Watch-Only Wallets

In LWK, the core functions of a wallet are split between two components for enhanced security: Signers manage private keys, while the Wollet handles everything else.

The term "Wollet" is not a typo; it stands for "Watch-Only wallet." A wollet provides view-only access, allowing you to generate addresses and see your balance without ever handling private keys. This design is crucial for security, as it keeps your private keys isolated.

A LWK wollet can perform the following operations:

• Generate addresses
• List transactions
• Get balance
• Create transactions (but not sign them)

CT descriptors

A Wollet is defined by a CT descriptor, which consists in a Bitcoin descriptor plus the descriptor blinding key.

In the previous section, we saw how to generate a single sig CT descriptor from a signer with Signer::wpkh_slip77_descriptor(), which returns something like:

ct(slip77(...),elwpkh([ffffffff/84h/1h/0h]xpub...))

• ct(...,...)
• slip77(...) the descriptor blinding key
• el the "Elements" prefix
• wpkh([ffffffff/84h/1h/0h]xpub...) the "Bitcoin descriptor", with

The CT descriptors defines the wallet spending conditions. In this case it requires a single signature from a specific signer.

LWK supports more complex spending conditions, such as multisig.

Create a Wollet

From the CT descriptor, you need to generate a WolletDescriptor. Calling WolletDescriptor::from_str() will perform some basic validation of the descriptor, and fails if the descriptor is not supported by LWK.

Once you have a WolletDescriptor you can create a Wollet using either Wollet::without_persist() (keeps wallet data in memory) or Wollet::with_fs_persist() (stores wallet data on filesystem).

LWK also allows Wollets to have a custom persister.

use lwk_wollet::{ElementsNetwork, Wollet, WolletDescriptor};

let desc = signer.wpkh_slip77_descriptor()?;
let wd = WolletDescriptor::from_str(&desc)?;
let network = ElementsNetwork::LiquidTestnet;
let mut wollet = Wollet::without_persist(network, wd)?;

const desc = signer.wpkhSlip77Descriptor();
const wollet = new lwk.Wollet(network, desc);

Generate Addresses

You can generate a wallet confidential address with Wollet::address().

This address can receive any Liquid asset or amount.

let addr = wollet.address(None)?;

const addr = wollet.address(null).address().toString();

Get Transactions and Balance

It's possibile to get the list of wallet transactions with Wollet::transactions() and the balance Wollet::balance().

Note: Liquid transactions are confidential, meaining that only sender and receiver can see their asset and amount. Wollet unblinds the transactions and returns unblinded data that can be shown to the user.

Wollet however does not have internet access. To fetch (new) wallet data, you need to use a "client" that fetches wallet transactions from some server. In the next section we explain how (new) blockchain data can be obtained and added to the wallet.

let txs = wollet.transactions()?;
let balance = wollet.balance()?;

const txs = wollet.transactions();
const balance = wollet.balance();

Next: Update the Wallet