composeTransaction.md

Compose transaction

Requests a payment from the users wallet to a set of given outputs. Internally a BIP-0044 account discovery is performed and user is presented with a list of accounts. After account selection user is presented with list of fee selection. After selecting a fee transaction is signed and returned in hexadecimal format. Change output is added automatically, if needed.

ES6

const result = await TrezorConnect.composeTransaction(params);

CommonJS

TrezorConnect.composeTransaction(params).then(function(result) {

});

Params

Optional common params

• outputs — obligatory Array of recipients Objects described below
• coin — obligatory string determines network definition specified in coins.json file. Coin shortcut, name or label can be used.
• push — optional boolean determines if composed transaction will be broadcasted into blockchain.

Outputs objects:

• regular output
  • amount - obligatory string value to send in satohosi
  • address - obligatory string recipient address
• send-max - spends all available inputs from account
  • type - obligatory with send-max value
  • address - obligatory string recipient address
• opreturn - read more
  • type - obligatory with opreturn value
  • dataHex - optional hexadecimal string with arbitrary data

Example

Send 0.002 BTC to "18WL2iZKmpDYWk1oFavJapdLALxwSjcSk2"

TrezorConnect.composeTransaction({
    outputs: [
        { amount: "200000", address: "18WL2iZKmpDYWk1oFavJapdLALxwSjcSk2" }
    ]
    coin: "btc",
    push: true
});

Result

{
    success: true,
    payload: {
        signatures: Array<string>, // signer signatures
        serializedTx: string,        // serialized transaction 
        txid?: string,             // blockchain transaction id
    }
}

Error

{
    success: false,
    payload: {
        error: string // error message
    }
}

Migration from older version

version 4 and below:

var recipients = [{
    amount: 200000,
    address: "18WL2iZKmpDYWk1oFavJapdLALxwSjcSk2"
}];

TrezorConnect.setCurrency("btc");
TrezorConnect.composeAndSignTx(recipients, function(result) {
    result.signatures    // not changed
    result.serialized_tx // renamed to "serializedTx"
    // added "txid" field if "push" is set to true
});

version 5

var recipients = [{
    amount: "200000",
    address: "18WL2iZKmpDYWk1oFavJapdLALxwSjcSk2"
}];
// params are key-value pairs inside Object
TrezorConnect.composeTransaction({ 
    outputs: recipients,
    coin: "btc"
}).then(function(result) {
    ...
})