edit-webapp contents

[Cantor, Scott]

> A specific example would be whether a copy of web.xml can live there and
> get merged or squished in, or whether it's considered a protected part of the
> distribution and not something that deployers are intended to customize.

web.xml isn't merged.

web.xml is overlaid, and we have a standing commitment that if at all possible, everything that has to be in web.xml to operate any 3.0.0 feature was there in 3.0.0 and will continue working until 4.0.0. As an example, there's a filter in there that is not needed in 3.2.0+ but is now stubbed so that it keeps working. As a further example, SPNEGO wasn't in 3.0.0 but is in 3.2.0 and you have to add that if you want it, if you've copied web.xml.

If we have to make an exception to this policy in a minor release and people would have to edit web.xml by hand if they made changes to it, that would be in the release notes, but not much short of a major security issue could convince me we should do that.

It's virtually impossible to run a complex deployment and not edit web.xml at some point and we have to work around that. There are overlay mechanisms now, but they're recent and I at least don't know them well enough to be relying on them. That's probably a 4.0 thing.

Containers have also had their own overlay features for a while.

Examining the changes in web.xml when doing upgrades is one of the more critical tasks, even if the changes are by design meant to be optional.

-- Scott