refactor: use macros for pub/private descriptor keys

Author: rustaceanrob

bdk-ffi/src/bdk.udl

@@ -462,44 +462,6 @@ interface DerivationPath {
   constructor(string path);
 };
 
-interface DescriptorSecretKey {
-  constructor(Network network, [ByRef] Mnemonic mnemonic, string? password);
-
-  [Name=from_string, Throws=DescriptorKeyError]
-  constructor(string secret_key);
-
-  [Throws=DescriptorKeyError]
-  DescriptorSecretKey derive([ByRef] DerivationPath path);
-
-  [Throws=DescriptorKeyError]
-  DescriptorSecretKey extend([ByRef] DerivationPath path);
-
-  DescriptorPublicKey as_public();
-
-  sequence<u8> secret_bytes();
-
-  string as_string();
-};
-
-interface DescriptorPublicKey {
-  [Name=from_string, Throws=DescriptorKeyError]
-  constructor(string public_key);
-
-  [Throws=DescriptorKeyError]
-  DescriptorPublicKey derive([ByRef] DerivationPath path);
-
-  [Throws=DescriptorKeyError]
-  DescriptorPublicKey extend([ByRef] DerivationPath path);
-
-  string as_string();
-
-  /// Whether or not this key has multiple derivation paths.
-  boolean is_multipath();
-
-  /// The fingerprint of the master key associated with this key, `0x00000000` if none.
-  string master_fingerprint();
-};
-
 // ------------------------------------------------------------------------
 // bdk-ffi-defined types
 // ------------------------------------------------------------------------

bdk-ffi/src/descriptor.rs

@@ -338,31 +338,31 @@ mod test {
     #[test]
     fn test_descriptor_templates() {
         let master: DescriptorSecretKey = get_descriptor_secret_key();
-        println!("Master: {:?}", master.as_string());
+        println!("Master: {:?}", master.to_string());
         // tprv8ZgxMBicQKsPdWuqM1t1CDRvQtQuBPyfL6GbhQwtxDKgUAVPbxmj71pRA8raTqLrec5LyTs5TqCxdABcZr77bt2KyWA5bizJHnC4g4ysm4h
         let handmade_public_44 = master
             .derive(&DerivationPath::new("m/44h/1h/0h".to_string()).unwrap())
             .unwrap()
             .as_public();
-        println!("Public 44: {}", handmade_public_44.as_string());
+        println!("Public 44: {}", handmade_public_44);
         // Public 44: [d1d04177/44'/1'/0']tpubDCoPjomfTqh1e7o1WgGpQtARWtkueXQAepTeNpWiitS3Sdv8RKJ1yvTrGHcwjDXp2SKyMrTEca4LoN7gEUiGCWboyWe2rz99Kf4jK4m2Zmx/*
         let handmade_public_49 = master
             .derive(&DerivationPath::new("m/49h/1h/0h".to_string()).unwrap())
             .unwrap()
             .as_public();
-        println!("Public 49: {}", handmade_public_49.as_string());
+        println!("Public 49: {}", handmade_public_49);
         // Public 49: [d1d04177/49'/1'/0']tpubDC65ZRvk1NDddHrVAUAZrUPJ772QXzooNYmPywYF9tMyNLYKf5wpKE7ZJvK9kvfG3FV7rCsHBNXy1LVKW95jrmC7c7z4hq7a27aD2sRrAhR/*
         let handmade_public_84 = master
             .derive(&DerivationPath::new("m/84h/1h/0h".to_string()).unwrap())
             .unwrap()
             .as_public();
-        println!("Public 84: {}", handmade_public_84.as_string());
+        println!("Public 84: {}", handmade_public_84);
         // Public 84: [d1d04177/84'/1'/0']tpubDDNxbq17egjFk2edjv8oLnzxk52zny9aAYNv9CMqTzA4mQDiQq818sEkNe9Gzmd4QU8558zftqbfoVBDQorG3E4Wq26tB2JeE4KUoahLkx6/*
         let handmade_public_86 = master
             .derive(&DerivationPath::new("m/86h/1h/0h".to_string()).unwrap())
             .unwrap()
             .as_public();
-        println!("Public 86: {}", handmade_public_86.as_string());
+        println!("Public 86: {}", handmade_public_86);
         // Public 86: [d1d04177/86'/1'/0']tpubDCJzjbcGbdEfXMWaL6QmgVmuSfXkrue7m2YNoacWwyc7a2XjXaKojRqNEbo41CFL3PyYmKdhwg2fkGpLX4SQCbQjCGxAkWHJTw9WEeenrJb/*
         let template_private_44 =
             Descriptor::new_bip44(&master, KeychainKind::External, Network::Testnet);
@@ -405,7 +405,7 @@ mod test {
         println!("Template public 44: {}", template_public_44);
         println!("Template public 84: {}", template_public_84);
         println!("Template public 86: {}", template_public_86);
-        // when using a public key, both to_string and as_string_private return the same string
+        // when using a public key, both to_string and to_string_private return the same string
         assert_eq!(
             template_public_44.to_string_with_secret(),
             template_public_44.to_string()

bdk-ffi/src/keys.rs

@@ -67,10 +67,15 @@ impl DerivationPath {
     }
 }
 
-#[derive(Debug)]
+/// A descriptor containing secret data.
+#[derive(Debug, uniffi::Object)]
+#[uniffi::export(Debug, Display)]
 pub struct DescriptorSecretKey(pub(crate) BdkDescriptorSecretKey);
 
+#[uniffi::export]
 impl DescriptorSecretKey {
+    /// Construct a secret descriptor using a mnemonic.
+    #[uniffi::constructor]
     pub fn new(network: Network, mnemonic: &Mnemonic, password: Option<String>) -> Self {
         let mnemonic = mnemonic.0.clone();
         let xkey: ExtendedKey = (mnemonic, password).into_extended_key().unwrap();
@@ -83,12 +88,15 @@ impl DescriptorSecretKey {
         Self(descriptor_secret_key)
     }
 
+    /// Attempt to parse a string as a descriptor secret key.
+    #[uniffi::constructor]
     pub fn from_string(private_key: String) -> Result<Self, DescriptorKeyError> {
         let descriptor_secret_key = BdkDescriptorSecretKey::from_str(private_key.as_str())
             .map_err(DescriptorKeyError::from)?;
         Ok(Self(descriptor_secret_key))
     }
 
+    /// Derive a descriptor secret key at a given derivation path.
     pub fn derive(&self, path: &DerivationPath) -> Result<Arc<Self>, DescriptorKeyError> {
         let secp = Secp256k1::new();
         let descriptor_secret_key = &self.0;
@@ -116,6 +124,7 @@ impl DescriptorSecretKey {
         }
     }
 
+    /// Extend the descriptor secret key by the derivation path.
     pub fn extend(&self, path: &DerivationPath) -> Result<Arc<Self>, DescriptorKeyError> {
         let descriptor_secret_key = &self.0;
         let path = path.inner_mutex.lock().unwrap().deref().clone();
@@ -135,12 +144,14 @@ impl DescriptorSecretKey {
         }
     }
 
+    /// Return the descriptor public key corresponding to this secret.
     pub fn as_public(&self) -> Arc<DescriptorPublicKey> {
         let secp = Secp256k1::new();
         let descriptor_public_key = self.0.to_public(&secp).unwrap();
         Arc::new(DescriptorPublicKey(descriptor_public_key))
     }
 
+    /// Return the bytes of this descriptor secret key.
     pub fn secret_bytes(&self) -> Vec<u8> {
         let inner = &self.0;
         let secret_bytes: Vec<u8> = match inner {
@@ -157,22 +168,30 @@ impl DescriptorSecretKey {
 
         secret_bytes
     }
+}
 
-    pub fn as_string(&self) -> String {
-        self.0.to_string()
+impl Display for DescriptorSecretKey {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        self.0.fmt(f)
     }
 }
 
-#[derive(Debug)]
+/// A descriptor public key.
+#[derive(Debug, uniffi::Object)]
+#[uniffi::export(Debug, Display)]
 pub struct DescriptorPublicKey(pub(crate) BdkDescriptorPublicKey);
 
+#[uniffi::export]
 impl DescriptorPublicKey {
+    /// Attempt to parse a string as a descriptor public key.
+    #[uniffi::constructor]
     pub fn from_string(public_key: String) -> Result<Self, DescriptorKeyError> {
         let descriptor_public_key = BdkDescriptorPublicKey::from_str(public_key.as_str())
             .map_err(DescriptorKeyError::from)?;
         Ok(Self(descriptor_public_key))
     }
 
+    /// Derive the descriptor public key at the given derivation path.
     pub fn derive(&self, path: &DerivationPath) -> Result<Arc<Self>, DescriptorKeyError> {
         let secp = Secp256k1::new();
         let descriptor_public_key = &self.0;
@@ -201,6 +220,7 @@ impl DescriptorPublicKey {
         }
     }
 
+    /// Extend the descriptor public key by the given derivation path.
     pub fn extend(&self, path: &DerivationPath) -> Result<Arc<Self>, DescriptorKeyError> {
         let descriptor_public_key = &self.0;
         let path = path.inner_mutex.lock().unwrap().deref().clone();
@@ -220,19 +240,23 @@ impl DescriptorPublicKey {
         }
     }
 
-    pub fn as_string(&self) -> String {
-        self.0.to_string()
-    }
-
+    /// Whether or not this key has multiple derivation paths.
     pub fn is_multipath(&self) -> bool {
         self.0.is_multipath()
     }
 
+    /// The fingerprint of the master key associated with this key, `0x00000000` if none.
     pub fn master_fingerprint(&self) -> String {
         self.0.master_fingerprint().to_string()
     }
 }
 
+impl Display for DescriptorPublicKey {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        self.0.fmt(f)
+    }
+}
+
 #[cfg(test)]
 mod test {
     use crate::error::DescriptorKeyError;
@@ -280,38 +304,38 @@ mod test {
     #[test]
     fn test_generate_descriptor_secret_key() {
         let master_dsk = get_inner();
-        assert_eq!(master_dsk.as_string(), "tprv8ZgxMBicQKsPdWuqM1t1CDRvQtQuBPyfL6GbhQwtxDKgUAVPbxmj71pRA8raTqLrec5LyTs5TqCxdABcZr77bt2KyWA5bizJHnC4g4ysm4h/*");
-        assert_eq!(master_dsk.as_public().as_string(), "tpubD6NzVbkrYhZ4WywdEfYbbd62yuvqLjAZuPsNyvzCNV85JekAEMbKHWSHLF9h3j45SxewXDcLv328B1SEZrxg4iwGfmdt1pDFjZiTkGiFqGa/*");
+        assert_eq!(master_dsk.to_string(), "tprv8ZgxMBicQKsPdWuqM1t1CDRvQtQuBPyfL6GbhQwtxDKgUAVPbxmj71pRA8raTqLrec5LyTs5TqCxdABcZr77bt2KyWA5bizJHnC4g4ysm4h/*");
+        assert_eq!(master_dsk.as_public().to_string(), "tpubD6NzVbkrYhZ4WywdEfYbbd62yuvqLjAZuPsNyvzCNV85JekAEMbKHWSHLF9h3j45SxewXDcLv328B1SEZrxg4iwGfmdt1pDFjZiTkGiFqGa/*");
     }
 
     #[test]
     fn test_derive_self() {
         let master_dsk = get_inner();
         let derived_dsk: &DescriptorSecretKey = &derive_dsk(&master_dsk, "m").unwrap();
-        assert_eq!(derived_dsk.as_string(), "[d1d04177]tprv8ZgxMBicQKsPdWuqM1t1CDRvQtQuBPyfL6GbhQwtxDKgUAVPbxmj71pRA8raTqLrec5LyTs5TqCxdABcZr77bt2KyWA5bizJHnC4g4ysm4h/*");
+        assert_eq!(derived_dsk.to_string(), "[d1d04177]tprv8ZgxMBicQKsPdWuqM1t1CDRvQtQuBPyfL6GbhQwtxDKgUAVPbxmj71pRA8raTqLrec5LyTs5TqCxdABcZr77bt2KyWA5bizJHnC4g4ysm4h/*");
         let master_dpk: &DescriptorPublicKey = &master_dsk.as_public();
         let derived_dpk: &DescriptorPublicKey = &derive_dpk(master_dpk, "m").unwrap();
-        assert_eq!(derived_dpk.as_string(), "[d1d04177]tpubD6NzVbkrYhZ4WywdEfYbbd62yuvqLjAZuPsNyvzCNV85JekAEMbKHWSHLF9h3j45SxewXDcLv328B1SEZrxg4iwGfmdt1pDFjZiTkGiFqGa/*");
+        assert_eq!(derived_dpk.to_string(), "[d1d04177]tpubD6NzVbkrYhZ4WywdEfYbbd62yuvqLjAZuPsNyvzCNV85JekAEMbKHWSHLF9h3j45SxewXDcLv328B1SEZrxg4iwGfmdt1pDFjZiTkGiFqGa/*");
     }
 
     #[test]
     fn test_derive_descriptors_keys() {
         let master_dsk = get_inner();
         let derived_dsk: &DescriptorSecretKey = &derive_dsk(&master_dsk, "m/0").unwrap();
-        assert_eq!(derived_dsk.as_string(), "[d1d04177/0]tprv8d7Y4JLmD25jkKbyDZXcdoPHu1YtMHuH21qeN7mFpjfumtSU7eZimFYUCSa3MYzkEYfSNRBV34GEr2QXwZCMYRZ7M1g6PUtiLhbJhBZEGYJ/*");
+        assert_eq!(derived_dsk.to_string(), "[d1d04177/0]tprv8d7Y4JLmD25jkKbyDZXcdoPHu1YtMHuH21qeN7mFpjfumtSU7eZimFYUCSa3MYzkEYfSNRBV34GEr2QXwZCMYRZ7M1g6PUtiLhbJhBZEGYJ/*");
         let master_dpk: &DescriptorPublicKey = &master_dsk.as_public();
         let derived_dpk: &DescriptorPublicKey = &derive_dpk(master_dpk, "m/0").unwrap();
-        assert_eq!(derived_dpk.as_string(), "[d1d04177/0]tpubD9oaCiP1MPmQdndm7DCD3D3QU34pWd6BbKSRedoZF1UJcNhEk3PJwkALNYkhxeTKL29oGNR7psqvT1KZydCGqUDEKXN6dVQJY2R8ooLPy8m/*");
+        assert_eq!(derived_dpk.to_string(), "[d1d04177/0]tpubD9oaCiP1MPmQdndm7DCD3D3QU34pWd6BbKSRedoZF1UJcNhEk3PJwkALNYkhxeTKL29oGNR7psqvT1KZydCGqUDEKXN6dVQJY2R8ooLPy8m/*");
     }
 
     #[test]
     fn test_extend_descriptor_keys() {
         let master_dsk = get_inner();
         let extended_dsk: &DescriptorSecretKey = &extend_dsk(&master_dsk, "m/0").unwrap();
-        assert_eq!(extended_dsk.as_string(), "tprv8ZgxMBicQKsPdWuqM1t1CDRvQtQuBPyfL6GbhQwtxDKgUAVPbxmj71pRA8raTqLrec5LyTs5TqCxdABcZr77bt2KyWA5bizJHnC4g4ysm4h/0/*");
+        assert_eq!(extended_dsk.to_string(), "tprv8ZgxMBicQKsPdWuqM1t1CDRvQtQuBPyfL6GbhQwtxDKgUAVPbxmj71pRA8raTqLrec5LyTs5TqCxdABcZr77bt2KyWA5bizJHnC4g4ysm4h/0/*");
         let master_dpk: &DescriptorPublicKey = &master_dsk.as_public();
         let extended_dpk: &DescriptorPublicKey = &extend_dpk(master_dpk, "m/0").unwrap();
-        assert_eq!(extended_dpk.as_string(), "tpubD6NzVbkrYhZ4WywdEfYbbd62yuvqLjAZuPsNyvzCNV85JekAEMbKHWSHLF9h3j45SxewXDcLv328B1SEZrxg4iwGfmdt1pDFjZiTkGiFqGa/0/*");
+        assert_eq!(extended_dpk.to_string(), "tpubD6NzVbkrYhZ4WywdEfYbbd62yuvqLjAZuPsNyvzCNV85JekAEMbKHWSHLF9h3j45SxewXDcLv328B1SEZrxg4iwGfmdt1pDFjZiTkGiFqGa/0/*");
         let wif = "L2wTu6hQrnDMiFNWA5na6jB12ErGQqtXwqpSL7aWquJaZG8Ai3ch";
         let extended_key = DescriptorSecretKey::from_string(wif.to_string()).unwrap();
         let result = extended_key.derive(&DerivationPath::new("m/0".to_string()).unwrap());
@@ -337,10 +361,10 @@ mod test {
         let master_dsk = get_inner();
         // derive DescriptorSecretKey with path "m/0" from master
         let derived_dsk: &DescriptorSecretKey = &derive_dsk(&master_dsk, "m/0").unwrap();
-        assert_eq!(derived_dsk.as_string(), "[d1d04177/0]tprv8d7Y4JLmD25jkKbyDZXcdoPHu1YtMHuH21qeN7mFpjfumtSU7eZimFYUCSa3MYzkEYfSNRBV34GEr2QXwZCMYRZ7M1g6PUtiLhbJhBZEGYJ/*");
+        assert_eq!(derived_dsk.to_string(), "[d1d04177/0]tprv8d7Y4JLmD25jkKbyDZXcdoPHu1YtMHuH21qeN7mFpjfumtSU7eZimFYUCSa3MYzkEYfSNRBV34GEr2QXwZCMYRZ7M1g6PUtiLhbJhBZEGYJ/*");
         // extend derived_dsk with path "m/0"
         let extended_dsk: &DescriptorSecretKey = &extend_dsk(derived_dsk, "m/0").unwrap();
-        assert_eq!(extended_dsk.as_string(), "[d1d04177/0]tprv8d7Y4JLmD25jkKbyDZXcdoPHu1YtMHuH21qeN7mFpjfumtSU7eZimFYUCSa3MYzkEYfSNRBV34GEr2QXwZCMYRZ7M1g6PUtiLhbJhBZEGYJ/0/*");
+        assert_eq!(extended_dsk.to_string(), "[d1d04177/0]tprv8d7Y4JLmD25jkKbyDZXcdoPHu1YtMHuH21qeN7mFpjfumtSU7eZimFYUCSa3MYzkEYfSNRBV34GEr2QXwZCMYRZ7M1g6PUtiLhbJhBZEGYJ/0/*");
     }
 
     #[test]

bdk-ffi/src/lib.rs

@@ -34,8 +34,6 @@ use crate::error::PsbtParseError;
 use crate::error::RequestBuilderError;
 use crate::error::TransactionError;
 use crate::keys::DerivationPath;
-use crate::keys::DescriptorPublicKey;
-use crate::keys::DescriptorSecretKey;
 use crate::keys::Mnemonic;
 use crate::types::ChainPosition;
 use crate::types::Condition;