Logs dashboard

[v-zhuravlev]

This adds conditional pods logs dashboard by using log library, that can be used to generate dashboard in any mixin (Linux, Windows, Clickhouse, MySQL, PostgreSQL etc) with custom chained label selectors.

Features:

• Enable or disable dash with enableLokiLogs
• Use common kube labels as selectors: ['cluster', 'namespace', 'app', 'pod', 'container']
• Use free type regex_search variable to 'grep' lines as last resort
• Enable or disable graph that shows log volume grouped by application label (configurable). Suggested default is app, which is available in default promtail helm chart.
• Smart line output:
  • Append with pod name by default. If pod variable is selected - append with container name instead.
  • Don't show timestamps to preserve space, but store timestamp in additional field to have an option to view it.

[povilasv]

Hey, original mixin is only Grafana dashboard and Prometheus Alerting and recording rules. See https://github.com/kubernetes-monitoring/kubernetes-mixin/blob/master/DESIGN.md#aims

The logging part I would say an open question. And which logging system fits Monitoring Mixins best is also an open question. If we would merge this, this means that we are going into direction Grafana's Loki product.

[v-zhuravlev]

Sure, but this logs additional is still a Grafana dashboard as well, but with different DS. It is opt-in addition, no problem if you don't you use Loki, you just keep it disabled.

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