Implement create_psbt for Wallet

Cargo.toml

@@ -18,6 +18,8 @@ rustdoc-args = ["--cfg", "docsrs"]
 
 [dependencies]
 bdk_chain = { version = "0.23.1", features = ["miniscript", "serde"], default-features = false }
+bdk_coin_select = { version = "0.4.1" }
+bdk_tx = { version = "0.1.0" }
 bitcoin = { version = "0.32.6", features = ["serde", "base64"], default-features = false }
 miniscript = { version = "12.3.1", features = ["serde"], default-features = false }
 rand_core = { version = "0.6.0" }

examples/psbt.rs

@@ -0,0 +1,117 @@
+#![allow(clippy::print_stdout)]
+
+use std::collections::HashMap;
+use std::str::FromStr;
+
+use bdk_chain::BlockId;
+use bdk_chain::ConfirmationBlockTime;
+use bdk_wallet::psbt::{PsbtParams, SelectionStrategy::*};
+use bdk_wallet::test_utils::*;
+use bdk_wallet::{KeychainKind::External, Wallet};
+use bitcoin::{
+    bip32, consensus,
+    secp256k1::{self, rand},
+    Address, Amount, TxIn, TxOut,
+};
+use rand::Rng;
+
+// This example shows how to create a PSBT using BDK Wallet.
+
+const NETWORK: bitcoin::Network = bitcoin::Network::Signet;
+const SEND_TO: &str = "tb1pw3g5qvnkryghme7pyal228ekj6vq48zc5k983lqtlr2a96n4xw0q5ejknw";
+const AMOUNT: Amount = Amount::from_sat(42_000);
+const FEERATE: f64 = 2.0; // sat/vb
+
+fn main() -> anyhow::Result<()> {
+    let (desc, change_desc) = get_test_wpkh_and_change_desc();
+    let secp = secp256k1::Secp256k1::new();
+
+    // Xpriv to be used for signing the PSBT
+    let xprv = bip32::Xpriv::from_str("tprv8ZgxMBicQKsPdy6LMhUtFHAgpocR8GC6QmwMSFpZs7h6Eziw3SpThFfczTDh5rW2krkqffa11UpX3XkeTTB2FvzZKWXqPY54Y6Rq4AQ5R8L")?;
+
+    // Create wallet and fund it.
+    let mut wallet = Wallet::create(desc, change_desc)
+        .network(NETWORK)
+        .create_wallet_no_persist()?;
+
+    fund_wallet(&mut wallet)?;
+
+    let utxos = wallet
+        .list_unspent()
+        .map(|output| (output.outpoint, output))
+        .collect::<HashMap<_, _>>();
+
+    // Build params.
+    let mut params = PsbtParams::default();
+    let addr = Address::from_str(SEND_TO)?.require_network(NETWORK)?;
+    let feerate = feerate_unchecked(FEERATE);
+    params
+        .add_recipients([(addr, AMOUNT)])
+        .feerate(feerate)
+        .coin_selection(SingleRandomDraw);
+
+    // Create PSBT (which also returns the Finalizer).
+    let (mut psbt, finalizer) = wallet.create_psbt(params)?;
+
+    dbg!(&psbt);
+
+    let tx = &psbt.unsigned_tx;
+    for txin in &tx.input {
+        let op = txin.previous_output;
+        let output = utxos.get(&op).unwrap();
+        println!("TxIn: {}", output.txout.value);
+    }
+    for txout in &tx.output {
+        println!("TxOut: {}", txout.value);
+    }
+
+    let _ = psbt.sign(&xprv, &secp);
+    println!("Signed: {}", !psbt.inputs[0].partial_sigs.is_empty());
+    let finalize_res = finalizer.finalize(&mut psbt);
+    println!("Finalized: {}", finalize_res.is_finalized());
+
+    let tx = psbt.extract_tx()?;
+    let feerate = wallet.calculate_fee_rate(&tx)?;
+    println!("Fee rate: {} sat/vb", bdk_wallet::floating_rate!(feerate));
+
+    println!("{}", consensus::encode::serialize_hex(&tx));
+
+    Ok(())
+}
+
+fn fund_wallet(wallet: &mut Wallet) -> anyhow::Result<()> {
+    let anchor = ConfirmationBlockTime {
+        block_id: BlockId {
+            height: 260071,
+            hash: "000000099f67ae6469d1ad0525d756e24d4b02fbf27d65b3f413d5feb367ec48".parse()?,
+        },
+        confirmation_time: 1752184658,
+    };
+    insert_checkpoint(wallet, anchor.block_id);
+
+    let mut rng = rand::thread_rng();
+
+    // Fund wallet with several random utxos
+    for i in 0..21 {
+        let addr = wallet.reveal_next_address(External).address;
+        let value = 10_000 * (i + 1) + (100 * rng.gen_range(0..10));
+        let tx = bitcoin::Transaction {
+            lock_time: bitcoin::absolute::LockTime::ZERO,
+            version: bitcoin::transaction::Version::TWO,
+            input: vec![TxIn::default()],
+            output: vec![TxOut {
+                script_pubkey: addr.script_pubkey(),
+                value: Amount::from_sat(value),
+            }],
+        };
+        insert_tx_anchor(wallet, tx, anchor.block_id);
+    }
+
+    let tip = BlockId {
+        height: 260171,
+        hash: "0000000b9efb77450e753ae9fd7be9f69219511c27b6e95c28f4126f3e1591c3".parse()?,
+    };
+    insert_checkpoint(wallet, tip);
+
+    Ok(())
+}

examples/rbf.rs

@@ -0,0 +1,92 @@
+#![allow(clippy::print_stdout)]
+
+use std::str::FromStr;
+use std::sync::Arc;
+
+use bdk_chain::BlockId;
+use bdk_wallet::test_utils::*;
+use bdk_wallet::Wallet;
+use bitcoin::{bip32, consensus, secp256k1, Address, FeeRate, Transaction};
+
+// This example shows how to create a Replace-By-Fee (RBF) transaction using BDK Wallet.
+
+const NETWORK: bitcoin::Network = bitcoin::Network::Regtest;
+const SEND_TO: &str = "bcrt1q3yfqg2v9d605r45y5ddt5unz5n8v7jl5yk4a4f";
+
+fn main() -> anyhow::Result<()> {
+    let desc = "wpkh(tprv8ZgxMBicQKsPe5tkv8BYJRupCNULhJYDv6qrtVAK9fNVheU6TbscSedVi8KQk8vVZqXMnsGomtVkR4nprbgsxTS5mAQPV4dpPXNvsmYcgZU/84h/1h/0h/0/*)";
+    let change_desc = "wpkh(tprv8ZgxMBicQKsPe5tkv8BYJRupCNULhJYDv6qrtVAK9fNVheU6TbscSedVi8KQk8vVZqXMnsGomtVkR4nprbgsxTS5mAQPV4dpPXNvsmYcgZU/84h/1h/0h/1/*)";
+    let secp = secp256k1::Secp256k1::new();
+
+    // Xpriv to be used for signing the PSBT
+    let xprv = bip32::Xpriv::from_str("tprv8ZgxMBicQKsPe5tkv8BYJRupCNULhJYDv6qrtVAK9fNVheU6TbscSedVi8KQk8vVZqXMnsGomtVkR4nprbgsxTS5mAQPV4dpPXNvsmYcgZU")?;
+
+    // Create wallet and "fund" it.
+    let mut wallet = Wallet::create(desc, change_desc)
+        .network(NETWORK)
+        .create_wallet_no_persist()?;
+
+    // `tx_1` is the unconfirmed wallet tx that we want to replace.
+    let tx_1 = fund_wallet(&mut wallet)?;
+    wallet.apply_unconfirmed_txs([(tx_1.clone(), 1234567000)]);
+
+    // We'll need to fill in the original recipient details.
+    let addr = Address::from_str(SEND_TO)?.require_network(NETWORK)?;
+    let txo = tx_1
+        .output
+        .iter()
+        .find(|txo| txo.script_pubkey == addr.script_pubkey())
+        .expect("failed to find orginal recipient")
+        .clone();
+
+    // Now build fee bump.
+    let (mut psbt, finalizer) = wallet.replace_by_fee_and_recipients(
+        &[Arc::clone(&tx_1)],
+        FeeRate::from_sat_per_vb_unchecked(5),
+        vec![(txo.script_pubkey, txo.value)],
+    )?;
+
+    let _ = psbt.sign(&xprv, &secp);
+    println!("Signed: {}", !psbt.inputs[0].partial_sigs.is_empty());
+    let finalize_res = finalizer.finalize(&mut psbt);
+    println!("Finalized: {}", finalize_res.is_finalized());
+
+    let tx = psbt.extract_tx()?;
+    let feerate = wallet.calculate_fee_rate(&tx)?;
+    println!("Fee rate: {} sat/vb", bdk_wallet::floating_rate!(feerate));
+
+    println!("{}", consensus::encode::serialize_hex(&tx));
+
+    wallet.apply_unconfirmed_txs([(tx.clone(), 1234567001)]);
+
+    let txid_2 = tx.compute_txid();
+
+    assert!(
+        wallet
+            .tx_graph()
+            .direct_conflicts(&tx_1)
+            .any(|(_, txid)| txid == txid_2),
+        "ERROR: RBF tx does not replace `tx_1`",
+    );
+
+    Ok(())
+}
+
+fn fund_wallet(wallet: &mut Wallet) -> anyhow::Result<Arc<Transaction>> {
+    // The parent of `tx`. This is needed to compute the original fee.
+    let tx0: Transaction = consensus::encode::deserialize_hex(
+        "020000000001010000000000000000000000000000000000000000000000000000000000000000ffffffff025100ffffffff0200f2052a010000001600144d34238b9c4c59b9e2781e2426a142a75b8901ab0000000000000000266a24aa21a9ede2f61c3f71d1defd3fa999dfa36953755c690689799962b48bebd836974e8cf90120000000000000000000000000000000000000000000000000000000000000000000000000",
+    )?;
+
+    let anchor_block = BlockId {
+        height: 101,
+        hash: "3bcc1c447c6b3886f43e416b5c21cf5c139dc4829a71dc78609bc8f6235611c5".parse()?,
+    };
+    insert_tx_anchor(wallet, tx0, anchor_block);
+
+    let tx: Transaction = consensus::encode::deserialize_hex(
+        "020000000001014cb96536e94ba3f840cb5c2c965c8f9a306209de63fcd02060219aaf14f1d7b30000000000fdffffff0280de80020000000016001489120429856e9f41d684a35aba7262a4cecf4bf4f312852701000000160014757a57b3009c0e9b2b9aa548434dc295e21aeb05024730440220400c0a767ce42e0ea02b72faabb7f3433e607b475111285e0975bba1e6fd2e13022059453d83cbacb6652ba075f59ca0437036f3f94cae1959c7c5c0f96a8954707a012102c0851c2d2bddc1dd0b05caeac307703ec0c4b96ecad5a85af47f6420e2ef6c661b000000",
+    )?;
+
+    Ok(Arc::new(tx))
+}

src/lib.rs

@@ -45,6 +45,7 @@ pub use bdk_chain::rusqlite;
 pub use bdk_chain::rusqlite_impl;
 pub use descriptor::template;
 pub use descriptor::HdKeyPaths;
+pub use psbt::*;
 pub use signer;
 pub use signer::SignOptions;
 pub use tx_builder::*;

src/psbt/mod.rs

@@ -17,6 +17,10 @@ use bitcoin::FeeRate;
 use bitcoin::Psbt;
 use bitcoin::TxOut;
 
+mod params;
+
+pub use params::*;
+
 // TODO upstream the functions here to `rust-bitcoin`?
 
 /// Trait to add functions to extract utxos and calculate fees.