsWith("https")) {
calendarFeedRootUrl = calendarFeedRootUrl.replaceFirst("http", "https");
}
HttpSession userSession = req.getSession(true);
String currentRootUrl =
(String) userSession.getAttribute("feedRootUrl");
String currentDomain =
(String) userSession.getAttribute("userDomain");
if ((currentRootUrl != null && !currentRootUrl.equals(calendarFeedRootUrl))
|| (currentDomain != null && !currentDomain.equals(userDomain))) {
stateChanged = true;
}
userSession.putValue("feedRootUrl", calendarFeedRootUrl);
userSession.putValue("userDomain", userDomain);
String authSubToken = null;
String principal =
Utility.getCookieValueWithName(req.getCookies(), Utility.LOGIN_COOKIE_NAME);
if (!stateChanged && (principal != null)) {
authSubToken = TokenManager.retrieveToken(principal);
}
// Form continue URL
StringBuffer continueUrl = req.getRequestURL();
int index = continueUrl.lastIndexOf("/");
continueUrl.delete(index, continueUrl.length());
// If the user doesn't have an AuthSub token yet, redirect the user to
// the Google page to request an AuthSub token. Otherwise redirect to
// the main page
if (authSubToken == null) {
continueUrl.append("/HandleTokenServlet");
// Check whether to use https for authentication
boolean secure = (Utility.getPrivateKey() != null);
String authSubLogin;
if (useDefaultDomain) {
authSubLogin = AuthSubUtil.getRequestUrl(continueUrl.toString(),
calendarFeedRootUrl,
secure,
true /*session*/);
} else {
authSubLogin = AuthSubUtil.getRequestUrl(req.getParameter("domain"),
continueUrl.toString(),
calendarFeedRootUrl,
secure,
true /*session*/);
}
// Set "authentication" cookie. Typically, a user would have an
// login-cookie for the web service which should be associated to the
// AuthSub token retrieved from Google. For this example, a random
// authentication cookie is assigned.
byte[] randomBytes = new byte[12];
srng.nextBytes(randomBytes);
String cookieValue = Base64.encodeWebSafe(randomBytes, false);
resp.addCookie(new Cookie(Utility.LOGIN_COOKIE_NAME, cookieValue));
resp.sendRedirect(authSubLogin);
} else {
continueUrl.append(NEXT_URL);
resp.sendRedirect(continueUrl.toString());
}
}
}