# Loki, monolithic: one binary, filesystem storage on a CephFS PVC, 30-day retention.
# Sized for the pinball machines' logs (a few MB a day), not for a fleet.
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: loki-config
  namespace: monitoring
  labels:
    app: loki
data:
  loki.yaml: |
    auth_enabled: false
    server:
      http_listen_port: 3100
      grpc_listen_port: 9096
    common:
      path_prefix: /var/lib/loki
      replication_factor: 1
      ring:
        kvstore:
          store: inmemory
      storage:
        filesystem:
          chunks_directory: /var/lib/loki/chunks
          rules_directory: /var/lib/loki/rules
    schema_config:
      configs:
        - from: 2024-01-01
          store: tsdb
          object_store: filesystem
          schema: v13
          index:
            prefix: index_
            period: 24h
    limits_config:
      retention_period: 720h              # 30 days
      # the machines backfill their history on first ship: accept old entries
      reject_old_samples: true
      reject_old_samples_max_age: 8760h   # a year
    compactor:
      working_directory: /var/lib/loki/compactor
      retention_enabled: true
      delete_request_store: filesystem
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: loki
  namespace: monitoring
  labels:
    app: loki
spec:
  serviceName: loki
  replicas: 1
  selector:
    matchLabels:
      app: loki
  template:
    metadata:
      labels:
        app: loki
    spec:
      securityContext:
        fsGroup: 10001
        runAsNonRoot: true
        runAsUser: 10001
        runAsGroup: 10001
      containers:
        - name: loki
          image: grafana/loki:3.4.4
          args: ["-config.file=/etc/loki/loki.yaml"]
          ports:
            - containerPort: 3100
              name: http
          resources:
            requests:
              cpu: 100m
              memory: 256Mi
            limits:
              cpu: "1"
              memory: 1Gi
          readinessProbe:
            httpGet:
              path: /ready
              port: http
            initialDelaySeconds: 15
          volumeMounts:
            - name: config
              mountPath: /etc/loki
            - name: data
              mountPath: /var/lib/loki
      volumes:
        - name: config
          configMap:
            name: loki-config
  volumeClaimTemplates:
    - metadata:
        name: data
      spec:
        accessModes: ["ReadWriteOnce"]
        storageClassName: csi-cephfs
        resources:
          requests:
            storage: 10Gi
---
apiVersion: v1
kind: Service
metadata:
  name: loki
  namespace: monitoring
  labels:
    app: loki
spec:
  selector:
    app: loki
  ports:
    - name: http
      port: 3100
      targetPort: http
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: loki
  namespace: monitoring
  annotations:
    cert-manager.io/cluster-issuer: letsencrypt
spec:
  ingressClassName: traefik-public
  rules:
    - host: loki.k8s-home.lqx.net
      http:
        paths:
          - backend:
              service:
                name: loki
                port:
                  number: 3100
            path: /
            pathType: Prefix
  tls:
    - hosts:
        - loki.k8s-home.lqx.net
      secretName: loki-tls
---
# picked up by the kube-prom Grafana's datasource sidecar
apiVersion: v1
kind: ConfigMap
metadata:
  name: grafana-loki-datasource
  namespace: monitoring
  labels:
    grafana_datasource: "1"
data:
  loki-datasource.yaml: |
    apiVersion: 1
    datasources:
      - name: Loki
        type: loki
        access: proxy
        url: http://loki.monitoring.svc.cluster.local:3100
        isDefault: false