SpringSecurity默认页面生成

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默认页面生成

springSecurity过滤器html

DefaultLoginPageGeneratingFilter 生成默认的登陆页面前端
DefaultLogoutPageGeneratingFilter 生成默认的注销页面java

DefaultLoginPageGeneratingFilter

public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
    HttpServletRequest request = (HttpServletRequest)req;
    HttpServletResponse response = (HttpServletResponse)res;
    boolean loginError = this.isErrorPage(request);
    boolean logoutSuccess = this.isLogoutSuccess(request);
    if (!this.isLoginUrlRequest(request) && !loginError && !logoutSuccess) {
        chain.doFilter(request, response);
    } else {
        String loginPageHtml = this.generateLoginPageHtml(request, loginError, logoutSuccess);
        response.setContentType("text/html;charset=UTF-8");
        response.setContentLength(loginPageHtml.getBytes(StandardCharsets.UTF_8).length);
        response.getWriter().write(loginPageHtml);
    }
}

private String generateLoginPageHtml(HttpServletRequest request, boolean loginError, boolean logoutSuccess) {
    String errorMsg = "Invalid credentials";
    if (loginError) {
        HttpSession session = request.getSession(false);
        if (session != null) {
            AuthenticationException ex = (AuthenticationException)session.getAttribute("SPRING_SECURITY_LAST_EXCEPTION");
            errorMsg = ex != null ? ex.getMessage() : "Invalid credentials";
        }
    }

    StringBuilder sb = new StringBuilder();
    sb.append("<!DOCTYPE html>\n<html lang=\"en\">\n <head>\n <meta charset=\"utf-8\">\n <meta name=\"viewport\" content=\"width=device-width, initial-scale=1, shrink-to-fit=no\">\n <meta name=\"description\" content=\"\">\n <meta name=\"author\" content=\"\">\n <title>Please sign in</title>\n <link href=\"https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css\" rel=\"stylesheet\" integrity=\"sha384-/Y6pD6FV/Vv2HJnA6t+vslU6fwYXjCFtcEpHbNJ0lyAFsXTsjBbfaDjzALeQsN6M\" crossorigin=\"anonymous\">\n <link href=\"https://getbootstrap.com/docs/4.0/examples/signin/signin.css\" rel=\"stylesheet\" crossorigin=\"anonymous\"/>\n </head>\n <body>\n <div class=\"container\">\n");
    String contextPath = request.getContextPath();
    if (this.formLoginEnabled) {
        sb.append(" <form class=\"form-signin\" method=\"post\" action=\"" + contextPath + this.authenticationUrl + "\">\n <h2 class=\"form-signin-heading\">Please sign in</h2>\n" + createError(loginError, errorMsg) + createLogoutSuccess(logoutSuccess) + " <p>\n <label for=\"username\" class=\"sr-only\">Username</label>\n <input type=\"text\" id=\"username\" name=\"" + this.usernameParameter + "\" class=\"form-control\" placeholder=\"Username\" required autofocus>\n </p>\n <p>\n <label for=\"password\" class=\"sr-only\">Password</label>\n <input type=\"password\" id=\"password\" name=\"" + this.passwordParameter + "\" class=\"form-control\" placeholder=\"Password\" required>\n </p>\n" + this.createRememberMe(this.rememberMeParameter) + this.renderHiddenInputs(request) + " <button class=\"btn btn-lg btn-primary btn-block\" type=\"submit\">Sign in</button>\n </form>\n");
    }

    if (this.openIdEnabled) {
        sb.append(" <form name=\"oidf\" class=\"form-signin\" method=\"post\" action=\"" + contextPath + this.openIDauthenticationUrl + "\">\n <h2 class=\"form-signin-heading\">Login with OpenID Identity</h2>\n" + createError(loginError, errorMsg) + createLogoutSuccess(logoutSuccess) + " <p>\n <label for=\"username\" class=\"sr-only\">Identity</label>\n <input type=\"text\" id=\"username\" name=\"" + this.openIDusernameParameter + "\" class=\"form-control\" placeholder=\"Username\" required autofocus>\n </p>\n" + this.createRememberMe(this.openIDrememberMeParameter) + this.renderHiddenInputs(request) + " <button class=\"btn btn-lg btn-primary btn-block\" type=\"submit\">Sign in</button>\n </form>\n");
    }

    Iterator var7;
    Entry relyingPartyUrlToName;
    String url;
    String partyName;
    if (this.oauth2LoginEnabled) {
        sb.append("<h2 class=\"form-signin-heading\">Login with OAuth 2.0</h2>");
        sb.append(createError(loginError, errorMsg));
        sb.append(createLogoutSuccess(logoutSuccess));
        sb.append("<table class=\"table table-striped\">\n");
        var7 = this.oauth2AuthenticationUrlToClientName.entrySet().iterator();

        while(var7.hasNext()) {
            relyingPartyUrlToName = (Entry)var7.next();
            sb.append(" <tr><td>");
            url = (String)relyingPartyUrlToName.getKey();
            sb.append("<a href=\"").append(contextPath).append(url).append("\">");
            partyName = HtmlUtils.htmlEscape((String)relyingPartyUrlToName.getValue());
            sb.append(partyName);
            sb.append("</a>");
            sb.append("</td></tr>\n");
        }

        sb.append("</table>\n");
    }

    if (this.saml2LoginEnabled) {
        sb.append("<h2 class=\"form-signin-heading\">Login with SAML 2.0</h2>");
        sb.append(createError(loginError, errorMsg));
        sb.append(createLogoutSuccess(logoutSuccess));
        sb.append("<table class=\"table table-striped\">\n");
        var7 = this.saml2AuthenticationUrlToProviderName.entrySet().iterator();

        while(var7.hasNext()) {
            relyingPartyUrlToName = (Entry)var7.next();
            sb.append(" <tr><td>");
            url = (String)relyingPartyUrlToName.getKey();
            sb.append("<a href=\"").append(contextPath).append(url).append("\">");
            partyName = HtmlUtils.htmlEscape((String)relyingPartyUrlToName.getValue());
            sb.append(partyName);
            sb.append("</a>");
            sb.append("</td></tr>\n");
        }

        sb.append("</table>\n");
    }

    sb.append("</div>\n");
    sb.append("</body></html>");
    return sb.toString();
}
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（1）在doFilter方法中首先判断当前请求是否为登陆出错请求，注销成功请求或者登陆请求。若是这三个请求中的任意一个，就会在DefaultLoginPageGeneratingFilter中生成登陆页面并返回，不然请求继续往下走，执行下一个过滤器。spring

若是当前请求为登陆出错请求，注销成功请求或者登陆请求，使用generateLoginPageHtml生成登陆页面，若是有异常信息一同返回给前端
登陆页面生成后经过HttpServletResponse将登陆页面写回到前端，而后调用return方法跳出过滤器链。

DefaultLogoutPageGeneratingFilter

protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain) throws ServletException, IOException {
    if (this.matcher.matches(request)) {
        this.renderLogout(request, response);
    } else {
        filterChain.doFilter(request, response);
    }

}

private void renderLogout(HttpServletRequest request, HttpServletResponse response) throws IOException {
    String page = "<!DOCTYPE html>\n<html lang=\"en\">\n <head>\n <meta charset=\"utf-8\">\n <meta name=\"viewport\" content=\"width=device-width, initial-scale=1, shrink-to-fit=no\">\n <meta name=\"description\" content=\"\">\n <meta name=\"author\" content=\"\">\n <title>Confirm Log Out?</title>\n <link href=\"https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css\" rel=\"stylesheet\" integrity=\"sha384-/Y6pD6FV/Vv2HJnA6t+vslU6fwYXjCFtcEpHbNJ0lyAFsXTsjBbfaDjzALeQsN6M\" crossorigin=\"anonymous\">\n <link href=\"https://getbootstrap.com/docs/4.0/examples/signin/signin.css\" rel=\"stylesheet\" crossorigin=\"anonymous\"/>\n </head>\n <body>\n <div class=\"container\">\n <form class=\"form-signin\" method=\"post\" action=\"" + request.getContextPath() + "/logout\">\n <h2 class=\"form-signin-heading\">Are you sure you want to log out?</h2>\n" + this.renderHiddenInputs(request) + " <button class=\"btn btn-lg btn-primary btn-block\" type=\"submit\">Log Out</button>\n </form>\n </div>\n </body>\n</html>";
    response.setContentType("text/html;charset=UTF-8");
    response.getWriter().write(page);
}
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请求到来以后，先判断是否注销请求/logout，若是是/logout请求，则渲染一个注销请求的页面，不然走下一个过滤器。bootstrap