refactor: use protojson for policy evaluations bundle serialization

Signed-off-by: Miguel Martinez Trivino <miguel@chainloop.dev>

Author: migmartri

app/cli/pkg/action/attestation_push.go

@@ -38,7 +38,6 @@ import (
 	protobundle "github.com/sigstore/protobuf-specs/gen/pb-go/bundle/v1"
 	"google.golang.org/grpc"
 	"google.golang.org/protobuf/encoding/protojson"
-	"google.golang.org/protobuf/proto"
 	"google.golang.org/protobuf/types/known/timestamppb"
 )
 
@@ -365,15 +364,15 @@ func uploadPolicyEvaluationsBundle(ctx context.Context, evaluations []*v1.Policy
 	}
 
 	bundle := &v1.PolicyEvaluationBundle{Evaluations: evaluations}
-	data, err := proto.Marshal(bundle)
+	data, err := protojson.Marshal(bundle)
 	if err != nil {
 		return nil, fmt.Errorf("marshaling policy evaluation bundle: %w", err)
 	}
 
 	hexDigest := fmt.Sprintf("%x", sha256.Sum256(data))
 	digest := fmt.Sprintf("sha256:%s", hexDigest)
 
-	if _, err := uploader.Upload(ctx, bytes.NewReader(data), "policy-evaluations.pb", digest); err != nil {
+	if _, err := uploader.Upload(ctx, bytes.NewReader(data), "policy-evaluations.json", digest); err != nil {
 		return nil, fmt.Errorf("uploading policy evaluation bundle: %w", err)
 	}
 

app/cli/pkg/action/attestation_push_test.go

@@ -28,7 +28,7 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/mock"
 	"github.com/stretchr/testify/require"
-	"google.golang.org/protobuf/proto"
+	"google.golang.org/protobuf/encoding/protojson"
 )
 
 func TestUploadPolicyEvaluationsBundle(t *testing.T) {
@@ -64,9 +64,9 @@ func TestUploadPolicyEvaluationsBundle(t *testing.T) {
 			uploader: func(t *testing.T) casclient.Uploader {
 				t.Helper()
 				m := casclientmock.NewUploader(t)
-				m.On("Upload", mock.Anything, mock.Anything, "policy-evaluations.pb", mock.MatchedBy(func(digest string) bool {
+				m.On("Upload", mock.Anything, mock.Anything, "policy-evaluations.json", mock.MatchedBy(func(digest string) bool {
 					return len(digest) > 7 && digest[:7] == "sha256:"
-				})).Return(&casclient.UpDownStatus{Filename: "policy-evaluations.pb"}, nil)
+				})).Return(&casclient.UpDownStatus{Filename: "policy-evaluations.json"}, nil)
 				return m
 			},
 			wantRef: true,
@@ -113,7 +113,7 @@ func TestUploadPolicyEvaluationsBundle(t *testing.T) {
 
 			// Verify the digest matches what we'd expect from serializing the bundle
 			bundle := &v1.PolicyEvaluationBundle{Evaluations: tc.evaluations}
-			data, err := proto.Marshal(bundle)
+			data, err := protojson.Marshal(bundle)
 			require.NoError(t, err)
 			expectedDigest := fmt.Sprintf("%x", sha256.Sum256(data))
 			assert.Equal(t, expectedDigest, ref.Digest["sha256"])

pkg/attestation/renderer/chainloop/v02.go

@@ -38,7 +38,7 @@ import (
 // Replace custom material type with https://github.com/in-toto/attestation/blob/main/spec/v1.0/resource_descriptor.md
 const PredicateTypeV02 = "chainloop.dev/attestation/v0.2"
 const AttPolicyEvaluation = "CHAINLOOP.ATTESTATION"
-const PolicyEvaluationsBundleMediaType = "application/vnd.chainloop.policy-evaluations.v1+proto"
+const PolicyEvaluationsBundleMediaType = "application/vnd.chainloop.policy-evaluations.v1+json"
 
 type ProvenancePredicateV02 struct {
 	*ProvenancePredicateCommon