Prometheus is Apache 2 licensed, and most source files have the
appropriate copyright license header, but some were missing it without
apparent reason. Correct that by adding it.
This commit moves Scraper handling into a separate scrapePool type.
TargetSets only manage TargetProvider lifecycles and sync the
retrieved updates to the scrapePool.
TargetProviders are now expected to send a full initial target set
within 5 seconds. The scrapePools preserve target state across reloads
and only drop targets after the initial set was synced.
It's actually happening in several places (and for flags, we use the
standard Go time.Duration...). This at least reduces all our
home-grown parsing to one place (in model).
nerve's registration format differs from serverset. With this commit
there is now a dedicated treecache file in util,
and two separate files for serverset and nerve.
Reference:
https://github.com/airbnb/nerve
1. static credentials replaced with defaults.DefaultChainCredentials.
This change ensures that credentials are sourced form all possible
providers available with the aws sdk, in the following order:
env variables, shared awsconfig file in user folder, ec2 instance role.
2. Added a few labels: AvailabilityZone, PublicDns, VpcId (if
available), SubnetId (if in Vpc)
The prefixed target provider changed a pointerized target group that was
reused in the wrapped target provider, causing an ever-increasing chain
of source prefixes in target groups from the Consul target provider.
We now make this bug generally impossible by switching the target group
channel from pointer to value type and thus ensuring that target groups
are copied before being passed on to other parts of the system.
I tried to not let the depointerization leak too far outside of the
channel handling (both upstream and downstream) because I tried that
initially and caused some nasty bugs, which I want to minimize.
Fixes https://github.com/prometheus/prometheus/issues/1083
* Support multiple masters with retries against each master as required.
* Scrape masters' metrics.
* Add role meta label for node/service/master to make it easier for relabeling.
