update vc sign (#332)

* update vc sign

* fix spec

* support signing with secp256k1 and ed25519 keys

* remove unused import

* add did ion test

---------

Co-authored-by: Moe Jangda <moe@tbd.email>

.web5-spec/credentials.ts

@@ -1,58 +1,27 @@
 import { Request, Response } from 'express';
-import { VerifiableCredential, SignOptions } from '@web5/credentials';
-import { DidKeyMethod, PortableDid } from '@web5/dids';
-import { Ed25519, PrivateKeyJwk } from '@web5/crypto';
+import { VerifiableCredential } from '@web5/credentials';
+import { DidKeyMethod } from '@web5/dids';
 import { paths } from './openapi.js';
 
-type Signer = (data: Uint8Array) => Promise<Uint8Array>;
-
-let _ownDid: PortableDid;
-
-async function getOwnDid(): Promise<PortableDid> {
-    if(_ownDid) {
-        return _ownDid;
-    }
-    _ownDid = await DidKeyMethod.create();
-    return _ownDid;
-}
-
 export async function credentialIssue(req: Request, res: Response) {
   const body: paths["/credentials/issue"]["post"]["requestBody"]["content"]["application/json"] =
   req.body;
 
-    const ownDid = await getOwnDid()
-
-    // build signing options
-    const [signingKeyPair] = ownDid.keySet.verificationMethodKeys!;
-    const subjectIssuerDid = body.credential.credentialSubject["id"] as string;
-    const signer = EdDsaSigner(signingKeyPair.privateKeyJwk as PrivateKeyJwk);
-    const signOptions: SignOptions = {
-        issuerDid  : ownDid.did,
-        subjectDid : subjectIssuerDid,
-        kid        : '#' + ownDid.did.split(':')[2],
-        signer     : signer
-    };
+  const ownDid = await DidKeyMethod.create();
 
   const vc: VerifiableCredential = VerifiableCredential.create({
     type: body.credential.type[body.credential.type.length - 1],
     issuer: body.credential.issuer,
-    subject: subjectIssuerDid,
+    subject: body.credential.credentialSubject["id"] as string,
     data: body.credential.credentialSubject
   });
 
-  const vcJwt: string = await vc.sign(signOptions);
+  const vcJwt: string = await vc.sign({did: ownDid});
 
   const resp: paths["/credentials/issue"]["post"]["responses"]["200"]["content"]["application/json"] =
       {
         verifiableCredential: {data: vcJwt}
       };
 
   res.json(resp);
-}
-
-function EdDsaSigner(privateKey: PrivateKeyJwk): Signer {
-    return async (data: Uint8Array): Promise<Uint8Array> => {
-        const signature = await Ed25519.sign({ data, key: privateKey});
-        return signature;
-    };
 }