Hi Folks,

I was using the filter: org.keycloak.adapters.saml.servlet.SamlFilter in our application.

I got the following exception in the logs:

ERROR [org.apache.catalina.core.ContainerBase.[jboss.web].[localhost].[/].[AppName]] Servlet.service() for servlet NasDefault threw exception: java.lang.RuntimeException: This method is not supported in a restored authenticated request
    at org.keycloak.adapters.servlet.FilterSessionStore$1.getDateHeader(FilterSessionStore.java:178) [:1.7.0.CR1]
    at org.apache.catalina.servlets.DefaultServlet.checkIfModifiedSince(DefaultServlet.java:1731) [:]
    at org.apache.catalina.servlets.DefaultServlet.checkIfHeaders(DefaultServlet.java:608) [:]
    at org.apache.catalina.servlets.DefaultServlet.serveResource(DefaultServlet.java:714) [:]
    at org.apache.catalina.servlets.DefaultServlet.doGet(DefaultServlet.java:368) [:]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:734) [:1.0.0.Final]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:847) [:1.0.0.Final]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:324) [:]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:242) [:]
... (trimmed)
...
    at org.keycloak.adapters.saml.servlet.SamlFilter.doFilter(SamlFilter.java:125) [:1.7.0.CR1]
...(trimmed)
...
etc.

After looking into the Keycloak code base, I saw the method (implemented in an anonymous class):
javax.servlet.http.HttpServletRequestWrapper#getDateHeader

inside the class: org.keycloak.adapters.servlet.FilterSessionStore

The code was:
@Override
public long getDateHeader(String name) {
    if (!needRequestRestore) return super.getDateHeader(name);
         throw new RuntimeException("This method is not supported in a restored authenticated request");
    }

Looks like a particular case isn't implemented yet, and an exception is thrown.

After looking into the JEE API at: http://docs.oracle.com/javaee/7/api/javax/servlet/http/HttpServletRequest.html#getDateHeader-java.lang.String-

It is required that any class implementing HttpServletRequest getDateHeader() method, return a -1 in case it cannot get the required header.

Hence, I suggest that instead of throwing an exception to handle the error condition, we should return -1.

Any help appreciated.

Thanks,

Regards,

Akshay