#yyds干货盘点#SpringSecurity默认页面生成

登山则情满于山，观海则意溢于海。这篇文章主要讲述#yyds干货盘点#SpringSecurity默认页面生成相关的知识，希望能为你提供帮助。
默认页面生成【#yyds干货盘点#SpringSecurity默认页面生成】springSecurity过滤器

DefaultLoginPageGeneratingFilter生成默认的登录页面
DefaultLogoutPageGeneratingFilter 生成默认的注销页面

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://www.songbingjia.com//"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://www.songbingjia.com//"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 rel="nofollow" href=https://www.songbingjia.com//"").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 rel="nofollow" href=https://www.songbingjia.com//"").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();

（1）在doFilter方法中首先判断当前请求是否为登录出错请求，注销成功请求或者登录请求。如果这三个请求中的任意一个，就会在DefaultLoginPageGeneratingFilter中生成登录页面并返回，否则请求继续往下走，执行下一个过滤器。

如果当前请求为登录出错请求，注销成功请求或者登录请求，使用generateLoginPageHtml生成登录页面，如果有异常信息一同返回给前端
登录页面生成后通过HttpServletResponse将登录页面写回到前端，然后调用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://www.songbingjia.com//"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://www.songbingjia.com//"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);

请求到来之后，先判断是否注销请求/logout，如果是/logout请求，则渲染一个注销请求的页面，否则走下一个过滤器。