Prior to this commit, packaging a Spring Boot application as a container
image with Cloud Native Buildpacks could result in unwanted browser
caching behavior, with "Last-Modified" HTTP response headers pointing to
dates in the far past.
This is due to CNB resetting the last-modified date metadata for static
files (for build reproducibility and container layer caching) and Spring
static resource handling relying on that information when serving static
resources.
This commit introduces a new configuration property
`spring.web.resources.cache.use-last-modified` that can be used to
disable this behavior in Spring if the application is meant to run as a
container image built by CNB.
The default value for this property remains `true` since this remains
the default value in Spring Framework and using that information in
other deployment models is a perfectly valid use case.
Fixes gh-24099
When a Configuration is copied, any before and after resolve actions
that are registered with its ResolvableDependencies are also copied
over. This means that, when a copied configuration is resolved the
resolution actions may be called on a ResolvableDependencies instances
that isn't the one to which they were added.
Previously, the above-described Gradle behaviour would result in
BootJar accessed the ResolvedConfiguration of a Configuration that may
not have yet been resolved. At best this would trigger Configuration
resolution and at worst it would fail. A failure could occur if the
configuration had been copied so that it could be made resolvable.
The afterResolve action would then try to access the
ResolvedConfiguration of the original Configuration. This would trigger
a resolution attempt that fails due to the original configuration being
marked as unresolvable.
This commit updates the afterResolve action in BootJar to check that
the ResolvableDependencies with which it is called matches the
ResolvableDependencies with which it was original registered. Only
when the two match, and therefore the configuration has actually been
resolved, does processing proceed.
Fixes gh-24072
Andy Wilkinson
Stephane Nicoll
Brian Clozel