Working Java REST Client Example to access CAS REST API

Question

I followed this tutorial to enable REST service on my local CAS server.

However there is no Java example

"Java REST Client Example

We need a real, working, example, the previous one is useless. Many people are emailing me that it is not working, and I confirm it does not work."

I was able to find this but that unfortunately did not work for me.

Any pointers/links? Much appreciated.

Answer 1

Got it!

Here is the complete solution on how to enable CAS REST API and be able to connect to it via JAVA REST client to benefit others

• Get CAS source code.
• Review this article
• Add following to pom.xml like suggested by the article in #2

<dependency> <groupId>org.jasig.cas</groupId> <artifactId>cas-server-integration-restlet</artifactId> <version>${cas.version}</version> <type>jar</type> </dependency>

• Make sure to add following to pom.xml to avoid Spring jar collisions. In my case, cas-server-integration-restlet was dependent on spring-web, which used by default older version of Spring. So, I explicitly defined

<dependency> <groupId>org.springframework</groupId> <artifactId>spring-web</artifactId> <version>3.1.1.RELEASE</version> </dependency>

• Compile your cas code. Should get cas.war in your target folder.
• Upload it to your server, change permissions to tomcat and wait for it to get deployed
• In CATALINA/conf find server.xml and uncomment 8443 port configuration so that our sever will allow SSL connections. Also, specify your certs in here.
• Now navigate to exploded cas.war file and drill down to WEB-INF folder to find deployerConfigContext.xml file. Specify what CAS would use to authenticate. In my case, I used LDAP.
• Add following to web.xml per article above

<servlet> <servlet-name>restlet</servlet-name> <servlet-class>com.noelios.restlet.ext.spring.RestletFrameworkServlet</servlet-class> <load-on-startup>1</load-on-startup> </servlet>

<servlet-mapping> <servlet-name>restlet</servlet-name> <url-pattern>/v1/*</url-pattern> </servlet-mapping>

• Restart tomcat for changes to take effect.
• Test that you can log in via standard CAS UI: https://server:8443/cas/login
• Test that REST API was exposed via: https://server:8443/cas/v1/tickets
• Now let's connect to it. I used this sample code. Make sure to give correct links and username/password
• When I tried running the code as is, it complained about "Caused by: javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target". Basically asking you to install certs. If you have the access to the server, just copy it over. If not, I found this code that will take care of the installation for you if you dont have access or just too lazy :)
• Now, if you run the JAVA CAS Client with valid credentials you should see something like

201
https://server_name:8443/cas/v1/tickets/TGT-4-rhVWLapYuOYi4InSEcmfNcABzaLMCPJgGIzlKqU1vb50zxb6pp-server_name
Tgt is : TGT-4-rhVWLapYuOYi4InSEcmfNcABzaLMCPJgGIzlKqU1vb50zxb6pp-server_name.ndev.coic.mil
Service url is : service=https%3A%2F%2Fmyserver.com%2FtestApplication
https://server_name:8443/cas/v1/tickets/TGT-4-rhVWLapYuOYi4InSEcmfNcABzaLMCPJgGIzlKqU1vb50zxb6pp-server_name
Response code is:  200
200
ST-4-BZNVm9h6k3DAvSQe5I3C-server_name

• You can see 200 code and the ticket. If you were to review logs of your cas on the server, you should see messages about successful athentication and ticket generation.
• Change username/password to some dummy data and try to run the code. You will get 400 error message, which means that permission to access was denied.

Success!