AppFuse provides a sweet starting point for developing web applications. You choose the frameworks, AppFuse generates the skeleton application.
At its core, the web security of AppFuse 2.0.1 and earlier applications relies on the modular and extensible Acegi authentication framework. In this tutorial, we look at a basic integration of Crowd with Acegi, using an application generated by AppFuse.
If you're working with AppFuse 2.0.2 or later, it uses Spring Security instead of Acegi. Please see our separate tutorial.
This tutorial assumes you have installed Crowd 1.5.1 or later.
Step 1. Get AppFuse
In this tutorial, we will be using the Struts2-basic archetype to create the project, but the other types should be similar. For more information, consult the AppFuse quickstart guide. In particular, it outlines the database requirements for AppFuse.
Create the project.
Since we will be editing the core Acegi configuration, we will need the full source code of the application.
Play with it.
Shut it down.
Step 2. Let Crowd Know about AppFuse
appfuse as an application via the Crowd Console. See Adding an Application for more information.
Step 3. Add the Crowd Acegi Connector to AppFuse
Open up the
pom.xml and add the Crowd client libraries as a project dependency:
You will also need to create the file
In particular, the application name and password must match the values defined for the application added in Step 2.
Finally, copy the
myproject/src/main/resources/crowd-ehcache.xml. This file defines the cache properties, such as cache timeouts, used when accessing data from the Crowd server.
Step 4. Hook Up Centralised Authentication
Before modifying the security configuration, you will need to add the Spring configuration file to wire up the Crowd client beans. Add the
applicationContext-CrowdClient.xml configuration file to the list of
AppFuse neatly stores all the Acegi configuration in
myproject/src/main/webapp/WEB-INF/security.xml. In order to get centralised authentication, we will need to set up Acegi to use the wrapped authenticator class we just created. Edit the Acegi beans in
Add the definition of the CrowdUserDetailsService:
Add the definition of the RemoteCrowdAuthenticationProvider which will delegate Acegi's authentication requests to Crowd:
Replace the DaoAuthenticationProvider with our authenticator in the authentication manager:
Now do a:
- Head over to
You should now be able to authenticate the users in your Crowd repository that meet all of the following conditions:
- They are in a Crowd directory assigned to the AppFuse application in Crowd. See more information.
- They are in Crowd groups named
ADMIN. You will need to add these groups and assign the user as a member of the groups. These Crowd group names map to the Acegi authorisation roles defined in the AppFuse application.
- They are allowed to authenticate with the AppFuse application because EITHER they are in a group allowed to authenticate with Crowd see more OR their container directory allows all users to authenticate see more.
Congratulations. You have centralised authentication
Application-level centralised user management
One quirk you may notice is that you can't view the profile details of users who exist in Crowd, but did not exist in AppFuse prior to the Crowd integration. Although it's possible to authenticate a Crowd user 'dude' and still run AppFuse as 'dude', 'dude' will not be in AppFuse's local database. AppFuse makes use of a database-backed user management system. In order to achieve application-level centralised user management, AppFuse will need to delegate its calls to create, retrieve, update and delete users to Crowd using Crowd's remote API. This will prevent data redundancy and eliminate the hassle of data synchronisation. This is beyond the scope of this short tutorial.
Step 5. Hook Up Single Sign-On
Enabling single sign-on (SSO) requires a little more tweaking of the
Change the default processing filter to Crowd's SSO filter:
Add the definition of the CrowdLogoutHandler:
Update the definition of the LogoutFilter to use the CrowdLogoutHandler. You may need to uncomment the logout filter.
If the logout filter is not defined in the filter invocation list, you will need to add it:
SSO will only work for users that are able to authenticate with both appplications and are authorised to use both applications. Try out the following:
- Log in to Crowd – you should be logged in to AppFuse.
- Log out of AppFuse – you should be logged out of Crowd.
- Log in to AppFuse; log out of Crowd; log in to Crowd as another user; refresh AppFuse – you should be logged in as the new user.
Congratulations, you have SSO