feat: add keyIdentifier.derive()

libraries/key-identifier/__tests__/key-identifier.test.js

@@ -22,7 +22,6 @@ describe('KeyIdentifier', () => {
         assetName: 0,
         derivationPath: "m/44'/60'/0'/0/0",
       },
-
       // Non-existing assetNames
       // {
       //  derivationAlgorithm: 'BIP32',
@@ -70,6 +69,53 @@ describe('KeyIdentifier', () => {
     invalid.forEach((item) => expect(KeyIdentifier.validate(item)).toEqual(false))
   })
 
+  it('supports passing the derivation path as array of path indices', () => {
+    const keyId = new KeyIdentifier({
+      derivationAlgorithm: 'BIP32',
+      assetName: 'ethereum',
+      derivationPath: ['m', "44'", "60'", "0'", '0', '0'],
+    })
+
+    expect(keyId.derivationPath).toBe("m/44'/60'/0'/0/0")
+  })
+
+  describe('.extend()', () => {
+    test('extends derivation path', () => {
+      const keyId = new KeyIdentifier({
+        derivationAlgorithm: 'BIP32',
+        assetName: 'ethereum',
+        derivationPath: "m/44'/60'/0'",
+      })
+
+      const derived = keyId.derive([1, 5])
+
+      expect(derived).toEqual({
+        derivationAlgorithm: 'BIP32',
+        assetName: 'ethereum',
+        keyType: 'secp256k1',
+      })
+
+      expect(derived.derivationPath).toBe("m/44'/60'/0'/1/5")
+    })
+  })
+
+  describe('.toJSON()', () => {
+    test('includes derivation path', () => {
+      const keyId = new KeyIdentifier({
+        derivationAlgorithm: 'BIP32',
+        assetName: 'ethereum',
+        derivationPath: "m/44'/60'/0'",
+      })
+
+      expect(keyId.toJSON()).toEqual({
+        derivationAlgorithm: 'BIP32',
+        assetName: 'ethereum',
+        keyType: 'secp256k1',
+        derivationPath: "m/44'/60'/0'",
+      })
+    })
+  })
+
   describe('.compare()', () => {
     it('should return true when equal', () => {
       const keyIdA = new KeyIdentifier({

libraries/key-identifier/package.json

@@ -25,7 +25,7 @@
     "todo:reenable:test:integration": "jest --testMatch='**/*.integration-test.js'"
   },
   "dependencies": {
-    "@exodus/key-utils": "^3.1.0",
+    "@exodus/key-utils": "^3.3.0",
     "minimalistic-assert": "^1.0.1"
   },
   "devDependencies": {

libraries/key-identifier/src/key-identifier.d.ts

@@ -1,20 +1,38 @@
+type PathIndex = number | string
+type KeyType = 'legacy' | 'nacl' | 'secp2561'
+type DerivationAlgorithm = 'BIP32' | 'SLIP10'
+
 type ConstructorParams = {
-  derivationAlgorithm: 'BIP32' | 'SLIP10'
-  derivationPath: string
+  derivationAlgorithm: DerivationAlgorithm
+  derivationPath: string | PathIndex[]
   assetName?: string
-  keyType: 'legacy' | 'nacl' | 'secp2561'
+  keyType: KeyType
 }
 
 type KeyIdentifierLike = Partial<ConstructorParams>
 
 export default class KeyIdentifier {
-  derivationAlgorithm: ConstructorParams['derivationAlgorithm']
-  derivationPath: ConstructorParams['derivationPath']
-  assetName: ConstructorParams['assetName']
-  keyType: ConstructorParams['keyType']
+  derivationAlgorithm: DerivationAlgorithm
+  keyType: KeyType
+  assetName?: string
 
   constructor(params: ConstructorParams)
 
+  get derivationPath(): string
+
+  /**
+   * Returns a new KeyIdentifier instance that has an updated derivation path extended with
+   * the path indices or partial derivation path supplied to this method
+   */
+  derive(pathLike: string | PathIndex[]): KeyIdentifier
+
+  toJSON(): {
+    assetName?: string
+    derivationAlgorithm: DerivationAlgorithm
+    keyType: KeyType
+    derivationPath: string
+  }
+
   static validate(potentialKeyIdentifier: KeyIdentifierLike): boolean
   static compare(a: KeyIdentifierLike, b: KeyIdentifierLike): boolean
 }

libraries/key-identifier/src/key-identifier.js

@@ -1,26 +1,25 @@
 import assert from 'minimalistic-assert'
-import { assertValidDerivationPath } from '@exodus/key-utils'
-
-// key identifier example:
-// {
-//   derivationAlgorithm: 'BIP32',
-//   derivationPath: `m/44'/60'/0'/0/0`
-//   // needed because some assets like `ethereum` and `matic` share the same constant but may have other differences
-//   assetName: 'solana'
-// }
+import { DerivationPath } from '@exodus/key-utils'
+
 const SUPPORTED_KDFS = new Set(['BIP32', 'SLIP10'])
 const SUPPORTED_KEY_TYPES = new Set(['legacy', 'nacl', 'secp256k1'])
 
+const isDerivationPath = (derivationPath) =>
+  typeof derivationPath === 'object' &&
+  Symbol.toStringTag in derivationPath &&
+  derivationPath[Symbol.toStringTag]() === 'DerivationPath'
+
 export default class KeyIdentifier {
+  /** @type {DerivationPath} */
+  #derivationPath
+
   constructor({ derivationAlgorithm, derivationPath, assetName, keyType }) {
     assert(typeof derivationAlgorithm === 'string', 'derivationAlgorithm not a string')
     assert(
       SUPPORTED_KDFS.has(derivationAlgorithm),
       `${derivationAlgorithm} is not a valid derivationAlgorithm`
     )
 
-    assertValidDerivationPath(derivationPath)
-
     assert(['string', 'undefined'].includes(typeof assetName), 'assetName was not a string')
 
     keyType = keyType || (derivationAlgorithm === 'SLIP10' ? 'nacl' : 'secp256k1')
@@ -34,19 +33,41 @@ export default class KeyIdentifier {
     }
 
     this.derivationAlgorithm = derivationAlgorithm
-    this.derivationPath = derivationPath
     this.assetName = assetName
     this.keyType = keyType
+    this.#derivationPath = isDerivationPath(derivationPath)
+      ? derivationPath
+      : DerivationPath.from(derivationPath)
 
     // Freeze the object on construction, disallow tampering with derivation path.
     // Ensures immutability of key identifiers passed to keychain.
     Object.freeze(this)
   }
 
+  get derivationPath() {
+    return this.#derivationPath.toString()
+  }
+
+  derive(pathLike) {
+    return new KeyIdentifier({
+      ...this,
+      derivationPath: this.#derivationPath.extend(pathLike),
+    })
+  }
+
   toString() {
     return `${this.derivationPath} (${this.derivationAlgorithm})`
   }
 
+  toJSON() {
+    return {
+      derivationAlgorithm: this.derivationAlgorithm,
+      assetName: this.assetName,
+      keyType: this.keyType,
+      derivationPath: this.derivationPath,
+    }
+  }
+
   static validate = (potentialKeyIdentifier) => {
     try {
       // eslint-disable-next-line no-new

yarn.lock

@@ -1975,7 +1975,7 @@ __metadata:
   resolution: "@exodus/key-identifier@workspace:libraries/key-identifier"
   dependencies:
     "@exodus/key-ids": ^1.2.0
-    "@exodus/key-utils": ^3.1.0
+    "@exodus/key-utils": ^3.3.0
     "@exodus/keychain": "workspace:^"
     minimalistic-assert: ^1.0.1
   languageName: unknown
@@ -2001,7 +2001,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@exodus/key-utils@npm:^3.0.0, @exodus/key-utils@npm:^3.1.0":
+"@exodus/key-utils@npm:^3.0.0":
   version: 3.1.0
   resolution: "@exodus/key-utils@npm:3.1.0"
   dependencies:
@@ -2012,6 +2012,18 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@exodus/key-utils@npm:^3.3.0":
+  version: 3.3.0
+  resolution: "@exodus/key-utils@npm:3.3.0"
+  dependencies:
+    "@exodus/bip32": ^2.1.0
+    "@exodus/hdkey": ^2.1.0-exodus.0
+    bip32-path: ^0.4.2
+    minimalistic-assert: ^1.0.1
+  checksum: 741e47ac4e2fe285cd984c41dd27508cf2ece46ad53c7afd2f8a6358b9952ef1cedb05839b4f1a3949da19850f051409829f30e45d3fa137856852239018d953
+  languageName: node
+  linkType: hard
+
 "@exodus/keychain@npm:^5.0.1":
   version: 5.0.1
   resolution: "@exodus/keychain@npm:5.0.1"