The current example-app setup in the kube-prometheus project is able to
discover scraping targets in the default namespace. It is not able to
discover the configured Alertmanager in the monitoring namespace.
This patch adds an alertmanager-discovery rbac role, to permit the
above described action. In addition it does the following cleanups:
- Remove kubeconfig configuration in deploy and teardown script. kubectl
chooses .kube/config whenever KUBECONFIG is not set by default
- Remove namespace specification option via NAMESPACE env var. In most
of the manifests the metadata/namespace was hardcoded anyways, in
addition in the promtheus frontend role binding the service account
namespace is hardcoded to default as well.
- Instead of `kubectl {apply,delete}` individual manifests, the deploy
and teardown shell scripts {apply,delete} on the entire folder.
The `prometheus-frontend` role of the example app kubeprometheus section
is scoped to the default namespace. Thereby the frontend Prometheus
instance is not able to discover anything outside of the default
namespace. We might as well restrict the front end service monitor to
the default namespace too.
