Add PrivateKey.toBytes method

src/types/keypair/PrivateKey.ts

@@ -5,12 +5,13 @@ import { PrivateKey as Ed25519PrivateKey } from './ed25519/PrivateKey';
 import { PrivateKey as Secp256k1PrivateKey } from './secp256k1/PrivateKey';
 
 /**
- * Interface representing the structure of a private key, with methods for
- * obtaining the public key, signing messages, and exporting to PEM format.
+ * Interface representing the structure and methods of a private key, including
+ * functions to retrieve public key bytes, sign messages, and export to PEM format.
  */
-interface PrivateKeyInternal {
+export interface PrivateKeyInternal {
   /** Retrieves the public key bytes. */
   publicKeyBytes(): Promise<Uint8Array>;
+  toBytes(): Uint8Array;
 
   /**
    * Signs a message using the private key.
@@ -57,6 +58,10 @@ export class PrivateKey {
     this.priv = priv;
   }
 
+  toBytes(): Uint8Array {
+    return this.priv.toBytes();
+  }
+
   /**
    * Gets the public key associated with this private key.
    * @returns The associated PublicKey instance.

src/types/keypair/ed25519/PrivateKey.ts

@@ -1,23 +1,5 @@
 import * as ed25519 from '@noble/ed25519';
-
-/**
- * Interface representing the structure and methods of a private key, including
- * functions to retrieve public key bytes, sign messages, and export to PEM format.
- */
-interface PrivateKeyInternal {
-  /** Retrieves the public key bytes. */
-  publicKeyBytes(): Promise<Uint8Array>;
-
-  /**
-   * Signs a message using the private key.
-   * @param message - The message to sign.
-   * @returns A promise that resolves to the signature bytes.
-   */
-  sign(message: Uint8Array): Promise<Uint8Array>;
-
-  /** Converts the private key to PEM format. */
-  toPem(): string;
-}
+import { PrivateKeyInternal } from "../PrivateKey";
 
 /**
  * Represents an Ed25519 private key, supporting key generation, signing, and PEM encoding.
@@ -55,6 +37,10 @@ export class PrivateKey implements PrivateKeyInternal {
     return ed25519.getPublicKey(this.key);
   }
 
+  toBytes(): Uint8Array {
+    return this.key;
+  }
+
   /**
    * Signs a message using the private key.
    * @param message - The message to sign.

src/types/keypair/secp256k1/PrivateKey.ts

@@ -1,31 +1,13 @@
 import * as secp256k1 from '@noble/secp256k1';
 import { sha256 } from '@noble/hashes/sha256';
+import { PrivateKeyInternal } from "../PrivateKey";
 
 /** PEM prefix for a private key. */
 const PemPrivateKeyPrefix = '-----BEGIN PRIVATE KEY-----';
 
 /** PEM suffix for a private key. */
 const PemPrivateKeySuffix = '-----END PRIVATE KEY-----';
 
-/**
- * Interface representing the structure and methods of a private key, including
- * functions to retrieve public key bytes, sign messages, and export to PEM format.
- */
-interface PrivateKeyInternal {
-  /** Retrieves the public key bytes. */
-  publicKeyBytes(): Promise<Uint8Array>;
-
-  /**
-   * Signs a message using the private key.
-   * @param message - The message to sign.
-   * @returns A promise resolving to the signature bytes.
-   */
-  sign(message: Uint8Array): Promise<Uint8Array>;
-
-  /** Converts the private key to PEM format. */
-  toPem(): string;
-}
-
 /**
  * Represents a secp256k1 private key, supporting key generation, signing, and PEM encoding.
  * The class offers static methods to create instances from bytes, hex, and PEM formats.
@@ -67,6 +49,10 @@ export class PrivateKey implements PrivateKeyInternal {
     return secp256k1.getPublicKey(this.key, true);
   }
 
+  toBytes(): Uint8Array {
+    return this.key;
+  }
+
   /**
    * Signs a message using the private key.
    * The message is first hashed with SHA-256 before signing.