I have been looking at solutions for sharing session data between mutliple war files. I came across the following solution http://www.fwd.at/tomcat/sharing-session-data-howto.html
The basic idea of it is that if you have more than one war file, you can set a cookie using the sessionid of the first context that is used.
The cookie can be set using a path that will apply to all contexts/applications.
For example, if I have the following configuration for 3 applications
/myapp/app1
/myapp/app2
/myapp/app3
I can set a cookie as follows
/myapp sessionid.
The sessionid cookie will then be sent to any request with /myapp in the address. This allows the session id to then be used by any of the contexts.
The only problem with this approach is that it was written in 2003 and tested on Tomcat 4.
What are your opinions of this approach? Is there a better way of doing it?
Thanks
That article is indeed heavily outdated.
On Tomcat 5.5 and 6.0 you can just set emptySessionPath
attribute to true
in the <Connector>
element in /conf/server.xml
.
<Connector ... emptySessionPath="true">
On Tomcat 7.0 this has changed because this is now configureable from the Servlet 3.0 API on. It's then on Tomcat's side configureable by setting sessionCookiePath
to /
in <Context>
element in any responsible context.xml
file.
<Context ... sessionCookiePath="/">
As said, there's a new Servlet 3.0 API which allows you to configure the session cookie through the standard API. You can do it either declaratively by adding the following to the web.xml
:
<session-config>
<cookie-config>
<path>/</path>
</cookie-config>
</session-config>
or programmatically by SessionCookieConfig
which is available by ServletContext#getSessionCookieConfig()
.
getServletContext().getSessionCookieConfig().setPath("/");
You could do this in ServletContextListener#contextInitialized()
or HttpServlet#init()
.