在大多数网站上,当用户要提供用户名和密码来登录系统时,会出现一个复选框,例如“保持登录状态”。如果选中此框,它将使您从同一Web浏览器跨所有 session 登录。如何在Java EE中实现相同功能?
我正在将基于FORM的容器管理的身份验证与JSF登录页面一起使用。
<security-constraint>
<display-name>Student</display-name>
<web-resource-collection>
<web-resource-name>CentralFeed</web-resource-name>
<description/>
<url-pattern>/CentralFeed.jsf</url-pattern>
</web-resource-collection>
<auth-constraint>
<description/>
<role-name>STUDENT</role-name>
<role-name>ADMINISTRATOR</role-name>
</auth-constraint>
</security-constraint>
<login-config>
<auth-method>FORM</auth-method>
<realm-name>jdbc-realm-scholar</realm-name>
<form-login-config>
<form-login-page>/index.jsf</form-login-page>
<form-error-page>/LoginError.jsf</form-error-page>
</form-login-config>
</login-config>
<security-role>
<description>Admin who has ultimate power over everything</description>
<role-name>ADMINISTRATOR</role-name>
</security-role>
<security-role>
<description>Participants of the social networking Bridgeye.com</description>
<role-name>STUDENT</role-name>
</security-role>
最佳答案
Java EE 8及更高版本
如果您使用的是Java EE 8或更高版本,请将 @RememberMe
与 HttpAuthenticationMechanism
一起放在自定义 RememberMeIdentityStore
上。
@ApplicationScoped
@AutoApplySession
@RememberMe
public class CustomAuthenticationMechanism implements HttpAuthenticationMechanism {
@Inject
private IdentityStore identityStore;
@Override
public AuthenticationStatus validateRequest(HttpServletRequest request, HttpServletResponse response, HttpMessageContext context) {
Credential credential = context.getAuthParameters().getCredential();
if (credential != null) {
return context.notifyContainerAboutLogin(identityStore.validate(credential));
}
else {
return context.doNothing();
}
}
}
public class CustomIdentityStore implements RememberMeIdentityStore {
@Inject
private UserService userService; // This is your own EJB.
@Inject
private LoginTokenService loginTokenService; // This is your own EJB.
@Override
public CredentialValidationResult validate(RememberMeCredential credential) {
Optional<User> user = userService.findByLoginToken(credential.getToken());
if (user.isPresent()) {
return new CredentialValidationResult(new CallerPrincipal(user.getEmail()));
}
else {
return CredentialValidationResult.INVALID_RESULT;
}
}
@Override
public String generateLoginToken(CallerPrincipal callerPrincipal, Set<String> groups) {
return loginTokenService.generateLoginToken(callerPrincipal.getName());
}
@Override
public void removeLoginToken(String token) {
loginTokenService.removeLoginToken(token);
}
}
您可以在a real world example中找到Java EE Kickoff Application。Java EE 6/7
如果您使用的是Java EE 6或7,则在用户未登录但存在cookie的情况下,向其本地增长一个长期存在的cookie以跟踪唯一的客户端,并使用Servlet 3.0 API提供的编程性登录
HttpServletRequest#login()
。如果您创建另一个数据库表,且其
java.util.UUID
值为PK,而所涉及的用户的ID为FK,则这是最容易实现的。假定以下登录表单:
<form action="login" method="post">
<input type="text" name="username" />
<input type="password" name="password" />
<input type="checkbox" name="remember" value="true" />
<input type="submit" />
</form>
以下是映射到doPost()
上的Servlet
的/login
方法中的以下内容:String username = request.getParameter("username");
String password = hash(request.getParameter("password"));
boolean remember = "true".equals(request.getParameter("remember"));
User user = userService.find(username, password);
if (user != null) {
request.login(user.getUsername(), user.getPassword()); // Password should already be the hashed variant.
request.getSession().setAttribute("user", user);
if (remember) {
String uuid = UUID.randomUUID().toString();
rememberMeService.save(uuid, user);
addCookie(response, COOKIE_NAME, uuid, COOKIE_AGE);
} else {
rememberMeService.delete(user);
removeCookie(response, COOKIE_NAME);
}
}
(COOKIE_NAME
应该是唯一的cookie名称,例如"remember"
,而COOKIE_AGE
应该是以秒为单位的年龄,例如2592000
为30天)这是映射到受限页面上的
doFilter()
的Filter
方法的样子:HttpServletRequest request = (HttpServletRequest) req;
HttpServletResponse response = (HttpServletResponse) res;
User user = request.getSession().getAttribute("user");
if (user == null) {
String uuid = getCookieValue(request, COOKIE_NAME);
if (uuid != null) {
user = rememberMeService.find(uuid);
if (user != null) {
request.login(user.getUsername(), user.getPassword());
request.getSession().setAttribute("user", user); // Login.
addCookie(response, COOKIE_NAME, uuid, COOKIE_AGE); // Extends age.
} else {
removeCookie(response, COOKIE_NAME);
}
}
}
if (user == null) {
response.sendRedirect("login");
} else {
chain.doFilter(req, res);
}
与那些cookie帮助程序方法结合使用(很遗憾,它们在Servlet API中丢失):public static String getCookieValue(HttpServletRequest request, String name) {
Cookie[] cookies = request.getCookies();
if (cookies != null) {
for (Cookie cookie : cookies) {
if (name.equals(cookie.getName())) {
return cookie.getValue();
}
}
}
return null;
}
public static void addCookie(HttpServletResponse response, String name, String value, int maxAge) {
Cookie cookie = new Cookie(name, value);
cookie.setPath("/");
cookie.setMaxAge(maxAge);
response.addCookie(cookie);
}
public static void removeCookie(HttpServletResponse response, String name) {
addCookie(response, name, null, 0);
}
尽管UUID
非常难以暴力破解,但是您可以为用户提供一个选项,以将“记住”选项锁定到用户的IP地址(request.getRemoteAddr()
),并将其存储/比较在数据库中。这使它更坚固。同样,将“到期日期”存储在数据库中将很有用。无论用户何时更改密码,都应替换
UUID
值也是一个好习惯。Java EE 5或更低版本
请升级。
关于jakarta-ee - 用户登录Web应用程序时如何实现 “Stay Logged In”,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/5082846/