Checkout

The checkout() method allows your site to request a transaction from the user. This will open a popup for the user to select the address to send from — or cancel the request. During the payment process, the signed transaction is sent (relayed) to the network but also returned to the caller, e.g. for processing in your site, storage on your server or re-submittal.

Table of Contents

1. Request
2. Options
3. Result

Request

Result: -

const options = {
  appName: 'Hub API Docs',
  recipient: 'NQ07 0000 0000 0000 0000 0000 0000 0000 0000',
  value: 3.14 * 1e5, /* 3.14 NIM */
  // See more options in the table below
};

// All client requests are async and return a promise
const signedTransaction = await hubApi.checkout(options);

Options

(On mobile, scroll right to see the whole table.)

Option	Type	Required?	Description
appName	string	yes	The name of your app, should be as short as possible.
recipient	string	yes	The human-readable address of the recipient (your shop/app).
value	number	yes	Value of the transaction, in Luna.
shopLogoUrl	string	no	An image URL. Must be on the same origin as the request is sent from. Should be square and at least 146x146 px.
fee	number	no	Transaction fee in luna. Default: 0
extraData	string or Uint8Array	no	Extra data that should be sent with the transaction.
sender	string	no	Human-readable address of the sender. If the address exists in the user’s Hub and has enough balance, the address selection is skipped.
forceSender	boolean	no	Whether to force the submitted sender address. If this option is true, an exception is thrown when either the sender address does not exist or does not have sufficient balance. When false (default), the user will be shown the address selector instead. (Only relevant in connection with the sender option.)
validityDuration	number	no	The duration (in number of blocks) that the signed transaction should be valid for. The maximum and default is 120.
flags	number	no	A Nimiq.Transaction.Flag, only required if the transaction should create a contract.
recipientType	number	no	The Nimiq.AccountType of the recipient. Only required if the transaction should create a contract.

Result

The checkout() method returns a promise which resolves to a SignedTransaction:

interface SignedTransaction {
    serializedTx: string;                  // HEX signed and serialized transaction
    hash: string;                          // HEX transaction hash

    raw: {
        signerPublicKey: Uint8Array;       // Serialized public key of the signer
        signature: Uint8Array;             // Serialized signature of the signer

        sender: string;                    // Human-readable address of sender
        senderType: Nimiq.AccountType;    // 0, 1, 2, 3 - see recipientType above

        recipient: string;                 // Human-readable address of recipient
        recipientType: Nimiq.AccountType; // 0, 1, 2, 3 - see above

        value: number;
        fee: number;
        validityStartHeight: number;       // Automatically determined validity
                                           // start height of the transaction
        extraData: Uint8Array;
        flags: number;
        networkId: number;
    }
}

The serializedTx can be handed to a Nimiq JSON-RPC’s sendRawTransaction method.

The raw object can be handed to the NanoApi’s relayTransaction method.