feat: batch generate key pair

Signed-off-by: Berend Sliedrecht <[email protected]>

biome.json

@@ -25,7 +25,12 @@
     "enabled": true
   },
   "linter": {
-    "enabled": true
+    "enabled": true,
+    "rules": {
+      "performance": {
+        "noAccumulatingSpread": "off"
+      }
+    }
   },
   "vcs": {
     "useIgnoreFile": true,

src/ExpoSecureEnvironmentModule.ts

@@ -0,0 +1,49 @@
+import { requireNativeModule } from 'expo-modules-core'
+import type { SecureEnvironment } from './SecureEnvironment'
+
+type UnwrapPromiseReturnTypes<T, ExcludedKey extends keyof T = never> = {
+  [K in keyof T]: K extends ExcludedKey
+    ? T[K]
+    : T[K] extends (...args: infer A) => Promise<infer R> | infer S
+      ? (...args: A) => Promise<R> extends Promise<infer U> ? U : Promise<R> | S
+      : T[K]
+}
+
+const nativeExpoSecureEnvironment = requireNativeModule<
+  UnwrapPromiseReturnTypes<Omit<SecureEnvironment, 'batchGenerateKeyPair'>, 'sign'> & {
+    supportsSecureEnvironment: () => boolean
+  }
+>('ExpoSecureEnvironment')
+
+export const expoSecureEnvironment = {
+  generateKeypair: (keyId: string, biometricsBacked?: boolean): Uint8Array => {
+    nativeExpoSecureEnvironment.generateKeypair(keyId, biometricsBacked)
+    const publicKey = expoSecureEnvironment.getPublicBytesForKeyId(keyId)
+    return publicKey
+  },
+
+  batchGenerateKeyPair: (keyIds: Array<string>): Record<string, Uint8Array> => {
+    for (const keyId of keyIds) {
+      expoSecureEnvironment.generateKeypair(keyId)
+    }
+
+    return keyIds
+      .map((keyId) => ({
+        keyId,
+        publicKey: expoSecureEnvironment.getPublicBytesForKeyId(keyId),
+      }))
+      .reduce((prev, curr) => ({ ...prev, [curr.keyId]: curr.publicKey }), {})
+  },
+
+  getPublicBytesForKeyId: (keyId: string): Uint8Array => {
+    return nativeExpoSecureEnvironment.getPublicBytesForKeyId(keyId)
+  },
+
+  sign: (keyId: string, message: Uint8Array, biometricsBacked?: boolean): Promise<Uint8Array> => {
+    return nativeExpoSecureEnvironment.sign(keyId, message, biometricsBacked)
+  },
+
+  supportsSecureEnvironment: () => {
+    return nativeExpoSecureEnvironment.supportsSecureEnvironment()
+  },
+}

src/SecureEnvironment.ts

@@ -5,14 +5,22 @@
  *
  */
 
-import { Platform, requireNativeModule } from 'expo-modules-core'
-
-const expoSecureEnvironment = requireNativeModule<SecureEnvironment & { supportsSecureEnvironment: () => boolean }>(
-  'ExpoSecureEnvironment'
-)
+import { Platform } from 'expo-modules-core'
+import { expoSecureEnvironment } from './ExpoSecureEnvironmentModule'
 
 export interface SecureEnvironment {
-  generateKeypair(id: string, biometricsBacked?: boolean): Promise<void> | void
+  generateKeypair(keyId: string, biometricsBacked?: boolean): Promise<Uint8Array> | Uint8Array
+  /**
+   *
+   * @todo Might be better to make this optional
+   *
+   * Returns an object where each key is the `keyId` and the value is the public key bytes
+   *
+   */
+  batchGenerateKeyPair(
+    keyIds: Array<string>,
+    biometricsBacked?: boolean
+  ): Promise<Record<string, Uint8Array>> | Record<string, Uint8Array>
   getPublicBytesForKeyId(keyId: string): Promise<Uint8Array> | Uint8Array
   sign(keyId: string, message: Uint8Array, biometricsBacked?: boolean): Promise<Uint8Array>
 }