This adds a per-target cache of scraped metadata. The metadata is only
available for the lifecycle of the attached target. An API endpoint allows
to select metadata by metric name and a label selection of targets.
Signed-off-by: Fabian Reinartz <freinartz@google.com>
This commit avoids passing the full scrape configuration down to the
scrape loop to fix data races when the scrape configuration is being
reloaded.
Signed-off-by: Simon Pasquier <spasquie@redhat.com>