download rendered overlays via http

[mslacken]

Adds a simple http server on the warewulf port which is rooted at
the $OVERLAYIDR/wwwroot/. Files with the .ww suffix are rendered as
templates where the node can be set via the ?node=$NODE parameter.

[mslacken]

depends on #786 in order to compile

[anderbubble]

Is there any security on this? Similar to the secure: true function, I would want to see a way to prevent regular users from accessing arbitrary overlays and, perhaps, to prevent nodes from seeing each other's overlays.

[mslacken]

Is there any security on this? Similar to the secure: true function, I would want to see a way to prevent regular users from accessing arbitrary overlays and, perhaps, to prevent nodes from seeing each other's overlays.

For the actual implementation only files which are under $WWOVERLYADIR/wwwroot are delivered. Also the secure port is honored.

[griznog]

Curious what does this add we didn't already have by just pulling overlays from the warewulfd port directly?

[mslacken]

Curious what does this add we didn't already have by just pulling overlays from the warewulfd port directly?

At the moment we are pulling a cpio archive of all files in the overlay. This will allow us to pull a single file from an overlay which than can be used as configuration file for e.g. cloud-init.

[griznog]

I think I'd like an option to serve static files through warewulfd but every time I think about what I'd do with it all I can come up with are bad ideas that I don't think I should do. Could the class of use cases like cloud-init be better solved by moving all cloud-init (or whatever) files into a dedicated overlay so the smaller and more focused overlay could be pulled as a complete entity as proposed in #987