CAS getting attributes to Oracle APEX on tomcat

Question

I configured my Oracle Application Express to have a authentication schema based on HTTP Header Variable.

To be more specific, it is based on remote_user, which is set to domain login, thanks to connection with CAS.

Right now i need to get attributes. I know the method in Java how to do it:

AttributePrincipal principal = (AttributePrincipal) request.getUserPrincipal();
final Map attributes = principal.getAttributes();

The question are there other possibilities to receive this attributes w/o using java, (code that i can use in Oracle Application Express) e.g. JavaScript...

Or maybe there is a method how to use Java code in APEX? I use APEX-ORDS-TOMCAT system and there is something like:

.../webapps/${app_name}/WEB-INF/classes and .../webapps/${app_name}/WEB-INF/lib

Maybe this is the place i can place some java .class and use it in some way in Oracle APEX?

Great thx for any help

Paweł Żurkiewicz Paweł Żurkiewicz · Accepted Answer · 2019-11-15T12:57:45

I created the solution by myself.

Create a Java Servlet that handles Attributes from CAS and return a JSON object (doGet):

AttributePrincipal principal = (AttributePrincipal) request.getUserPrincipal();
final Map attributes = principal.getAttributes();

JSONObject jsonObj = new JSONObject(attributes);

PrintWriter out = response.getWriter();

response.setContentType("application/json");
response.setCharacterEncoding("UTF-8");

out.print(jsonObj);

Compile .java to .class and put it folder:

${TOMCAT_BASE}/webapps/${APP_NAME}/WEB-INF/classes/${PACKAGE_NAME}

Put CAS, JSON, Servlet libraries to

${TOMCAT_BASE}/webapps/${APP_NAME}/WEB-INF/lib

List of the libs (verions can be different):

json-20190722.jar
javax.servlet-api-4.0.1.jar
cas-client-core-3.6.1.jar
cas-client-support-saml-3.4.1.jar
commons-logging-1.1.1.jar
joda-time-2.10.4.jar
log4j-1.2.17.jar
slf4j-api-1.7.28.jar
slf4j-simple-1.7.25.jar

Configure web.xml to use this servlet

    <servlet>
        <servlet-name>SERVLET_NAME</servlet-name>
        <servlet-class>${PACKAGE_NAME}.{CLASS_NAME}</servlet-class>
    </servlet>

    <servlet-mapping>
        <servlet-name>SERVLET_NAME</servlet-name>
        <url-pattern>/{PATH}</url-pattern>
    </servlet-mapping>

and now on the servlet is available on {host}:{port}/{APP_NAME}/{PATH}

We can reach it from the APEX with JavaScript e.g. a function to send json to item.value

function loadJSON(itemName) {
  var xhttp = new XMLHttpRequest();
  xhttp.onreadystatechange = function() {
    if (this.readyState == 4 && this.status == 200) {
      document.getElementById(itemName).value = this.responseText
    }
  };
  xhttp.open("GET", "{PATH}", true);
  xhttp.send();
}
loadJSON("P1_USER_INFO");

CAS getting attributes to Oracle APEX on tomcat

1 Answers