This use-case can be done for accessing distributed attribute data in a cache grid. Many end-users already use Oracle Coherence and re-using the information from a Coherence Grid with OES would strengthen a distributed SOA environment. These name/value pairs from a Coherence Grid can be used as attributes within Oracle Entitlements Server (OES).
How does this currently work?
OES can use the Oracle Coherence product to access an Oracle Coherence Data Grid. At startup of the OES Security Module, the Coherence product will startup and connect to a configured Coherence cluster containing distributed data. Once Coherence connects, it automatically gets a copy of all the data already within that grid. The data can be retrieved with a custom OES Attribute Retriever for use in Authorization Policy decisions for an application. See the diagram below which shows how this works "Out-of-the-Box" today:
Current Solution for OES/Coherence Attribute Retrievers
This use-case can currently be solved using OES and Coherence. In the description below a WebLogic Portal application was used with OES, a custom attribute retriever and Coherence in a sample domain/test environment.
NOTE:
- Any application can be used for testing and a "WebLogic Portal" application is not necessary. It is used as an example here of what it would look like.
- Setup you WLS Domain:
- Run a client to load the data into the coherence grid. In this case the only cluster member of the Coherence Grid is the Coherence Server started within the container. The idea is that there is *already* an existing Coherence Grid with Distributed Data which one will connect to.
- Start the WLS Domain which has its security enforced by OES with the startWebLogic.cmd/sh file. Within OES an Attribute Retriever is used which gets the requested attribute from the Coherence Grid. See the sample Attribute Retriever Code below.
- Make sure the Attribute Retriever and attribute being used is configured within the Authorization Provider of the WLS container.
- Test your sample application to see if your policy which has the attribute being retrieved will retrieve it from the Coherence Grid. In this example, a Portal application was used and I modified the following resource within the OES Administration Console to check the value of the attribute we are retrieving:
- Access the Portal application URL and login.
- If the Coherence Grid is running, then the value of "OK" should be returned in the Attribute Retriever
- As a test, change the value in the Grid for the "coh_AccessPage" attribute to something other than "OK".
- Logout of the Portal application and log back in. This time you will see a different result and the user not authorized to see the page. If you are having problems with the authorization, please review the previous blog on Troubleshooting authorization decisions.
Add the coherence jar files to the setDomainEnv.bat/sh script and make sure you specify a host for the Coherence Cluster being used as mentioned above:
set COHERENCE_OPTIONS=-Dtangosol.coherence.localhost=169.254.25.129
set JAVA_OPTIONS=%JAVA_OPTIONS% %COHERENCE_OPTIONS%
@REM SET THE CLASSPATH
set COHERENCE_DIR=
set COHERENCE_LIBS=%COHERENCE_DIR%\tangosol.jar;%COHERENCE_DIR%\coherence.jar;%COHERENCE_DIR%\coherence-web.jar
set CLASSPATH=%PRE_CLASSPATH%;%WEBLOGIC_CLASSPATH%;%POST_CLASSPATH%;%WLP_POST_CLASSPATH%;%COHERENCE_LIBS%
NOTE: Coherence is using the default cache-config.xml file which is bundled within the coherence jar files. The implication of this is that Coherence is not tune for performance and if one wants to override this, then a -Dtangosol.coherence.cacheconfig=
Resources: BEAPortalSample/wlp/portalAndALES_WAR/com_bea_p13n/Page/QL_portal_Education_and_Support
Constraint: checkIncominAttrRet(accesspage, execPage) and coh_AccessPage = "OK"
Subjects: USER:beaID:weblogic
OES Custom Attribute Retriever Code
The Coherence added code is in bold:
package com.bea.ales.sample2;
import com.bea.security.providers.authorization.asi.AttributeRetriever;
import weblogic.security.spi.Resource;
import weblogic.security.service.ContextHandler;
import javax.security.auth.Subject;
import java.util.*;
// Modify the build path for this application to include
// the tangosol.jar and coherence.jar files within one's environment.
import com.tangosol.net.CacheFactory;
import com.tangosol.net.NamedCache;
/**
* Implementation for performing attribute retrieval.
* This plugin can get to remote repositories to figure out the value
* of a certain attribute at runtime. Multiple retrievers may be
* registered for the same attribute name, they will be called in
* order until one returns a non-null result.
*/
public class CohAttributeRetriever implements AttributeRetriever {
private static final String cohaccessPage = "coh_AccessPage";
private String[] attributes = {cohaccessPage };
private NamedCache myCache = null;
// “Prime” the Coherence information within the constructor
// of the AttributeRetriever
public CohAttributeRetriever() {
CacheFactory.ensureCluster();
myCache = CacheFactory.getCache("mycache");
}
/**
* Returns the names of attributes handled by this class.
* indicates that the retriever will be considered capable of
* handling any attribute name.
*
* @return the names associated with this object
*/
public String[] getHandledAttributeNames() {
return attributes;
}
/**
* Retrieve the value of the named attribute.
* Additional authorization request data
* is made available to allow for more complex attribute retrieval.
*
* @param name the name of the needed attribute
* @param subject the subject associated with the request
* @param roles the role membership of the subject
* @param resource the resource associated with the request
* @param contextHandle the context associated with the request
* @return the attributes value, or
null if not found*/
public Object getAttributeValue(String name,
Subject subject,
Map roles,
Resource resource,
ContextHandler contextHandle) {
// Set default value
String attrValue = "no";
if (name.equals(cohaccessPage)) {
try {
// The only call to the Coherence Named Cache to get
// whatever attribute is needed from the Coherence Grid
attrValue = (String)myCache.get(cohaccessPage);
System.out.println("--> COH Value is \"" + attrValue + "\"");
} catch (Exception e) {
System.out.println("E:"+e.getLocalizedMessage()+" "+ e);
}
finally {}
return attrValue;
}
// default value returned...
return attrValue;
}
}//end of AttributeRetriever
