7c80aec454
This allows specifying different "policy paths" for the internal and external descriptors, and adds additional checks to make sure they are compatibile (i.e. the timelocks are expressed in the same unit). It's still suboptimal, since the `n_sequence`s are per-input and not per-transaction, so it should be possibile to spend different inputs with different, otherwise incompatible, `CSV` timelocks, but that requires a larger refactor that can be done in a future patch. This commit also tries to clarify how the "policy path" should be used by adding a fairly detailed example to the docs.
BDK
A modern, lightweight, descriptor-based wallet library written in Rust!
Project Homepage | Documentation
About
The bdk library aims to be the core building block for Bitcoin wallets of any kind.
- It uses Miniscript to support descriptors with generalized conditions. This exact same library can be used to build single-sig wallets, multisigs, timelocked contracts and more.
- It supports multiple blockchain backends and databases, allowing developers to choose exactly what's right for their projects.
- It's built to be cross-platform: the core logic works on desktop, mobile, and even WebAssembly.
- It's very easy to extend: developers can implement customized logic for blockchain backends, databases, signers, coin selection, and more, without having to fork and modify this library.
Examples
Sync the balance of a descriptor
use bdk::Wallet;
use bdk::database::MemoryDatabase;
use bdk::blockchain::{noop_progress, ElectrumBlockchain};
use bdk::electrum_client::Client;
fn main() -> Result<(), bdk::Error> {
let client = Client::new("ssl://electrum.blockstream.info:60002", None)?;
let wallet = Wallet::new(
"wpkh([c258d2e4/84h/1h/0h]tpubDDYkZojQFQjht8Tm4jsS3iuEmKjTiEGjG6KnuFNKKJb5A6ZUCUZKdvLdSDWofKi4ToRCwb9poe1XdqfUnP4jaJjCB2Zwv11ZLgSbnZSNecE/0/*)",
Some("wpkh([c258d2e4/84h/1h/0h]tpubDDYkZojQFQjht8Tm4jsS3iuEmKjTiEGjG6KnuFNKKJb5A6ZUCUZKdvLdSDWofKi4ToRCwb9poe1XdqfUnP4jaJjCB2Zwv11ZLgSbnZSNecE/1/*)"),
bitcoin::Network::Testnet,
MemoryDatabase::default(),
ElectrumBlockchain::from(client)
)?;
wallet.sync(noop_progress(), None)?;
println!("Descriptor balance: {} SAT", wallet.get_balance()?);
Ok(())
}
Generate a few addresses
use bdk::{Wallet, OfflineWallet};
use bdk::database::MemoryDatabase;
fn main() -> Result<(), bdk::Error> {
let wallet: OfflineWallet<_> = Wallet::new_offline(
"wpkh([c258d2e4/84h/1h/0h]tpubDDYkZojQFQjht8Tm4jsS3iuEmKjTiEGjG6KnuFNKKJb5A6ZUCUZKdvLdSDWofKi4ToRCwb9poe1XdqfUnP4jaJjCB2Zwv11ZLgSbnZSNecE/0/*)",
Some("wpkh([c258d2e4/84h/1h/0h]tpubDDYkZojQFQjht8Tm4jsS3iuEmKjTiEGjG6KnuFNKKJb5A6ZUCUZKdvLdSDWofKi4ToRCwb9poe1XdqfUnP4jaJjCB2Zwv11ZLgSbnZSNecE/1/*)"),
bitcoin::Network::Testnet,
MemoryDatabase::default(),
)?;
println!("Address #0: {}", wallet.get_new_address()?);
println!("Address #1: {}", wallet.get_new_address()?);
println!("Address #2: {}", wallet.get_new_address()?);
Ok(())
}
Create a transaction
use bdk::{FeeRate, TxBuilder, Wallet};
use bdk::database::MemoryDatabase;
use bdk::blockchain::{noop_progress, ElectrumBlockchain};
use bdk::electrum_client::Client;
use bitcoin::consensus::serialize;
fn main() -> Result<(), bdk::Error> {
let client = Client::new("ssl://electrum.blockstream.info:60002", None)?;
let wallet = Wallet::new(
"wpkh([c258d2e4/84h/1h/0h]tpubDDYkZojQFQjht8Tm4jsS3iuEmKjTiEGjG6KnuFNKKJb5A6ZUCUZKdvLdSDWofKi4ToRCwb9poe1XdqfUnP4jaJjCB2Zwv11ZLgSbnZSNecE/0/*)",
Some("wpkh([c258d2e4/84h/1h/0h]tpubDDYkZojQFQjht8Tm4jsS3iuEmKjTiEGjG6KnuFNKKJb5A6ZUCUZKdvLdSDWofKi4ToRCwb9poe1XdqfUnP4jaJjCB2Zwv11ZLgSbnZSNecE/1/*)"),
bitcoin::Network::Testnet,
MemoryDatabase::default(),
ElectrumBlockchain::from(client)
)?;
wallet.sync(noop_progress(), None)?;
let send_to = wallet.get_new_address()?;
let (psbt, details) = wallet.create_tx(
TxBuilder::with_recipients(vec![(send_to.script_pubkey(), 50_000)])
.enable_rbf()
.do_not_spend_change()
.fee_rate(FeeRate::from_sat_per_vb(5.0))
)?;
println!("Transaction details: {:#?}", details);
println!("Unsigned PSBT: {}", base64::encode(&serialize(&psbt)));
Ok(())
}
Sign a transaction
use bdk::{Wallet, OfflineWallet};
use bdk::database::MemoryDatabase;
use bitcoin::consensus::deserialize;
fn main() -> Result<(), bdk::Error> {
let wallet: OfflineWallet<_> = Wallet::new_offline(
"wpkh([c258d2e4/84h/1h/0h]tprv8griRPhA7342zfRyB6CqeKF8CJDXYu5pgnj1cjL1u2ngKcJha5jjTRimG82ABzJQ4MQe71CV54xfn25BbhCNfEGGJZnxvCDQCd6JkbvxW6h/0/*)",
Some("wpkh([c258d2e4/84h/1h/0h]tprv8griRPhA7342zfRyB6CqeKF8CJDXYu5pgnj1cjL1u2ngKcJha5jjTRimG82ABzJQ4MQe71CV54xfn25BbhCNfEGGJZnxvCDQCd6JkbvxW6h/1/*)"),
bitcoin::Network::Testnet,
MemoryDatabase::default(),
)?;
let psbt = "...";
let psbt = deserialize(&base64::decode(psbt).unwrap())?;
let (signed_psbt, finalized) = wallet.sign(psbt, None)?;
Ok(())
}