differentiate between Record creator and author (#893)

Add a property to the `Record` class that denotes the record's `creator`.

When the record is an initial write, the `creator` and `author` will return the same.

Created this issue to add query/filter for creator: decentralized-identity/dwn-sdk-js#800

Author: LiranCohen

.changeset/brown-experts-lay.md

@@ -0,0 +1,5 @@
+---
+"@web5/api": patch
+---
+
+differentiate between Record creator and author

packages/api/src/record.ts

@@ -227,8 +227,10 @@ export class Record implements RecordModel {
 
   // Private variables for DWN `RecordsWrite` message properties.
 
-  /** The DID of the entity that authored the record. */
+  /** The DID of the entity that most recently authored or deleted the record. */
   private _author: string;
+  /** The DID of the entity that originally created the record. */
+  private _creator: string;
   /** Attestation JWS signature. */
   private _attestation?: DwnMessage[DwnInterface.RecordsWrite]['attestation'];
   /** Authorization signature(s). */
@@ -314,6 +316,9 @@ export class Record implements RecordModel {
   /** DID that is the logical author of the Record. */
   get author(): string { return this._author; }
 
+  /** DID that is the original creator of the Record. */
+  get creator(): string { return this._creator; }
+
   /** Record's modified date */
   get dateModified() { return this._descriptor.messageTimestamp; }
 
@@ -368,6 +373,8 @@ export class Record implements RecordModel {
     // Store the author DID that originally signed the message as a convenience for developers, so
     // that they don't have to decode the signer's DID from the JWS.
     this._author = options.author;
+    // The creator is the author of the initial write, or the author of the record if there is no initial write.
+    this._creator = options.initialWrite ? getRecordAuthor(options.initialWrite) : options.author;
 
     // Store the `connectedDid`, and optionally the `delegateDid` and `permissionsApi` in order to be able
     // to perform operations on the record (update, delete, data) as a delegate of the connected DID.

packages/api/tests/record.spec.ts

@@ -2403,6 +2403,51 @@ describe('Record', () => {
   });
 
   describe('update()', () => {
+    let notesProtocol: DwnProtocolDefinition;
+
+    beforeEach(async () => {
+      const protocolUri = `http://example.com/notes-${TestDataGenerator.randomString(15)}`;
+
+      notesProtocol = {
+        published : true,
+        protocol  : protocolUri,
+        types     : {
+          note: {
+            schema: 'http://example.com/note'
+          },
+          request: {
+            schema: 'http://example.com/request'
+          }
+        },
+        structure: {
+          request: {
+            $actions: [{
+              who : 'anyone',
+              can : ['create', 'update', 'delete']
+            },{
+              who : 'recipient',
+              of  : 'request',
+              can : ['co-update']
+            }]
+          },
+          note: {
+          }
+        }
+      };
+
+      // alice and bob both configure the protocol
+      const { status: aliceConfigStatus, protocol: aliceNotesProtocol } = await dwnAlice.protocols.configure({ message: { definition: notesProtocol } });
+      expect(aliceConfigStatus.code).to.equal(202);
+      const { status: aliceNotesProtocolSend } = await aliceNotesProtocol.send(aliceDid.uri);
+      expect(aliceNotesProtocolSend.code).to.equal(202);
+
+      const { status: bobConfigStatus, protocol: bobNotesProtocol } = await dwnBob.protocols.configure({ message: { definition: notesProtocol } });
+      expect(bobConfigStatus.code).to.equal(202);
+      const { status: bobNotesProtocolSend } = await bobNotesProtocol!.send(bobDid.uri);
+      expect(bobNotesProtocolSend.code).to.equal(202);
+
+    });
+
     it('updates a local record on the local DWN', async () => {
       const { status, record } = await dwnAlice.records.write({
         data    : 'Hello, world!',
@@ -2906,6 +2951,64 @@ describe('Record', () => {
       expect(record.dataFormat).to.equal('application/json');
       expect(await record.data.json()).to.deep.equal({ subject: 'another subject', body: 'another body' });
     });
+
+    it('differentiates between creator and author', async () => {
+      const { status, record } = await dwnAlice.records.write({
+        data    : 'Hello, Bob!',
+        message : {
+          recipient    : bobDid.uri,
+          protocol     : notesProtocol.protocol,
+          protocolPath : 'request',
+          schema       : notesProtocol.types.request.schema,
+        }
+      });
+      expect(status.code).to.equal(202, 'create');
+      expect(record).to.not.be.undefined;
+      const { status: sendStatus } = await record.send();
+      expect(sendStatus.code).to.equal(202, 'send');
+
+      // bob reads the record
+      const readResult = await dwnBob.records.read({
+        protocol : notesProtocol.protocol,
+        from     : aliceDid.uri,
+        message  : {
+          filter: {
+            recordId: record.id
+          }
+        }
+      });
+      expect(readResult.status.code).to.equal(200, 'bob reads record');
+      expect(readResult.record).to.not.be.undefined;
+
+      const bobRecord = readResult.record;
+      const { status: storeStatus } = await bobRecord!.store();
+      expect(storeStatus.code).to.equal(202, 'store');
+      const { status: updateStatus } = await bobRecord.update({ data: 'Hello, Alice!' });
+      expect(updateStatus.code).to.equal(202, 'update');
+
+      const updatedData = await bobRecord.send(aliceDid.uri);
+      expect(updatedData.status.code).to.equal(202, 'send update');
+
+      // alice reads the record
+      const readResultAlice = await dwnAlice.records.read({
+        from     : aliceDid.uri,
+        protocol : notesProtocol.protocol,
+        message  : {
+          filter: {
+            recordId: record.id
+          }
+        }
+      });
+
+      expect(readResultAlice.status.code).to.equal(200, 'alice reads record');
+      expect(readResultAlice.record).to.not.be.undefined;
+      expect(await readResultAlice.record!.data.text()).to.equal('Hello, Alice!');
+
+      // alice is the creator
+      expect(readResultAlice.record!.creator).to.equal(aliceDid.uri);
+      // bob is the author
+      expect(readResultAlice.record!.author).to.equal(bobDid.uri);
+    });
   });
 
   describe('delete()', () => {