Support reading JsonWebKey-typed keys.

CHANGELOG.md

@@ -1,5 +1,10 @@
 # @digitalbazaar/ed25519-verification-key-2020 ChangeLog
 
+## 4.2.0 - 2024-10-dd
+
+### Added
+- Add support for reading `JsonWebKey`-typed keys.
+
 ## 4.1.0 - 2022-08-09
 
 ### Added

lib/Ed25519VerificationKey2020.js

@@ -1,5 +1,5 @@
 /*!
- * Copyright (c) 2021 Digital Bazaar, Inc. All rights reserved.
+ * Copyright (c) 2021-2024 Digital Bazaar, Inc. All rights reserved.
  */
 import * as base58btc from 'base58-universal';
 import * as base64url from 'base64url-universal';
@@ -92,8 +92,8 @@ export class Ed25519VerificationKey2020 extends LDKeyPair {
     if(options.type === 'Ed25519VerificationKey2018') {
       return Ed25519VerificationKey2020.fromEd25519VerificationKey2018(options);
     }
-    if(options.type === 'JsonWebKey2020') {
-      return Ed25519VerificationKey2020.fromJsonWebKey2020(options);
+    if(options.type === 'JsonWebKey' || options.type === 'JsonWebKey2020') {
+      return Ed25519VerificationKey2020.fromJsonWebKey(options);
     }
     return new Ed25519VerificationKey2020(options);
   }
@@ -144,6 +144,26 @@ export class Ed25519VerificationKey2020 extends LDKeyPair {
     if(type !== 'JsonWebKey2020') {
       throw new TypeError(`Invalid key type: "${type}".`);
     }
+    return Ed25519VerificationKey2020.fromJsonWebKey({
+      id, type, controller, publicKeyJwk
+    });
+  }
+
+  /**
+   * Creates a key pair instance (public key only) from a JsonWebKey object.
+   *
+   * @param {object} options - Options hashmap.
+   * @param {string} options.id - Key id.
+   * @param {string} options.type - Key suite type.
+   * @param {string} options.controller - Key controller.
+   * @param {object} options.publicKeyJwk - JWK object.
+   *
+   * @returns {Promise<Ed25519VerificationKey2020>} Resolves with key pair.
+   */
+  static fromJsonWebKey({id, type, controller, publicKeyJwk} = {}) {
+    if(!(type === 'JsonWebKey' || type === 'JsonWebKey2020')) {
+      throw new TypeError(`Invalid key type: "${type}".`);
+    }
     if(!publicKeyJwk) {
       throw new TypeError('"publicKeyJwk" property is required.');
     }
@@ -331,6 +351,21 @@ export class Ed25519VerificationKey2020 extends LDKeyPair {
       new Uint8Array(await ed25519.sha256digest({data})));
   }
 
+  /**
+   * Returns the JsonWebKey representation of this key pair.
+   *
+   * @returns {Promise<object>} JsonWebKey representation.
+   */
+  async toJsonWebKey() {
+    return {
+      '@context': 'https://w3id.org/security/jwk/v1',
+      id: this.controller + '#' + await this.jwkThumbprint(),
+      type: 'JsonWebKey',
+      controller: this.controller,
+      publicKeyJwk: this.toJwk({publicKey: true})
+    };
+  }
+
   /**
    * Returns the JsonWebKey2020 representation of this key pair.
    *

test/Ed25519VerificationKey2020.spec.js

@@ -1,5 +1,5 @@
 /*!
- * Copyright (c) 2020-2022 Digital Bazaar, Inc. All rights reserved.
+ * Copyright (c) 2020-2024 Digital Bazaar, Inc. All rights reserved.
  */
 import chai from 'chai';
 import * as base58btc from 'base58-universal';
@@ -304,6 +304,52 @@ describe('Ed25519VerificationKey2020', () => {
     });
   });
 
+  describe('JsonWebKey', () => {
+    it('round trip imports/exports', async () => {
+      const keyData = {
+        '@context': 'https://w3id.org/security/jwk/v1',
+        id: 'did:example:123#kPrK_qmxVWaYVA9wwBF6Iuo3vVzz7TxHCTwXBygrS4k',
+        type: 'JsonWebKey',
+        controller: 'did:example:123',
+        publicKeyJwk: {
+          kty: 'OKP',
+          crv: 'Ed25519',
+          x: '11qYAYKxCrfVS_7TyWQHOg7hcvPapiMlrwIaaPcHURo'
+        }
+      };
+
+      const key = await Ed25519VerificationKey2020.from(keyData);
+
+      expect(key.controller).to.equal('did:example:123');
+      expect(key.id).to
+        .equal('did:example:123#kPrK_qmxVWaYVA9wwBF6Iuo3vVzz7TxHCTwXBygrS4k');
+      expect(key.publicKeyMultibase).to
+        .equal('z6MktwupdmLXVVqTzCw4i46r4uGyosGXRnR3XjN4Zq7oMMsw');
+
+      const exported = await key.toJsonWebKey();
+
+      expect(exported).to.eql(keyData);
+    });
+
+    it('computes jwk thumbprint', async () => {
+      const keyData = {
+        id: 'did:example:123#_Qq0UL2Fq651Q0Fjd6TvnYE-faHiOpRlPVQcY_-tA4A',
+        type: 'JsonWebKey',
+        controller: 'did:example:123',
+        publicKeyJwk: {
+          kty: 'OKP',
+          crv: 'Ed25519',
+          x: 'VCpo2LMLhn6iWku8MKvSLg2ZAoC-nlOyPVQaO3FxVeQ'
+        }
+      };
+
+      const key = await Ed25519VerificationKey2020.from(keyData);
+
+      expect(await key.jwkThumbprint()).to
+        .equal('_Qq0UL2Fq651Q0Fjd6TvnYE-faHiOpRlPVQcY_-tA4A');
+    });
+  });
+
   describe('JsonWebKey2020', () => {
     it('round trip imports/exports', async () => {
       const keyData = {