flesh out protocolRole and add helper method to extract role

packages/agent/src/utils.ts

@@ -1,5 +1,5 @@
 import type { DidUrlDereferencer } from '@web5/dids';
-import { PaginationCursor, RecordsDeleteMessage, RecordsWriteMessage } from '@tbd54566975/dwn-sdk-js';
+import { Jws, PaginationCursor, RecordsDeleteMessage, RecordsWriteMessage } from '@tbd54566975/dwn-sdk-js';
 
 import { Readable } from '@web5/common';
 import { utils as didUtils } from '@web5/dids';
@@ -42,6 +42,14 @@ export function getRecordAuthor(record: RecordsWriteMessage | RecordsDeleteMessa
   return Message.getAuthor(record);
 }
 
+/**
+ * Get the `protocolRole` string from the signature payload of the given RecordsWriteMessage or RecordsDeleteMessage.
+ */
+export function getRecordProtocolRole(message: RecordsWriteMessage | RecordsDeleteMessage): string | undefined {
+  const signaturePayload = Jws.decodePlainObjectPayload(message.authorization.signature);
+  return signaturePayload?.protocolRole;
+}
+
 export function isRecordsWrite(obj: unknown): obj is RecordsWrite {
   // Validate that the given value is an object.
   if (!obj || typeof obj !== 'object' || obj === null) return false;

packages/agent/tests/utils.spec.ts

@@ -1,7 +1,7 @@
 import { expect } from 'chai';
 
 import { DateSort, Message, TestDataGenerator } from '@tbd54566975/dwn-sdk-js';
-import { getPaginationCursor, getRecordAuthor, getRecordMessageCid } from '../src/utils.js';
+import { getPaginationCursor, getRecordAuthor, getRecordMessageCid, getRecordProtocolRole } from '../src/utils.js';
 
 describe('Utils', () => {
   describe('getPaginationCursor', () => {
@@ -84,4 +84,28 @@ describe('Utils', () => {
       expect(deleteAuthorFromFunction!).to.equal(recordsDeleteAuthor.did);
     });
   });
+
+  describe('getRecordProtocolRole', () => {
+    it('gets a protocol role from a RecordsWrite', async () => {
+      const recordsWrite = await TestDataGenerator.generateRecordsWrite({ protocolRole: 'some-role' });
+      const role = getRecordProtocolRole(recordsWrite.message);
+      expect(role).to.equal('some-role');
+    });
+
+    it('gets a protocol role from a RecordsDelete', async () => {
+      const recordsDelete = await TestDataGenerator.generateRecordsDelete({ protocolRole: 'some-role' });
+      const role = getRecordProtocolRole(recordsDelete.message);
+      expect(role).to.equal('some-role');
+    });
+
+    it('returns undefined if no role is defined', async () => {
+      const recordsWrite = await TestDataGenerator.generateRecordsWrite();
+      const writeRole = getRecordProtocolRole(recordsWrite.message);
+      expect(writeRole).to.be.undefined;
+
+      const recordsDelete = await TestDataGenerator.generateRecordsDelete();
+      const deleteRole = getRecordProtocolRole(recordsDelete.message);
+      expect(deleteRole).to.be.undefined;
+    });
+  });
 });

packages/api/src/dwn-api.ts

@@ -699,7 +699,7 @@ export class DwnApi {
              */
             remoteOrigin : request.from,
             delegateDid  : this.delegateDid,
-            protocolRole : request.message.protocolRole,
+            protocolRole : agentRequest.messageParams.protocolRole,
             ...entry as DwnMessage[DwnInterface.RecordsWrite]
           };
           const record = new Record(this.agent, recordOptions, this.permissionsApi);

packages/api/src/record.ts

@@ -21,6 +21,7 @@ import {
   SendDwnRequest,
   PermissionsApi,
   AgentPermissionsApi,
+  getRecordProtocolRole
 } from '@web5/agent';
 
 import { Convert, isEmptyObject, NodeStream, removeUndefinedProperties, Stream } from '@web5/common';
@@ -150,7 +151,7 @@ export type RecordUpdateParams = {
   datePublished?: DwnMessageDescriptor[DwnInterface.RecordsWrite]['datePublished'];
 
   /** The protocol role under which this record is written. */
-  protocolRole?: string;
+  protocolRole?: RecordOptions['protocolRole'];
 
   /** The published status of the record. */
   published?: DwnMessageDescriptor[DwnInterface.RecordsWrite]['published'];
@@ -224,8 +225,6 @@ export class Record implements RecordModel {
   private _readableStream?: Readable;
   /** The origin DID if the record was fetched from a remote DWN. */
   private _remoteOrigin?: string;
-  /** The protocolRole to use when reading the record */
-  private _protocolRole?: string;
 
   // Private variables for DWN `RecordsWrite` message properties.
 
@@ -251,6 +250,8 @@ export class Record implements RecordModel {
   private _initialWriteSigned: boolean;
   /** Unique identifier of the record. */
   private _recordId: string;
+  /** Role under which the record is written. */
+  private _protocolRole?: RecordOptions['protocolRole'];
 
   /** The `RecordsWriteMessage` descriptor unless the record is in a deleted state */
   private get _recordsWriteDescriptor() {
@@ -330,6 +331,9 @@ export class Record implements RecordModel {
   /** Record's signatures attestation */
   get attestation(): DwnMessage[DwnInterface.RecordsWrite]['attestation'] | undefined { return this._attestation; }
 
+  /** Role under which the author is writing the record */
+  get protocolRole() { return this._protocolRole; }
+
   /** Record's deleted state (true/false) */
   get deleted() { return isDwnMessage(DwnInterface.RecordsDelete, this.rawMessage); }
 
@@ -782,6 +786,7 @@ export class Record implements RecordModel {
 
       // Only update the local Record instance mutable properties if the record was successfully (over)written.
       this._authorization = responseMessage.authorization;
+      this._protocolRole = updateMessage.protocolRole;
       mutableDescriptorProperties.forEach(property => {
         this._descriptor[property] = responseMessage.descriptor[property];
       });
@@ -831,8 +836,7 @@ export class Record implements RecordModel {
 
     // Check to see if the provided protocolRole is different from the current protocolRole
     // If so we need to construct a delete message with the new protocolRole, otherwise we can use the existing
-    // NOTE: currently this is testing the instance _protocolRole, not the actual signature payload.
-    const differentRole = deleteParams?.protocolRole ? this._protocolRole !== deleteParams.protocolRole : false;
+    const differentRole = deleteParams?.protocolRole ? getRecordProtocolRole(this.rawMessage)  !== deleteParams.protocolRole : false;
     if (this.deleted && !differentRole) {
       // if we have a delete message we can just use it
       deleteOptions.rawMessage = this.rawMessage as DwnMessage[DwnInterface.RecordsDelete];