Heartbeat Floating Session

Send a periodic heartbeat to maintain an active floating license session.

Authentication required: Bearer Token in Authorization header.

Parameters

Idempotency-Key

headerstring

Use a unique value to safely retry this request without repeating its effects.

Example<IDEMPOTENCY-KEY>

Request Body (application/json)

productIdrequired

string

licenseKeyrequired

string

sessionIdrequired

string

The floating-session identifier returned by checkout.

timestamprequired

string | integer

The cryptographic nonce (nextNonce) received from the previous checkout or heartbeat response. Despite the field name, current server code requires nonce equality and does not accept arbitrary client timestamps.

signaturerequired

string

HMAC-SHA256 signature generated using the sessionSecret over the payload 'sessionId:nonce'.

Responses

200Heartbeat extended successfully

410Session checked in or expired

Response Body (200)

code

integer

message

string

expiresAt

string

nextNonce

string

The newly rotated cryptographic nonce generated by the server. This must be used for the next subsequent heartbeat or checkin request.

Request Example

curl -X POST "https://api.keymint.dev/key/heartbeat" \
  -H "Authorization: Bearer <YOUR_API_KEY>" \
  -H "Content-Type: application/json" \
  -d '{
  "productId": "string",
  "licenseKey": "XXXXX-XXXXX-XXXXX-XXXXX",
  "sessionId": "abc123sessionid22chars",
  "timestamp": "string",
  "signature": "string"
}'

Response (200 OK)

{
  "code": 0,
  "message": "string",
  "expiresAt": "2026-10-11T05:25:57.464Z",
  "nextNonce": "1700000000000"
}