example: add an example using the BIP329 crate with bdk_wallet

wallet/Cargo.toml

@@ -46,6 +46,7 @@ bdk_wallet = { path = ".", features = ["rusqlite", "file_store", "test-utils"] }
 bdk_file_store = { version = "0.18.1" }
 anyhow = "1"
 rand = "^0.8"
+bip329 = "0.4.0"
 
 [package.metadata.docs.rs]
 all-features = true
@@ -60,3 +61,8 @@ required-features = ["all-keys"]
 name = "miniscriptc"
 path = "examples/compiler.rs"
 required-features = ["compiler"]
+
+[[example]]
+name = "bip329_example"
+path = "examples/bip329_example.rs"
+required-features = ["keys-bip39"]

wallet/examples/bip329_example.rs

@@ -0,0 +1,237 @@
+//! Example demonstrating how to use bdk_wallet with an external BIP-329 library
+//! for managing wallet labels persisted in a separate file.
+
+extern crate anyhow;
+extern crate bdk_wallet;
+extern crate bip329;
+extern crate bitcoin;
+extern crate tempfile;
+
+use anyhow::{anyhow, Context, Result};
+use bdk_wallet::{
+    descriptor,
+    keys::bip39::{Language, Mnemonic, WordCount},
+    keys::GeneratableKey,
+    keys::{DerivableKey, DescriptorSecretKey, ExtendedKey, GeneratedKey},
+    miniscript::{self, Descriptor, DescriptorPublicKey},
+    AddressInfo, KeychainKind, Wallet,
+};
+use bip329::{AddressRecord, Label, LabelRef, Labels, TransactionRecord};
+use bitcoin::{address::NetworkUnchecked, bip32::DerivationPath, Address, Network, OutPoint, Txid};
+use std::{
+    collections::{BTreeMap, HashMap, HashSet},
+    io::ErrorKind,
+    ops::DerefMut,
+    str::FromStr,
+};
+use tempfile::tempdir;
+
+// --- Helper Functions ---
+fn format_ref_str(item_ref: &LabelRef) -> String {
+    match item_ref {
+        LabelRef::Txid(txid) => format!("txid:{}", txid),
+        LabelRef::Address(_) => format!("addr:{}", item_ref),
+        LabelRef::Output(op) => format!("output:{}", op),
+        LabelRef::Input(op) => format!("input:{}", op),
+        LabelRef::PublicKey(pk_str) => format!("pubkey:{}", pk_str),
+        LabelRef::Xpub(xpub_str) => format!("xpub:{}", xpub_str),
+    }
+}
+fn format_bdk_addr_ref(addr: &Address) -> String {
+    format!("addr:{}", addr)
+}
+fn format_bdk_txid_ref(txid: Txid) -> String {
+    format!("txid:{}", txid)
+}
+fn format_bdk_outpoint_ref(op: OutPoint) -> String {
+    format!("output:{}", op)
+}
+
+// --- Main Example Logic ---
+#[allow(clippy::print_stdout, clippy::print_stderr)]
+fn main() -> Result<()> {
+    println!("--- BDK Wallet + BIP-329 Label Example ---");
+
+    let temp_dir = tempdir().context("Failed to create temporary directory")?;
+    let label_file_path = temp_dir.path().join("bdk_bip329_example_labels.jsonl");
+    println!("Using temporary label file: {}", label_file_path.display());
+
+    let network = Network::Regtest;
+
+    // 1. Generate Keys and Descriptors Programmatically
+    println!("Generating keys and descriptors...");
+    let mnemonic: GeneratedKey<_, miniscript::Segwitv0> =
+        Mnemonic::generate((WordCount::Words12, Language::English))
+            .map_err(|_| anyhow!("Mnemonic generation failed"))?;
+    let mnemonic_words = mnemonic.to_string();
+    println!("Generated Mnemonic: {}", mnemonic_words);
+    let mnemonic = Mnemonic::parse_in(Language::English, mnemonic_words)?;
+    let xkey: ExtendedKey = mnemonic.into_extended_key()?;
+    let master_xprv = xkey
+        .into_xprv(network)
+        .ok_or_else(|| anyhow!("Could not derive xprv for network {}", network))?;
+    let external_path = DerivationPath::from_str("m/84h/1h/0h/0")?;
+    let internal_path = DerivationPath::from_str("m/84h/1h/0h/1")?;
+
+    let (external_descriptor, _ext_keymap, _ext_networks): (
+        Descriptor<DescriptorPublicKey>,
+        BTreeMap<DescriptorPublicKey, DescriptorSecretKey>,
+        HashSet<Network>,
+    ) = descriptor!(wpkh((master_xprv, external_path)))?;
+
+    let (internal_descriptor, _int_keymap, _int_networks): (
+        Descriptor<DescriptorPublicKey>,
+        BTreeMap<DescriptorPublicKey, DescriptorSecretKey>,
+        HashSet<Network>,
+    ) = descriptor!(wpkh((master_xprv, internal_path)))?;
+
+    let external_descriptor_str = external_descriptor.to_string();
+    let internal_descriptor_str = internal_descriptor.to_string();
+
+    println!("External Descriptor: {}", external_descriptor_str);
+    println!("Internal Descriptor: {}", internal_descriptor_str);
+
+    // 2. Create the BDK Wallet
+    let wallet = Wallet::create(external_descriptor_str, internal_descriptor_str)
+        .network(network)
+        .create_wallet_no_persist()
+        .context("Failed to create wallet using generated descriptors")?;
+    println!("Wallet created successfully.");
+
+    // Get example items using peek_address
+    let address0: AddressInfo = wallet.peek_address(KeychainKind::External, 0);
+    let address1: AddressInfo = wallet.peek_address(KeychainKind::External, 1);
+
+    let dummy_txid =
+        Txid::from_str("f4184fc596403b9d638783cf57adfe4c75c605f6356fbc91338530e9831e9e16")?;
+    let dummy_outpoint = OutPoint::new(dummy_txid, 0);
+    println!(
+        "Wallet Addresses: Index {} -> {}",
+        address0.index, address0.address
+    );
+    println!("Index {} -> {}", address1.index, address1.address);
+    println!("Dummy TXID: {}", dummy_txid);
+    println!("Dummy OutPoint: {}", dummy_outpoint);
+
+    // 3. Load Labels from temporary file (or create empty)
+    println!("\n--- Loading Labels ---");
+    let mut labels = match Labels::try_from_file(&label_file_path) {
+        Ok(loaded_labels) => {
+            println!(
+                "Loaded {} labels from temporary file '{}'.",
+                loaded_labels.len(),
+                label_file_path.display()
+            );
+            loaded_labels
+        }
+        Err(bip329::error::ParseError::FileReadError(io_err))
+            if io_err.kind() == ErrorKind::NotFound =>
+        {
+            println!(
+                "Temporary label file '{}' not found, starting empty.",
+                label_file_path.display()
+            );
+            Labels::default()
+        }
+        Err(e) => {
+            return Err(anyhow!(
+                "Failed to load labels from {}: {}",
+                label_file_path.display(),
+                e
+            ));
+        }
+    };
+
+    // Build lookup map
+    let mut label_lookup: HashMap<String, String> = HashMap::new();
+    for label_entry in labels.iter() {
+        if let Some(label_text) = label_entry.label() {
+            let ref_str = format_ref_str(&label_entry.ref_());
+            label_lookup.insert(ref_str, label_text.to_string());
+        }
+    }
+
+    // 4. Correlate Wallet Data with Labels
+    println!("\n--- Current Labels for Wallet Items ---");
+    let items_to_lookup: Vec<(&str, String)> = vec![
+        ("Address 0", format_bdk_addr_ref(&address0.address)),
+        ("Address 1", format_bdk_addr_ref(&address1.address)),
+        ("Dummy Tx", format_bdk_txid_ref(dummy_txid)),
+        ("Dummy UTXO", format_bdk_outpoint_ref(dummy_outpoint)),
+    ];
+    for (item_desc, item_ref_str) in &items_to_lookup {
+        match label_lookup.get(item_ref_str) {
+            Some(label_text) => println!("{} ({}): {}", item_desc, item_ref_str, label_text),
+            None => println!("{} ({}): [No Label]", item_desc, item_ref_str),
+        }
+    }
+
+    // 5. Add/Update Labels in Memory
+    println!("\n--- Adding/Updating Labels ---");
+    let addr0_ref_str = format_bdk_addr_ref(&address0.address);
+    let new_addr0_label = "Primary Receiving Address (Index 0)";
+    let labels_vec = labels.deref_mut();
+    match labels_vec
+        .iter_mut()
+        .find(|l| format_ref_str(&l.ref_()) == addr0_ref_str)
+    {
+        Some(label_entry) => {
+            println!("Updating label for {}", addr0_ref_str);
+            match label_entry {
+                Label::Address(record) => record.label = Some(new_addr0_label.to_string()),
+                _ => eprintln!(
+                    "Warning: Found ref string {} but not Address label?",
+                    addr0_ref_str
+                ),
+            }
+        }
+        None => {
+            println!("Adding new label for {}", addr0_ref_str);
+            let addr_unchecked: Address<NetworkUnchecked> =
+                Address::from_str(&address0.address.to_string())?.into_unchecked();
+            labels_vec.push(Label::Address(AddressRecord {
+                ref_: addr_unchecked,
+                label: Some(new_addr0_label.to_string()),
+            }));
+        }
+    }
+    let tx_ref_str = format_bdk_txid_ref(dummy_txid);
+    if !labels_vec
+        .iter()
+        .any(|l| format_ref_str(&l.ref_()) == tx_ref_str)
+    {
+        println!("Adding new label for {}", tx_ref_str);
+        labels_vec.push(Label::Transaction(TransactionRecord {
+            ref_: dummy_txid,
+            label: Some("Simulated Incoming TX".to_string()),
+            origin: None,
+        }));
+    }
+
+    // 6. Export and Save Labels to temporary file
+    println!("\n--- Exporting and Saving Labels ---");
+    match labels.export_to_file(&label_file_path) {
+        Ok(_) => println!(
+            "Labels successfully saved to temporary file '{}'",
+            label_file_path.display()
+        ),
+        Err(e) => eprintln!("Error saving labels: {}", e),
+    }
+
+    // 7. Demonstrate reading the temporary file back
+    println!("\n--- Reading Labels Back from Temporary File ---");
+    match Labels::try_from_file(&label_file_path) {
+        Ok(reloaded_labels) => {
+            println!("Successfully reloaded {} labels:", reloaded_labels.len());
+            for label_entry in reloaded_labels.iter() {
+                if let Some(label_text) = label_entry.label() {
+                    println!("{} -> {}", format_ref_str(&label_entry.ref_()), label_text);
+                }
+            }
+        }
+        Err(e) => eprintln!("Error reloading labels: {}", e),
+    }
+
+    println!("\n--- Example Finished ---");
+    Ok(())
+}