prometheus/oss/alertmanagerconfig.yaml

---
apiVersion: monitoring.coreos.com/v1alpha1
kind: AlertmanagerConfig
metadata:
  name: slack-config
  labels:
    alertmanagerConfig: slack
spec:
  route:
    receiver: 'slack-notifications'
    groupBy: [alertname, job, app]

  receivers:
  - name: 'slack-notifications'
    slackConfigs:
    - apiURL:
        name: alertmanager-slack-webhook
        key: webhookURL
      sendResolved: true
      title: |
        [{{ .Status | toUpper -}}
        {{ if eq .Status "firing" }}:{{ .Alerts.Firing | len }}{{- end -}}
        ] {{ .CommonLabels.alertname }}
      text: |
        {{- if eq .CommonLabels.severity "critical" -}}
        *Severity:* `Critical` :red_circle:
        {{- else if eq .CommonLabels.severity "warning" -}}
        *Severity:* `Warning` :warning:
        {{- else if eq .CommonLabels.severity "info" -}}
        *Severity:* `Info` :information_source:
        {{- else -}}
        *Severity:* `Unknown` :interrobang: {{ .CommonLabels.severity }}
        {{- end }}
        {{- if (index .Alerts 0).Annotations.summary }}
        {{- "\n" -}}
        *Summary:* {{ (index .Alerts 0).Annotations.summary }}
        {{- end }}
        {{- if (index .Alerts 0).Labels.namespace }}
        {{- "\n" -}}
        *Namespace:* `{{ (index .Alerts 0).Labels.namespace }}`
        {{- end }}
        {{ range .Alerts }}
            {{- if .Annotations.description }}
            {{- "\n" -}}
            {{ .Annotations.description }}
            {{- "\n" -}}
            {{- end }}
            {{- if .Annotations.message }}
            {{- "\n" -}}
            {{ .Annotations.message }}
            {{- "\n" -}}
            {{- end }}
        {{- end }}
      color: '{{ if eq .Status "firing" -}}{{ if eq .CommonLabels.severity "warning" -}}warning{{- else if eq .CommonLabels.severity "critical" -}}danger{{- else -}}#439FE0{{- end -}}{{ else -}}good{{- end }}'