Stratis Transaction Handoff Specification

Decentralized Stratis Transaction Handoff Specification used for dApps to handoff transaction details to compatible wallets.

Usage and Benefits

Allows dApps to output QR codes in a common format that compatible wallets can recognize and use to build and broadcast transactions.

Allows dApps and wallets to follow one common pattern rather than unique and individual integrations.

Example

User quotes a swap transaction on Opdex, inputting the required information necessary for the dApp to quote the result. The dApp will format the given information into the STHS JSON and create a QR code for compatible wallets to scan. Wallets use the data within the QR code to build the actual transaction that can be reviewed, signed and broadcasted.

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Handoff

dApp Compatibility

dApp compatibility relies on the implementation of the following requirements:

• Gather required fields necessary to complete the raw transaction
• Output a QR code matching the STHS schema
• An available callback endpoint for the broadcasting wallet to notify of the submitted transaction hash and sender wallet address

Wallet Compatibility

Wallet compatibility relies on the implementation of the following requirements:

• Ability to scan or paste QR code data to retrieve transaction data
• User or wallet should validate the entire request
• build and broadcast the transaction, sending the transaction hash result to the callback present in the initial request
• POST the transaction hash and sender wallet address to the callback URL if included in the initial request.

  POST https://some.api.com/transactions
  Content-Type: application/json
  {
      "transactionHash": "206c00b258a671813264d6781451436c6ac091460bdd9d07dc950c6a419a687c",
      "walletAddress": "tHYHem7cLKgoLkeb792yn4WayqKzLrjJak"
  }
  

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STHS Schema

STHS QR Schema Example

{
    "sender": "tHYHem7cLKgoLkeb792yn4WayqKzLrjJak",
    "to": "t8XpH1pNYDgCnqk91ZQKLgpUVeJ7XmomLT",
    "amount": "100.00000000",
    "method": "SwapExactSrcForCrs",
    "parameters": [
        {
            "label": "Token In Amount",
            "value": "12#100000000"
        },
        {
            "label": "CRS Out Minimum",
            "value": "7#200000000"
        },
        {
            "label": "Token In",
            "value": "9#tGSk2dVENuqAQ2rNXbui37XHuurFCTqadD"
        },
        {
            "label": "Recipient",
            "value": "9#tHYHem7cLKgoLkeb792yn4WayqKzLrjJak"
        },
        {
            "label": "Deadline",
            "value": "7#201000000"
        },
    ],
    "callback": "https://some.api.com/transactions"
}

STHS Properties

Property	Type	Description
Sender	Address	The address of the wallet to be used for sending the transaction.
To	Address	The address of the smart contract or user that is being called or transferred to.
Amount	string	A decimal value as string with the total amount of CRS to send with the transaction. Formatted to include exactly as many decimal places that the token supports. (e.g. 1 CRS must be formatted exactly as "1.00000000" with 8 decimal places)
Method	string	The name of the smart contract method being called, if transaction is a smart contract transaction.
Callback	string	An endpoint that the wallet can callback to, notifying dApps of a sent transaction and its transaction hash.
Parameters	Parameter[]	A list of parameters, in the correct order of the smart contract methods signature, if a smart contract is being called.

STHS Parameter Properties

Property	Type	Description
Label	string	A user friendly label wallets can use to describe what the parameter represents.
Value	string	The parameters value, formatted for transaction submission following Stratis standards here: https://academy.stratisplatform.com/Architecture%20Reference/SmartContracts/working-with-contracts.html#parameter-serialization