{{- if and .Values.metrics.enabled .Values.metrics.prometheusRule.enabled (.Capabilities.APIVersions.Has "monitoring.coreos.com/v1/PrometheusRule") }}
apiVersion: monitoring.coreos.com/v1
kind: PrometheusRule
metadata:
  name: {{ include "php-homepage.fullname" . }}
  labels:
    {{- include "php-homepage.labels" . | nindent 4 }}
    {{- with .Values.metrics.prometheusRule.labels }}
    {{- toYaml . | nindent 4 }}
    {{- end }}
  {{- with .Values.metrics.prometheusRule.annotations }}
  annotations:
    {{- toYaml . | nindent 4 }}
  {{- end }}
spec:
  groups:
    - name: {{ include "php-homepage.fullname" . }}.apache
      rules:
        {{- if .Values.metrics.prometheusRule.exporterDown.enabled }}
        - alert: ApacheExporterDown
          expr: up{namespace={{ .Release.Namespace | quote }},service={{ include "php-homepage.fullname" . | quote }},endpoint="metrics"} == 0
          for: {{ .Values.metrics.prometheusRule.exporterDown.for }}
          labels:
            severity: {{ .Values.metrics.prometheusRule.exporterDown.severity | quote }}
          annotations:
            summary: {{ printf "Apache exporter for %s is unavailable" (include "php-homepage.fullname" .) | quote }}
            description: {{ printf "Prometheus has not been able to scrape the Apache exporter in namespace %s." .Release.Namespace | quote }}
        {{- end }}
        {{- if .Values.metrics.prometheusRule.apacheDown.enabled }}
        - alert: ApacheDown
          expr: apache_up{namespace={{ .Release.Namespace | quote }},service={{ include "php-homepage.fullname" . | quote }}} == 0
          for: {{ .Values.metrics.prometheusRule.apacheDown.for }}
          labels:
            severity: {{ .Values.metrics.prometheusRule.apacheDown.severity | quote }}
          annotations:
            summary: {{ printf "Apache for %s is unavailable" (include "php-homepage.fullname" .) | quote }}
            description: {{ printf "The exporter cannot read Apache server-status in namespace %s." .Release.Namespace | quote }}
        {{- end }}
        {{- if .Values.metrics.prometheusRule.workerSaturation.enabled }}
        - alert: ApacheWorkerSaturation
          expr: (sum(apache_workers{namespace={{ .Release.Namespace | quote }},service={{ include "php-homepage.fullname" . | quote }},state="busy"}) / clamp_min(sum(apache_workers{namespace={{ .Release.Namespace | quote }},service={{ include "php-homepage.fullname" . | quote }}}), 1)) > {{ .Values.metrics.prometheusRule.workerSaturation.threshold }}
          for: {{ .Values.metrics.prometheusRule.workerSaturation.for }}
          labels:
            severity: {{ .Values.metrics.prometheusRule.workerSaturation.severity | quote }}
          annotations:
            summary: {{ printf "Apache workers for %s are nearly exhausted" (include "php-homepage.fullname" .) | quote }}
            description: {{ printf "The ratio of busy to available Apache workers has exceeded the configured threshold (%v) for the configured duration." .Values.metrics.prometheusRule.workerSaturation.threshold | quote }}
        {{- end }}
{{- end }}