---
# roles/monitoring_stack/templates/loki-config.yml.j2
# Loki configuration for centralized log aggregation

# === CONCEPT: Loki vs Traditional Logging ===
# Traditional: Index entire log content (expensive, slow)
# Loki: Index only metadata labels (cheap, fast)
# Think of Loki as "Prometheus for logs"

auth_enabled: false

server:
  http_listen_port: {{ loki_port }}
  grpc_listen_port: 9096

common:
  path_prefix: /loki
  storage:
    filesystem:
      chunks_directory: /loki/chunks
      rules_directory: /loki/rules
  replication_factor: 1
  ring:
    instance_addr: 127.0.0.1
    kvstore:
      store: inmemory

schema_config:
  configs:
    - from: 2024-01-01
      store: tsdb
      object_store: filesystem
      schema: v13
      index:
        prefix: index_
        period: 24h

# === RETENTION: Automatic Log Cleanup ===
# Keeps logs for {{ loki_retention }} (default: 7 days)
# Prevents disk from filling up with old logs
limits_config:
  retention_period: {{ loki_retention }}
  reject_old_samples: true
  reject_old_samples_max_age: 168h

# === PRO-TIP: Query Optimization ===
# Limit concurrent queries to prevent overload
query_scheduler:
  max_outstanding_requests_per_tenant: 100

# === LABEL EXTRACTION ===
# Automatically extract structured fields from logs
# Example: {"level":"error"} becomes label level="error"
ruler:
  alertmanager_url: http://localhost:9093