kapplier

A simpler (and faster) alternative to kube-applier.

Watches a directory for YAML files and runs kubectl apply on them — on a fixed interval and/or triggered by a webhook. No GUI, no git, no kubectl binary required.

Intended to be used with a git-sync sidecar (>=v4), which syncs a git repo to disk and calls the webhook after each sync.

Endpoints

Endpoint	Method	Description
/webhook	POST	Trigger an immediate reconcile run
/metrics	GET	Prometheus metrics

Metrics

Metric	Labels	Description
file_apply_count	success, file	Number of times each file has been applied
run_latency_seconds	success, file	Time taken to apply each file
reconcile_duration_seconds	—	Total wall-clock time for the last reconcile run
reconcile_failure_count	—	Number of apply failures in the last reconcile run

Configuration

All options can be set as CLI flags or environment variables.

Usage: kapplier [OPTIONS]

Options:
      --user-agent <USER_AGENT>
          [env: USER_AGENT] [default: kapplier]
      --path <PATH>
          [env: PATH] [default: repo]
      --subpath <SUBPATH>
          [env: SUBPATH] [default: ]
      --ignore-hidden-directories <IGNORE_HIDDEN_DIRECTORIES>
          [env: IGNORE_HIDDEN_DIRECTORIES] [default: true] [possible values: true, false]
      --supported-extensions <SUPPORTED_EXTENSIONS>
          [env: SUPPORTED_EXTENSIONS] [default: yml yaml]
      --full-run-interval-seconds <FULL_RUN_INTERVAL_SECONDS>
          [env: FULL_RUN_INTERVAL_SECONDS] [default: 300]
      --webserver-port <WEBSERVER_PORT>
          [env: WEBSERVER_PORT] [default: 9100]
      --filter-annotation <FILTER_ANNOTATION>
          [env: FILTER_ANNOTATION] Only apply documents with this annotation (e.g. kapplier.io/managed=true or just kapplier.io/managed)
      --filter-label <FILTER_LABEL>
          [env: FILTER_LABEL] Only apply documents with this label (e.g. app=myapp or just app)
  -h, --help
          Print help
  -V, --version
          Print version

Example

See examples/kapplier.yaml for a full Kubernetes deployment with a git-sync sidecar.

The example configures git-sync to sync a repo to /repo and call the webhook after each sync, while kapplier watches /repo/kapplier.git/deploy for YAML files to apply.