Digest hash (#56)

* encodeDidUrl: the identifier as HexString, and prefix is `did:zk`.

* encode did when calc digest hash

.changeset/angry-coins-shake.md

@@ -0,0 +1,5 @@
+---
+'@zcloak/vc': minor
+---
+
+encode did when calc digest

.changeset/wild-foxes-serve.md

@@ -0,0 +1,5 @@
+---
+'@zcloak/did': minor
+---
+
+encodeDidUrl: the identifier as HexString, and prefix is `did:zk`.

packages/did/src/did/details.ts

@@ -8,6 +8,8 @@ import { assert } from '@polkadot/util';
 
 import { parseDid } from '@zcloak/did-resolver/parseDid';
 
+import { encodeDidUrl } from '../utils';
+
 export abstract class DidDetails implements IDidDetails {
   public id: DidUrl;
   public identifier: string;
@@ -64,4 +66,8 @@ export abstract class DidDetails implements IDidDetails {
 
     return method;
   }
+
+  public encodeDidUrl(): Uint8Array {
+    return encodeDidUrl(this.id);
+  }
 }

packages/did/src/index.ts

@@ -7,3 +7,4 @@ export * as helpers from './did/helpers';
 export * as keys from './keys';
 
 export * from './hasher';
+export * from './utils';

packages/did/src/utils.spec.ts

@@ -0,0 +1,36 @@
+// Copyright 2021-2023 zcloak authors & contributors
+// SPDX-License-Identifier: Apache-2.0
+
+import { alice } from 'test-support';
+
+import { initCrypto } from '@zcloak/crypto';
+
+import { encodeDidUrl } from './utils';
+
+describe('Did utils', (): void => {
+  beforeAll(async () => {
+    await initCrypto();
+  });
+
+  it('encode did url', () => {
+    const encoded = encodeDidUrl(alice.id);
+
+    expect(encoded).toEqual(
+      new Uint8Array([
+        100, 105, 100, 58, 122, 107, 58, 17, 248, 183, 127, 52, 252, 241, 75, 112, 149, 191, 82, 40,
+        172, 6, 6, 50, 78, 130, 209
+      ])
+    );
+  });
+
+  it('encode did has fragment', () => {
+    const encoded = encodeDidUrl(alice.getKeyUrl('authentication'));
+
+    expect(encoded).toEqual(
+      new Uint8Array([
+        100, 105, 100, 58, 122, 107, 58, 17, 248, 183, 127, 52, 252, 241, 75, 112, 149, 191, 82, 40,
+        172, 6, 6, 50, 78, 130, 209
+      ])
+    );
+  });
+});

packages/did/src/utils.ts

@@ -4,6 +4,8 @@
 import type { DidUrl, VerificationMethodType } from '@zcloak/did-resolver/types';
 import type { KeypairType } from '@zcloak/keyring/types';
 
+import { stringToU8a, u8aConcat } from '@polkadot/util';
+
 import { parseDid } from '@zcloak/did-resolver/parseDid';
 
 /**
@@ -48,3 +50,24 @@ export function typeTransform(type: KeypairType): VerificationMethodType {
       throw new Error(`Can not transform type: ${type}`);
   }
 }
+
+/**
+ * @name encodeDidUrl
+ * @summary
+ * encode `didUrl` to a bytes.
+ * @description
+ * encode `didUrl` to bytes with the identifier as HexString, and the prefix is `did:zk:`. Returns `Uint8Array`.
+ * @example
+ * ```typescript
+ * import { encodeDidUrl } from '@zcloak/did'
+ *
+ * encodeDidUrl('did:zk:0x11f8b77F34FCF14B7095BF5228Ac0606324E82D1'); // [...]
+ * ```
+ */
+export function encodeDidUrl(didUrl: DidUrl): Uint8Array {
+  const { identifier, method } = parseDid(didUrl);
+
+  const prefix = stringToU8a(`did:${method}:`);
+
+  return u8aConcat(prefix, identifier);
+}

packages/vc/src/digest.ts

@@ -7,6 +7,8 @@ import type { HashType, VerifiableCredentialVersion } from './types';
 
 import { numberToU8a, stringToU8a, u8aConcat, u8aToHex } from '@polkadot/util';
 
+import { encodeDidUrl } from '@zcloak/did';
+
 import { DEFAULT_DIGEST_HASH_TYPE } from './defaults';
 import { HASHER } from './hasher';
 
@@ -73,7 +75,7 @@ export function calcDigest<Version extends VerifiableCredentialVersion>(
   } else {
     encoded = u8aConcat(
       payload.rootHash,
-      stringToU8a(payload.holder),
+      encodeDidUrl(payload.holder),
       numberToU8a((payload as DigestPayload<'1'>).issuanceDate),
       numberToU8a(payload.expirationDate || 0),
       payload.ctype