chore: make extra signers auditable in dlog metadata

plan.md

@@ -0,0 +1,18 @@
+# Implementation Plan - Token Metadata Regression Pipeline
+
+## Goal
+Implement a regression testing pipeline to ensure backward compatibility for token requests and metadata validation across protocol versions V1, V2, and V3.
+
+## Implementation Progress
+- [x] Create fixture generator for V1/V2/V3 metadata
+- [x] Implement regression test suite for `AuditCheck`
+- [x] Fix type mismatches in validator test environment
+- [x] Fix identity string representation in `Match` error messages
+- [x] Verify all tests pass locally
+
+## Notes & Decisions
+- Decided to use `auditor_test` package for regression tests to avoid circular dependencies.
+- Added hashed/base64 identity strings to `metadata_test.go` to match the new `AuditableIdentity` behavior.
+- Protocol V3 fixtures include `AuditableIdentity` for both issuer and extra signers.
+
+✅ COMPLETE

token/core/fabtoken/v1/transfer.go

@@ -166,7 +166,7 @@ func (s *TransferService) Transfer(ctx context.Context, anchor driver.TokenReque
 		Inputs:       transferInputsMetadata,
 		Outputs:      transferOutputsMetadata,
 		ExtraSigners: nil,
-		Issuer:       nil,
+		Issuer:       driver.AuditableIdentity{},
 	}
 
 	if isRedeem {
@@ -175,7 +175,7 @@ func (s *TransferService) Transfer(ctx context.Context, anchor driver.TokenReque
 			return nil, nil, errors.Wrap(err, "failed to select issuer for redeem")
 		}
 		transfer.Issuer = issuer
-		transferMetadata.Issuer = issuer
+		transferMetadata.Issuer = driver.AuditableIdentity{Identity: issuer}
 	}
 
 	return transfer, transferMetadata, nil

token/core/zkatdlog/nogh/v1/transfer.go

@@ -255,6 +255,7 @@ func (s *TransferService) Transfer(ctx context.Context, anchor driver.TokenReque
 		Inputs:       transferInputsMetadata,
 		Outputs:      transferOutputsMetadata,
 		ExtraSigners: nil,
+		Issuer:       driver.AuditableIdentity{},
 	}
 
 	// 8. If this is a redeem, select an issuer who can authorize it.
@@ -264,7 +265,7 @@ func (s *TransferService) Transfer(ctx context.Context, anchor driver.TokenReque
 			return nil, nil, errors.Wrap(err, "failed to select issuer for redeem")
 		}
 		transfer.Issuer = issuer
-		transferMetadata.Issuer = issuer
+		transferMetadata.Issuer = driver.AuditableIdentity{Identity: issuer}
 	}
 
 	return transfer, transferMetadata, nil

token/core/zkatdlog/nogh/v1/validator/testutils/env.go

@@ -557,7 +557,7 @@ func prepareTransfer(
 	tokns[0] = append(tokns[0], tokens...)
 
 	if issuerIdentity != nil {
-		metadata.Issuer = issuerIdentity
+		metadata.Issuer = driver.AuditableIdentity{Identity: issuerIdentity}
 	}
 
 	transferMetadata := &driver.TokenRequestMetadata{Transfers: []*driver.TransferMetadata{metadata}}