Alert When Reloader Triggers a Restart#

Reloader can send a webhook notification whenever it triggers a rolling restart. This is useful for audit trails, operational visibility, and integrating with incident management workflows.

Alerts are sent to a configured webhook endpoint with details about what changed and which workload was restarted.

Supported sinks#

Sink	Value
Raw webhook (default)	`webhook`
Slack	`slack`
Microsoft Teams	`teams`
Google Chat	`gchat`

Configuration#

Alerting is configured through environment variables on the Reloader deployment. The recommended way to set these is through the reloader.deployment.env.secret section of the Helm values, so that the webhook URL is stored as a Kubernetes Secret rather than in plain text.

reloader:
  deployment:
    env:
      secret:
        ALERT_ON_RELOAD: "true"
        ALERT_SINK: "slack"
        ALERT_WEBHOOK_URL: "https://hooks.slack.com/services/..."
        ALERT_ADDITIONAL_INFO: "Cluster: production-eu"

Variable	Required	Description
`ALERT_ON_RELOAD`	Yes	Set to `"true"` to enable alerting. Default: `false`
`ALERT_SINK`	No	Sink type: `slack`, `teams`, `gchat`, or `webhook`. Default: `webhook`
`ALERT_WEBHOOK_URL`	Yes (when alerting enabled)	The webhook URL to send notifications to
`ALERT_ADDITIONAL_INFO`	No	Free-text string appended to the alert payload. Useful for adding context such as cluster name or environment

Examples#

Slack#

Create a Slack Incoming Webhook by following the Slack documentation, then configure:

reloader:
  deployment:
    env:
      secret:
        ALERT_ON_RELOAD: "true"
        ALERT_SINK: "slack"
        ALERT_WEBHOOK_URL: "https://hooks.slack.com/services/<workspace-id>/<channel-id>/<token>"
        ALERT_ADDITIONAL_INFO: "Cluster: production"

Microsoft Teams#

reloader:
  deployment:
    env:
      secret:
        ALERT_ON_RELOAD: "true"
        ALERT_SINK: "teams"
        ALERT_WEBHOOK_URL: "https://outlook.office.com/webhook/..."

Google Chat#

reloader:
  deployment:
    env:
      secret:
        ALERT_ON_RELOAD: "true"
        ALERT_SINK: "gchat"
        ALERT_WEBHOOK_URL: "https://chat.googleapis.com/v1/spaces/..."

Raw webhook#

When ALERT_SINK is set to webhook (or left unset), Reloader sends a plain JSON POST to the URL.

reloader:
  deployment:
    env:
      secret:
        ALERT_ON_RELOAD: "true"
        ALERT_SINK: "webhook"
        ALERT_WEBHOOK_URL: "https://your-internal-service/reloader-events"
        ALERT_ADDITIONAL_INFO: "env=staging"

Using an existing Kubernetes Secret#

If you already manage secrets externally (for example via External Secrets Operator), you can reference an existing Kubernetes Secret instead:

reloader:
  deployment:
    env:
      existing:
        my-alert-secret:
          ALERT_ON_RELOAD: alert_on_reload
          ALERT_SINK: alert_sink
          ALERT_WEBHOOK_URL: alert_webhook_url
          ALERT_ADDITIONAL_INFO: alert_additional_info

This maps each environment variable to a key in the existing Secret named my-alert-secret.