feat(local-signing-manager): add derivationPath for account (#33)

* feat(local-signing-manager): add `derivationPath` for account
PolymeshAssociation · Feb 6, 2023 · af131b6 · af131b6
1 parent e9387a9
commit af131b6
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Showing 3 changed files with 95 additions and 13 deletions.
diff --git a/packages/local-signing-manager/src/lib/local-signing-manager.spec.ts b/packages/local-signing-manager/src/lib/local-signing-manager.spec.ts
@@ -116,6 +116,74 @@ describe('LocalSigningManager Class', () => {
         "Cannot call 'addAccount' before calling 'setSs58Format'. Did you forget to use this Signing Manager to connect with the Polymesh SDK?"
       );
     });
+
+    it('should add a new Account(by seed) with a derivation path', async () => {
+      signingManager = await LocalSigningManager.create({
+        accounts: [
+          {
+            seed: '0xb5da7610352f87452fe5fa4d9af35a3fbb613e7afee2c72056333db0b94d6f98',
+            derivationPath: '//test',
+          },
+        ],
+      });
+
+      signingManager.setSs58Format(42);
+
+      expect((await signingManager.getAccounts())[0]).toBe(
+        '5FQwqu3rSRgr48cKxvU9zhumx2iAbtQp8NvRA99j8DKgdFua'
+      );
+    });
+
+    it('should add a new Account(by uri) with a derivation path', async () => {
+      signingManager = await LocalSigningManager.create({
+        accounts: [
+          {
+            uri: '//Alice',
+            derivationPath: '//test',
+          },
+        ],
+      });
+
+      signingManager.setSs58Format(42);
+
+      expect((await signingManager.getAccounts())[0]).toBe(
+        '5DfkbGYYVW5DHGrZtiAWVF6umYUTpYMPuhXhcAMor8nPGmJG'
+      );
+    });
+
+    it('should add a new Account(by mnemonic) with a derivation path', async () => {
+      signingManager = await LocalSigningManager.create({
+        accounts: [
+          {
+            mnemonic:
+              'bachelor nurse busy spot cannon equal drip outer autumn fork virtual thunder',
+            derivationPath: '//test',
+          },
+        ],
+      });
+
+      signingManager.setSs58Format(42);
+
+      expect((await signingManager.getAccounts())[0]).toBe(
+        '5FbhYPC4ShEdEpKjv37ZvVpJ68nuCTNbRShWmg8iSVCEpwmr'
+      );
+    });
+
+    it('should throw an error if the soft path was provided on `ed25519` curve type', async () => {
+      expect(
+        async () =>
+          await LocalSigningManager.create({
+            accounts: [
+              {
+                mnemonic:
+                  'bachelor nurse busy spot cannon equal drip outer autumn fork virtual thunder',
+                derivationPath: '//hard/soft',
+              },
+            ],
+            type: 'ed25519',
+          })
+      ).rejects.toThrow('A soft key was found in the path and is not supported');
+    });
   });
 
   describe('method: generateAccount', () => {

diff --git a/packages/local-signing-manager/src/lib/local-signing-manager.ts b/packages/local-signing-manager/src/lib/local-signing-manager.ts
@@ -190,11 +190,27 @@ export class LocalSigningManager implements SigningManager {
     let address: string;
 
     if ('uri' in account) {
-      ({ address } = keyring.addFromUri(account.uri));
+      const accountUri = account.derivationPath
+        ? `${account.uri}${account.derivationPath}`
+        : account.uri;
+      address = keyring.addFromUri(accountUri).address;
     } else if ('mnemonic' in account) {
-      ({ address } = keyring.addFromMnemonic(account.mnemonic));
+      const accountMnemonic = account.derivationPath
+        ? `${account.mnemonic}${account.derivationPath}`
+        : account.mnemonic;
+      address = keyring.addFromUri(accountMnemonic).address;
     } else {
-      ({ address } = keyring.addFromSeed(hexToU8a(account.seed)));
+      const seedInU8a = hexToU8a(account.seed);
+
+      if (account.derivationPath) {
+        address = keyring.addPair(
+          new Keyring({ type: this.keyring.type })
+            .addFromSeed(seedInU8a)
+            .derive(account.derivationPath)
+        ).address;
+      } else {
+        address = keyring.addFromSeed(seedInU8a).address;
+      }
     }
 
     return address;

diff --git a/packages/local-signing-manager/src/types/index.ts b/packages/local-signing-manager/src/types/index.ts
@@ -1,16 +1,14 @@
 /**
  * URI|mnemonic|hex representation of a private key
  */
-export type PrivateKey =
-  | {
-      uri: string;
-    }
-  | {
-      mnemonic: string;
-    }
-  | {
-      seed: string;
-    };
+export type PrivateKey = ({ uri: string } | { mnemonic: string } | { seed: string }) & {
+  /**
+   * (optional) a specify a derivation path to apply to the secret. This allows for multiple accounts to be created with only one secret
+   *
+   * @note if using this option the account can only be recreated by knowing the path and the secret. Be sure to use a consistent scheme when making the path
+   */
+  derivationPath?: string;
+};
 
 /**
  * Supported key types. Generally `sr25519` is preferred, but `ed25519` is more widely supported