使用登录过滤器时缺少JSF页面样式 [英] JSF page style missing when using login filter

问题描述

我正在使用以下过滤器，以GlassFish作为应用程序服务器来控制对JSF 2.0中所有页面的访问.问题是，使用此代码，尽管过滤器可以正常工作，并且如果用户尝试直接访问其他任何页面，但用户会重定向到log.xhtml，但是login.xhtml看起来并不好(没有显示彩色图像，并且页面形状发生了更改)是.但是，如果我删除sendRedirect语句并将其替换为chain.doFilter语句，则该页面将以相同的方式显示，因为它看起来应该不错，但过滤效果并不明显.我该如何解决这个问题?

I am using following filter to control access to all pages in JSF 2.0 using GlassFish as application server. The problem is that with this code although filter works fine and user are redirected to log.xhtml if they try to acess anyother page directly but the login.xhtml does not look good (no colored image displayed and while page shape changed) as it should be. However if i remove the sendRedirect statement and replace it with chain.doFilter statement, then the page displays in the same way as it should be looking nice and good however filtering does not work obviously. How can I fix this problem?

LoggingFilter.java

public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws ServletException, IOException {   
    HttpServletRequest req = (HttpServletRequest) request;
    LoginBean auth = (LoginBean) req.getSession().getAttribute("loginBean");




    if ((auth != null && auth.isLoggedIn()) || req.getRequestURI().endsWith("/login.xhtml")) {
        // User is logged in, so just continue request.
        HttpServletResponse httpResponse = (HttpServletResponse)response;
        httpResponse.setHeader("Cache-Control", "no-cache, no-store, must-revalidate"); // HTTP 1.1.
        httpResponse.setHeader("Pragma", "no-cache"); // HTTP 1.0.
        httpResponse.setDateHeader("Expires", 0); // Proxies.
        chain.doFilter(request, response);
    } else {
        // User is not logged in, so redirect to index.
        HttpServletResponse res = (HttpServletResponse) response;
        res.sendRedirect(req.getContextPath() + "/faces/login.xhtml");
        //FacesContext.getCurrentInstance().getExternalContext().dispatch("/login.xhtml");
        //chain.doFilter(request, response);
    }
}

推荐答案

此过滤器还将CSS/JS/图像文件上的所有请求重定向到登录页面.浏览器最终得到的响应包含一些表示登录页面的HTML代码，而不是其请求的具体CSS/JS/图像内容，因此浏览器无法应用必要的外观.

This filter also redirects all requests on CSS/JS/image files to the login page. The browser end up getting a response containing some HTML code representing the login page instead of the concrete CSS/JS/image content it requested for and hence the browser fails applying the necessary look'n'feel.

假设您100％使用JSF资源管理(<h:outputStylesheet>等)，因此它们都被/javax.faces.resource/* URI覆盖，请按如下所示重写过滤器:

Provided that you're 100% utilizing JSF resource management (<h:outputStylesheet>, etc) and thus they are all covered by /javax.faces.resource/* URIs, rewrite your filter as follows:

@Override
public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws ServletException, IOException {    
    HttpServletRequest request = (HttpServletRequest) req;
    HttpServletResponse response = (HttpServletResponse) res;
    HttpSession session = request.getSession(false);

    LoginBean auth = (session != null) ? session.getAttribute("loginBean") : null;
    String loginURL = request.getContextPath() + "/faces/login.xhtml";

    boolean loggedIn = auth != null && auth.isLoggedIn();
    boolean loginRequest = request.getRequestURI().equals(loginURL);
    boolean resourceRequest = request.getRequestURI().startsWith(request.getContextPath() + "/faces" + ResourceHandler.RESOURCE_IDENTIFIER);

    if (loggedIn || loginRequest || resourceRequest)) {
        if (!resourceRequest) {
            response.setHeader("Cache-Control", "no-cache, no-store, must-revalidate"); // HTTP 1.1.
            response.setHeader("Pragma", "no-cache"); // HTTP 1.0.
            response.setDateHeader("Expires", 0); // Proxies.
        }

        chain.doFilter(request, response);
    } else {
        response.sendRedirect(loginURL);
    }
}

请注意，不应在资源请求上设置无缓存标头，否则您将失去CSS/JS/图像文件的浏览器缓存优势.

Note that no-cache headers should not be set on resource requests, otherwise you defeat the benefit of the browser cache on CSS/JS/image files.

这篇关于使用登录过滤器时缺少JSF页面样式的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！