On 01/09/2015 21:40, Edward Burns wrote:
> MT> On 01/09/2015 01:15, Shing Wai Chan wrote:
>
> SWC> If this is a Servlet 4.0 feature, there is most likely a Servlet
> SWC> TCK assertion for this. Mark, can you help us understand why you
> SWC> are taking such a strong position against it as a representative
> SWC> for the hugely important Tomcat community?
>
>>>>>> On Tue, 1 Sep 2015 19:19:45 +0100, Mark Thomas <markt_at_apache.org> said:
>
> MT> As I have said previously on this thread, web applications are meant
> MT> to be independent of the context path at which they are
> MT> deployed. Anything that encourages web application developers to
> MT> think that they can code to a specific context path is a bad idea.
>
> May I paraphrase the spirit of your position as "don't make it any
> easier than absolutely necessary to do bad things."
No, that is not the spirit of my position. That is a secondary concern.
The spirit of my position is a combination of "Web applications should
be independent of the context path at which they are deployed" and
"deployment is not a developer concern".
> While I agree with
> the spirit of your position, in this case I think that spirit is trumped
> by several factors, in decreasing order of importance.
>
> 1. many containers already offer this in a proprietary fashion
Many containers provide an in WAR method to define a preferred context
path that can be overridden during deployment? References please.
> 2. it sure would be convenient to offer it as a standard
Convenient to who? For what use cases?
The testing use case is the best argument made so far and I'm not
convinced by that.
> 3. we can put it at the bottom of a priority list, allowing the
> preservation of out-of-webapp context-root specification
>
> 4. we can name the XML element sufficiently obviously to make it clear
> the priority is below other ways of specifying the context-root.
>
> SWC> Yes, we should allow the container to override the context root
> SWC> configuration. We can discuss more on the XML element name once we
> SWC> agree to have this feature.
>
> MT> Then as I stated above, Tomcat will *always* override whatever is set
> MT> here - effectively ignoring it. I have no wish to deal with the
> MT> inevitable conflicts that will result when multiple applications all
> MT> want to be deployed with a context path of "".
>
> This is a good point. What do you do in Tomcat if multiple apps are
> attempted to be deployed with the same context root, even when it is ""?
It is only possible to do this in Tomcat if the deprecated / strongly
discouraged method of defining web applications in the main
configuration file is used (which is bad because you have to restart
Tomcat to make any changes). I'd need to look at the code to see what
would happen. I think the second and subsequent apps with the same path
will fail to start but it is possible that the entire container will
fail to start.
If using Tomcat's documented deployment approaches it simply isn't
possible for a conflict to occur.
Mark