Draft: Resolve "Deal with read-only fields in YANG"

Description

Related Issue

Motivation and Context

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Closes #258 (closed)

controller/nucleus/gnmi_transport.go

@@ -16,7 +16,6 @@ import (
 	"code.fbi.h-da.de/danet/gosdn/forks/goarista/gnmi"
 	gpb "github.com/openconfig/gnmi/proto/gnmi"
 	"github.com/openconfig/goyang/pkg/yang"
-	"github.com/openconfig/ygot/util"
 	"github.com/openconfig/ygot/ygot"
 	"github.com/openconfig/ygot/ytypes"
 	log "github.com/sirupsen/logrus"
@@ -123,41 +122,25 @@ func (g *Gnmi) applyDiff(ctx context.Context, payload change.Payload, path *gpb.
 		return customerrs.NoNewChangesError{Original: payload.Original, Modified: payload.Modified}
 	}
 
-	var json []byte
 	if op := ctx.Value(types.CtxKeyOperation); op == ppb.ApiOperation_API_OPERATION_UPDATE || op == ppb.ApiOperation_API_OPERATION_REPLACE {
-		rootCopy, err := ygot.DeepCopy(schema.Root)
-		if err != nil {
-			return err
-		}
 
+		filteredUpdates := make([]*gpb.Update, 0)
 		for _, u := range diff.Update {
-			opts := []ytypes.SetNodeOpt{&ytypes.InitMissingElements{}, &ytypes.TolerateJSONInconsistencies{}}
-			if err := g.SetNode(schema.RootSchema(), rootCopy, u.GetPath(), u.GetVal(), opts...); err != nil {
+			rootSchema := schema.RootSchema()
+			pathString, err := ygot.PathToString(u.GetPath())
+			if err != nil {
 				return err
 			}
+			entry := rootSchema.Find(pathString)
+			if !entry.ReadOnly() {
+				filteredUpdates = append(filteredUpdates, u)
+			}
 		}
 
-		ygot.PruneEmptyBranches(rootCopy)
-
-		opts := []ytypes.GetNodeOpt{
-			&ytypes.GetHandleWildcards{},
-		}
-		nodes, err := ytypes.GetNode(schema.RootSchema(), rootCopy, path, opts...)
-		if err != nil {
-			return err
-		}
-
-		if len(nodes) == 0 || err != nil || util.IsValueNil(nodes[0].Data) {
-			return customerrs.PathNotFoundError{Path: path, Err: err}
-		}
-
-		json, err = ygot.Marshal7951(nodes[0].Data, &ygot.RFC7951JSONConfig{AppendModuleName: true})
-		if err != nil {
-			return err
-		}
+		diff.Update = filteredUpdates
 	}
 
-	req, err := createSetRequest(ctx, diff, json, path)
+	req, err := createSetRequest(ctx, diff)
 	if err != nil {
 		return err
 	}
@@ -167,25 +150,15 @@ func (g *Gnmi) applyDiff(ctx context.Context, payload change.Payload, path *gpb.
 	return err
 }
 
-func createSetRequest(ctx context.Context, diff *gpb.Notification, json []byte, path *gpb.Path) (*gpb.SetRequest, error) {
+func createSetRequest(ctx context.Context, diff *gpb.Notification) (*gpb.SetRequest, error) {
 	op := ctx.Value(types.CtxKeyOperation)
 	req := &gpb.SetRequest{}
 	if diff.Update != nil {
 		switch op {
 		case ppb.ApiOperation_API_OPERATION_UPDATE:
-			req.Update = []*gpb.Update{{
-				Path: path,
-				Val: &gpb.TypedValue{
-					Value: &gpb.TypedValue_JsonIetfVal{JsonIetfVal: json},
-				},
-			}}
+			req.Update = diff.Update
 		case ppb.ApiOperation_API_OPERATION_REPLACE:
-			req.Replace = []*gpb.Update{{
-				Path: path,
-				Val: &gpb.TypedValue{
-					Value: &gpb.TypedValue_JsonIetfVal{JsonIetfVal: json},
-				},
-			}}
+			req.Replace = diff.Update
 		default:
 			return nil, &customerrs.OperationNotSupportedError{Op: op}
 		}