Any server-side scripting language
Content does not meet the exceptions in the Success Criterion for permitted time limits.
This failure relates to:
The Refresh header is not defined in HTTP/1.1 or HTTP/1.0, but it is widely supported by browsers (tested in Firefox 1.0 and IE 6 on Windows).
Server-side scripting languages allow developers to set the non-standard HTTP header "Refresh" with a time-out (in seconds) and a URL to which the browser is redirected after the specified time-out. If the time interval is too short, people who are blind will not have enough time to make their screen readers read the page before the page refreshes unexpectedly and causes the screen reader to begin reading at the top. Sighted users may also be disoriented by the unexpected refresh.
The HTTP header that is set is Refresh: {time in seconds}; url={URI of
new location}. It is also possible to omit the URL and obtain a
periodically refreshing page, which causes the same problem. The HTTP header
that is set is Refresh: {time in seconds}.
The following example is a failure because a timed server-side redirect is implemented in Java Servlets or JavaServer Pages (JSP).
public void doGet (HttpServletRequest request, HttpServletResponse response)
throws IOException, ServletException {
response.setContentType("text/html");
PrintWriter out = response.getWriter();
response.setHeader("Refresh", "10; URL=TargetPage.html");
out.println("<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\"
\"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">");
out.println("<html><head><title>Redirect</title></head><body>");
out.println("<p>This page will redirect you in 10 seconds.</p>");
out.println("</body></html>");
}
The following example is a failure because a timed server-side redirect is implemented in Active Server Pages (ASP) with VBScript.
<% @Language = "VBScript" %> <% option explicit Response.Clear Response.AddHeader "Refresh", "5; URL=TargetPage.htm" %><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"> … <!--HTML code for content that is shown before the redirect is triggered-->
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Hypertext Transfer Protocol -- HTTP/1.0 (IETF Request for Comments 1945) (plain text)
Hypertext Transfer Protocol -- HTTP/1.1 (IETF Request for Comments 2616) (plain text)
An Exploration of Dynamic Documents by Netscape describes the nonstandard Refresh header that was introduced with Netscape Navigator 1.1.
When a Web page is rendered, check to see if it automatically redirects to another page after some period of time without the user taking any action.
If such a redirect is found then this failure condition applies and content fails the Success Criterion.