How to create an alias for a context name in Tomcat 6/7?

Question

We have a context that includes an underscore and that is unfortunately causing problems w/ a load balancer and cookie paths. Our URLs resemble this:

https://example.com/the_context/login.jsp

Where we have deployed a war file named "the_context.war".

I'd like to somehow alias the context name so both of these urls would effectively be the same:

https://example.com/the_context/login.jsp
https://example.com/thecontext/login.jsp

Ideally this would be done w/o deploying the application twice. Is this possible in Tomcat 6 and/or 7 ?

Answer 1

While it may be possible to create an "alias" my hacking into Tomcat's mapper component (that maps requests to Contexts), you will have problem if your web application calls ServletContext.getContextPath() as that information does not depend on the incoming request.

There are two typical solutions:
a) Name one URL as "the canonical" one and redirect your users from the old URL to the new one. That is to respond with HTTP status code 301 and a redirection.
b) Rewrite URLs in the incoming request and in response (if needed).

a) can be done by a simple Filter or by using a standard "rewrite" one
b) needs some mode advanced rewrite implementation

You may use UrlRewriteFilter (http://wiki.apache.org/tomcat/AddOns#UrlRewrite )(in any version of Tomcat), RewriteValve (in Tomcat 8), mod_rewrite in Apache HTTPD server (if your Tomcat runs behind that server).

Comments

Thanks a lot that make sense.