The Prometheus config reloader image is released along with the
Prometheus Operator image, tagged with the same semver version. In order
to default to the Prometheus Operator version if no Prometheus config
reloader image is specified, the content of `VERSION` needs to be passed
during compile time.
In addition with both the Prometheus Operator and the Prometheus Config
Reloader being aware of their version, we can log it at process startup
time.
- Move prometheus-config-reloader to cmd/
- Refactor Makefile & contrib/kube-prometheus/Makefile
- Only execute a target if its dependencies changed
- Create empty target file for docker builds
- Replace promu with plain static `go build`
With this patch the Prometheus Operator checks if there are any
Kubernetes ConfigMaps inside the Prometheus namespace which fullfill the
`Spec.RuleSelector` requirement. If so, it creates a RuleFile for each
key in the `ConfigMap.Spec.Data` map inside the Prometheus namespace.
Enable bash pipefail flag for all Makefile operations. This arised when
running `make jsonnet`, where `jsonnet` failed, but the rest of the pipe
covered the error.
This patch introduces a new Custom Resource Definition to the
Prometheus Operator - the Rule CRD. It addresses two main
needs:
1. Prometheus (alerting and recording) Rule validation during creation time
via Kubernetes Custom Resource Definition validation.
2. Life-cycle management of Prometheus application Rules alongside the
application itself, inside the applications Kubernetes namespace, not
necessarily the namespace of the scraping Prometheus instance.
A user defines Prometheus alerting and recording Rules via a Kubernetes
Custom Resource Definition. These Custom Resource Definitions can be
fully validated by the Kubernetes API server during creation time via
automatically generated OpenAPI specifications. Instead of the
restriction of a Prometheus instance to only select Rule definitions
inside its own namespace, the Prometheus specification is extended to
also specify namespaces to look for Rule Custom Resource Definitions
outside its own namespace.
---
Dependent technical changes:
- prometheus: Use github.com/jimmidyson/configmap-reload to reload rules
- prometheus: Remove Prometheus Statefulset deletion function. Starting
with K8s >=1.8 this is handled via OwnerReferences.
- prometheus: Do not add rule files checksum to Prometheus configuration
secret
- prometheus: Update StatefulSet only on relevant changes. Instead of
updating the Prometheus StatefulSet on every `sync()` run, only update
it if the input parameters to `makeStatefulSet` change. Enforce this
via a checksum of the parameters which is saved inside the annotations
of the statefulset.
- e2e/prometheus: Check how often resources (Secret, ConfigMap,
Prometheus CRD, Service) are updated to enforce that Prometheus Operator
only updated created resources if necessary.
- contrib/prometheus-config-reloader: Remove logic to retriev K8s
ConfigMaps. These are mounted into the pod right away now.
