SignIn

The `SignIn` payload is a "Pseudo transaction type": an off ledger transaction specific to Xaman, which can be used to identify a user and obtain a token to push sign requests to the end user.

Note that the SignIn transaction type is already embedded in the Xaman SDK and OAuth flows. You only need the SignIn transaction type if you are manually building your own integrations (e.g. API integrations:Backend (SDK / API))

The SignIn transaction type is Xaman specific, signature only, can never be submitted. When sending a JSON transaction payload, you can use all XRPL transaction types, including a Xumm-specific "pseudo transaction type": SignIn.

The payload for a SignIn transaction can look like this:

{
  "txjson": {
    "TransactionType": "SignIn"
  }
}

After the user signs your SignIn request, the server-to-server call (to your configured Webhook location) will receive the signed transaction containing the signed transaction HEX blob.

You can verify the signature using the verify-xrpl-signature package: https://github.com/XRPL-Labs/verify-xrpl-signature

Note: The SignIn transaction type is particularly useful when you want to authenticate a user without performing any transaction on the XRPL.