Docs · Alerts

Webhook reference

A webhook channel receives every alert as a JSON POST. Use it to open tickets, page someone, or feed your own dashboards.

The request

Method POST, header Content-Type: application/json.
Sent from Radardue's servers to the HTTPS URL you saved.
Any 2xx response within 30 seconds counts as delivered. Anything else counts as a failure.

Example

{
  "event": "expiry.alert",
  "subject": "[Acme Dental] shop.acme-dental.com expires in 7 days",
  "text": "TLS certificate for shop.acme-dental.com (Acme Dental) expires in 7 days, on Mon 19 Oct 2026.\nIssuer/registrar: Let's Encrypt (R11)\n\nOpen in Radardue: https://radardue.com/app/items/42 …",
  "source": "radardue.com",
  "item": {
    "id": 42,
    "type": "certificate",
    "name": "shop.acme-dental.com",
    "port": 443,
    "client": "Acme Dental",
    "client_id": 7,
    "expires_at": "2026-10-19T09:12:44Z",
    "days_left": 7,
    "issuer": "Let's Encrypt (R11)",
    "url": "https://radardue.com/app/items/42"
  }
}

Fields

Field	Type	Description
`event`	string	`expiry.alert` for real alerts, `test` for the Send test button.
`subject`	string	One-line summary, the same as the email subject.
`text`	string	Plain-text body, the same as the email body.
`source`	string	Always `radardue.com`.
`item.id`	number	Stable ID of the tracked item.
`item.type`	string	`certificate`, `domain` or `renewal`.
`item.name`	string	Hostname, domain, or the renewal's name.
`item.port`	number	Certificates only. The port that was checked.
`item.client`	string	Client name.
`item.client_id`	number	Stable ID of the client.
`item.expires_at`	string	Expiry time in UTC, RFC 3339.
`item.days_left`	number	Whole days until expiry; negative once expired.
`item.issuer`	string	Certificate issuer or domain registrar, when known.
`item.url`	string	Link to the item in Radardue.

Test messages have "event": "test" and no item.

Good to know

One item, several alerts. An item alerts at each step of the schedule and daily in its final week. If you open tickets, use item.id together with item.expires_at as the key so you update one ticket instead of creating new ones.
Securing your endpoint. Requests aren't signed yet. Put a long random token in the URL path or query string and reject requests without it.
Stability. We only ever add fields to this payload. Ignore fields you don't recognise.

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