Merge pull request #147 from ergoplatform/secret-key-to-bytes

Add to_bytes to SecretKey

bindings/ergo-lib-wasm/src/secret_key.rs

@@ -37,6 +37,11 @@ impl SecretKey {
     pub fn get_address(&self) -> Address {
         self.0.get_address_from_public_image().into()
     }
+
+    /// Encode from a serialized key
+    pub fn to_bytes(&self) -> Vec<u8> {
+        self.0.to_bytes()
+    }
 }
 
 impl From<SecretKey> for wallet::secret_key::SecretKey {

ergo-lib/src/sigma_protocol/private_input.rs

@@ -31,6 +31,11 @@ impl DlogProverInput {
             .map(DlogProverInput::from)
     }
 
+    /// byte representation of the underlying scalar
+    pub fn to_bytes(&self) -> [u8; DlogProverInput::SIZE_BYTES] {
+        self.w.to_bytes().into()
+    }
+
     /// public key of discrete logarithm signature protocol
     pub fn public_image(&self) -> ProveDlog {
         // test it, see https://github.com/ergoplatform/sigma-rust/issues/38

ergo-lib/src/wallet/secret_key.rs

@@ -26,6 +26,13 @@ impl SecretKey {
             SecretKey::DlogSecretKey(dpi) => Address::P2PK(dpi.public_image()),
         }
     }
+
+    /// Encode from a serialized key
+    pub fn to_bytes(&self) -> Vec<u8> {
+        match self {
+            SecretKey::DlogSecretKey(key) => key.to_bytes().to_vec(),
+        }
+    }
 }
 
 impl From<SecretKey> for PrivateInput {
@@ -41,3 +48,17 @@ impl From<DlogProverInput> for SecretKey {
         SecretKey::DlogSecretKey(pi)
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::convert::TryInto;
+
+    #[test]
+    fn dlog_roundtrip() {
+        let sk = SecretKey::random_dlog();
+        let sk_copy =
+            SecretKey::dlog_from_bytes(&sk.to_bytes().as_slice().try_into().unwrap()).unwrap();
+        assert_eq!(sk, sk_copy);
+    }
+}