Extracted the Esplora wallet into a struct

side-node/src/bitcoin/clients/esplora.rs

@@ -1,7 +1,10 @@
 use std::{collections::BTreeSet, fs, io::Write, str::FromStr};
 
 use bdk::keys::bip39::Mnemonic;
-use bdk_esplora::{esplora_client, EsploraAsyncExt};
+use bdk_esplora::{
+    esplora_client::{self, AsyncClient},
+    EsploraAsyncExt,
+};
 use bdk_wallet::{
     bitcoin::{Address, Amount, Network, Script},
     chain::ConfirmationTimeHeightAnchor,
@@ -17,31 +20,35 @@ use crate::utils;
 const STOP_GAP: usize = 50;
 const PARALLEL_REQUESTS: usize = 5;
 
+pub struct EsploraWallet {
+    wallet: Wallet,
+    db: Store<KeychainKind, ConfirmationTimeHeightAnchor>,
+    client: AsyncClient,
+}
+
+impl EsploraWallet {
     pub(crate) fn build_send_tx(
-    mut wallet: Wallet,
+        &mut self,
         faucet_address: Address,
         amount: Amount,
     ) -> Result<bitcoin::Transaction, anyhow::Error> {
-    let mut tx_builder = wallet.build_tx();
+        let mut tx_builder = self.wallet.build_tx();
         tx_builder
             .add_recipient(faucet_address.script_pubkey(), amount)
             .enable_rbf();
         let mut psbt = tx_builder.finish()?;
-    let finalized = wallet.sign(&mut psbt, SignOptions::default())?;
+        let finalized = self.wallet.sign(&mut psbt, SignOptions::default())?;
         assert!(finalized);
         let tx = psbt.extract_tx()?;
         Ok(tx)
     }
 
-pub(crate) async fn sync(
-    wallet: &mut Wallet,
-    db: &mut Store<KeychainKind, ConfirmationTimeHeightAnchor>,
-) -> Result<esplora_client::AsyncClient, anyhow::Error> {
+    pub(crate) async fn sync(&mut self) -> Result<(), anyhow::Error> {
         print!("Syncing...");
-    let client = esplora_client::Builder::new("https://mutinynet.com/api")
-        .build_async()
-        .expect("couldn't build esplora client");
-    fn generate_inspect(kind: KeychainKind) -> impl FnMut(u32, &Script) + Send + Sync + 'static {
+
+        fn generate_inspect(
+            kind: KeychainKind,
+        ) -> impl FnMut(u32, &Script) + Send + Sync + 'static {
             let mut once = Some(());
             let mut stdout = std::io::stdout();
             move |spk_i, _| {
@@ -52,7 +59,8 @@ pub(crate) async fn sync(
                 stdout.flush().expect("must flush");
             }
         }
-    let request = wallet
+        let request = self
+            .wallet
             .start_full_scan()
             .inspect_spks_for_all_keychains({
                 let mut once = BTreeSet::<KeychainKind>::new();
@@ -72,34 +80,42 @@ pub(crate) async fn sync(
                 KeychainKind::Internal,
                 generate_inspect(KeychainKind::Internal),
             );
-    let mut update = client
+        let mut update = self
+            .client
             .full_scan(request, STOP_GAP, PARALLEL_REQUESTS)
             .await?;
         let now = std::time::UNIX_EPOCH.elapsed().unwrap().as_secs();
         let _ = update.graph_update.update_last_seen_unconfirmed(now);
-    wallet.apply_update(update)?;
-    if let Some(changeset) = wallet.take_staged() {
-        db.write(&changeset)?;
+        self.wallet.apply_update(update)?;
+        if let Some(changeset) = self.wallet.take_staged() {
+            self.db.write(&changeset)?;
         }
         println!();
-    Ok(client)
+        Ok(())
     }
 
-pub(crate) fn next_unused_address(
-    wallet: &mut Wallet,
-    db: &mut Store<KeychainKind, ConfirmationTimeHeightAnchor>,
-) -> Result<AddressInfo, anyhow::Error> {
-    let address = wallet.next_unused_address(KeychainKind::External);
-    if let Some(changeset) = wallet.take_staged() {
-        db.write(&changeset)?;
+    pub(crate) fn next_unused_address(&mut self) -> Result<AddressInfo, anyhow::Error> {
+        let address = self.wallet.next_unused_address(KeychainKind::External);
+        if let Some(changeset) = self.wallet.take_staged() {
+            self.db.write(&changeset)?;
         }
         println!("Generated Address: {}", address);
         Ok(address)
     }
 
-pub(crate) fn create_wallet(
-    name: &str,
-) -> anyhow::Result<(Wallet, Store<KeychainKind, ConfirmationTimeHeightAnchor>)> {
+    pub(crate) fn balance(&self) -> bdk_wallet::wallet::Balance {
+        self.wallet.balance()
+    }
+
+    pub(crate) async fn broadcast(
+        &self,
+        tx: &bitcoin::Transaction,
+    ) -> Result<(), esplora_client::Error> {
+        self.client.broadcast(tx).await
+    }
+}
+
+pub(crate) fn create_wallet(name: &str) -> anyhow::Result<EsploraWallet> {
     let keys_dir = utils::home(name);
 
     let mnemonic_path = crate::utils::side_paths(keys_dir).1; // TODO: this tuple stinks
@@ -135,5 +151,11 @@ pub(crate) fn create_wallet(
     )
     .expect("problem setting up wallet");
 
-    Ok((wallet, db))
+    let client = esplora_client::Builder::new("https://mutinynet.com/api")
+        .build_async()
+        .expect("couldn't build esplora client");
+
+    let esplora = EsploraWallet { wallet, db, client };
+
+    Ok(esplora)
 }

side-node/src/bitcoin/driver.rs

@@ -11,14 +11,14 @@ use crate::bitcoin::clients;
 /// Also, it very handily works with the mutinynet.com esplora server, which is configured
 /// with 30 second block times.
 pub(crate) async fn run() -> Result<(), anyhow::Error> {
-    let (mut wallet, mut db) = clients::esplora::create_wallet("dave")?;
+    let mut wallet = clients::esplora::create_wallet("dave")?;
 
-    let _next_address = clients::esplora::next_unused_address(&mut wallet, &mut db)?;
+    let _next_address = wallet.next_unused_address()?;
 
     let balance = wallet.balance();
     println!("Wallet balance before syncing: {} sats", balance.total());
 
-    let client = clients::esplora::sync(&mut wallet, &mut db).await?;
+    wallet.sync().await?;
 
     let balance = wallet.balance();
     println!("Wallet balance after syncing: {} sats", balance.total());
@@ -35,8 +35,9 @@ pub(crate) async fn run() -> Result<(), anyhow::Error> {
         std::process::exit(0);
     }
 
-    let tx = clients::esplora::build_send_tx(wallet, faucet_address, send_amount)?;
-    client.broadcast(&tx).await?;
+    let tx = wallet.build_send_tx(faucet_address, send_amount)?;
+    wallet.broadcast(&tx).await?;
+
     println!("Tx broadcasted! Txid: {}", tx.compute_txid());
 
     Ok(())