Commit-Confirm Mechanic for PND

Description

This MR introduces a commit-confirm mechanic for changes to ONDs. A change created in a pending-state. A commit of this change by the operator pushed the change to the given OND. If the commit is not confirmed within 10 minutes (default. Use the GOSDN_CHANGE_TIMEOUT environment variable to change the timeout) is is rolled back automatically.

Related Issue

Closes #99 (closed)

Motivation and Context

How Has This Been Tested?

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.

nucleus/gnmi_transport.go

@@ -2,19 +2,21 @@ package nucleus
 
 import (
 	"code.fbi.h-da.de/cocsn/gosdn/forks/goarista/gnmi"
+	pathutils "code.fbi.h-da.de/cocsn/gosdn/nucleus/util/path"
 	"context"
 	gpb "github.com/openconfig/gnmi/proto/gnmi"
 	"github.com/openconfig/gnmi/proto/gnmi_ext"
 	"github.com/openconfig/goyang/pkg/yang"
+	"github.com/openconfig/ygot/ygot"
 	"github.com/openconfig/ygot/ytypes"
 	log "github.com/sirupsen/logrus"
 	"reflect"
-	"strings"
 )
 
 // CtxKeyType is a custom type to be used as key in a context.WithValue() or
 // context.Value() call. For more information see:
 // https://www.calhoun.io/pitfalls-of-context-values-and-how-to-avoid-or-mitigate-them/
+// TODO: Unexport to comply with best practice
 type CtxKeyType string
 
 const (
@@ -22,8 +24,16 @@ const (
 	CtxKeyOpts CtxKeyType = "opts"
 	// CtxKeyConfig is a context key for gnmi.Config
 	CtxKeyConfig = "config"
+	// CtxKeyOperation is a context key for a gNMI operation (update, replace, delete)
+	CtxKeyOperation = "op"
 )
 
+var opmap = map[Operation]string{
+	TransportUpdate:  "update",
+	TransportReplace: "replace",
+	TransportDelete:  "delete",
+}
+
 // Gnmi implements the Transport interface and provides an SBI with the
 // possibility to access a gNMI endpoint.
 type Gnmi struct {
@@ -75,22 +85,55 @@ func (g *Gnmi) Get(ctx context.Context, params ...string) (interface{}, error) {
 
 // Set takes a slice of params. This slice must contain at least one operation.
 // It can contain an additional arbitrary amount of operations and extensions.
-func (g *Gnmi) Set(ctx context.Context, args ...interface{}) (interface{}, error) {
+func (g *Gnmi) Set(ctx context.Context, args ...interface{}) error {
 	if g.client == nil {
-		return nil, &ErrNilClient{}
+		return &ErrNilClient{}
 	}
 	if len(args) == 0 {
-		return nil, &ErrInvalidParameters{
+		return &ErrInvalidParameters{
 			f: "gnmi.Set()",
 			r: "no parameters provided",
 		}
 	}
 
+	if len(args) == 2 {
+		switch args[0].(type) {
+		case ygot.GoStruct:
+			return g.applyDiff(ctx, args[0])
+		default:
+
+		}
+	}
+
+	opts := make([]interface{}, 0)
+	for _, o := range args {
+		attrs, ok := o.([]string)
+		if !ok {
+			return &ErrInvalidTypeAssertion{
+				v: o,
+				t: reflect.TypeOf("placeholder"),
+			}
+		} else if attrs == nil || len(attrs) == 0 {
+			return &ErrInvalidParameters{
+				f: "gnmi.Set()",
+				r: "no parameters provided",
+			}
+		}
+		opts = append(opts, &gnmi.Operation{
+			// Hardcoded TransportUpdate until multiple operations are supported
+			Type:   opmap[TransportUpdate],
+			Origin: "",
+			Target: "",
+			Path:   gnmi.SplitPath(attrs[0]),
+			Val:    attrs[1],
+		})
+	}
+
 	// Loop over args and create ops and exts
 	// Invalid args cause unhealable error
 	ops := make([]*gnmi.Operation, 0)
 	exts := make([]*gnmi_ext.Extension, 0)
-	for _, p := range args {
+	for _, p := range opts {
 		switch p.(type) {
 		case *gnmi.Operation:
 			op := p.(*gnmi.Operation)
@@ -101,19 +144,66 @@ func (g *Gnmi) Set(ctx context.Context, args ...interface{}) (interface{}, error
 		case *gnmi_ext.Extension:
 			exts = append(exts, p.(*gnmi_ext.Extension))
 		default:
-			return nil, &ErrInvalidParameters{
+			return &ErrInvalidParameters{
 				f: "gnmi.Set()",
 				r: "args contain invalid type",
 			}
 		}
 	}
 	if len(ops) == 0 {
-		return nil, &ErrInvalidParameters{
+		return &ErrInvalidParameters{
 			f: "gnmi.Set()",
 			r: "no operations provided",
 		}
 	}
-	return g.set(ctx, ops, exts...)
+	resp, err := g.set(ctx, ops, exts...)
+	if err != nil {
+		return err
+	}
+	log.Info(resp)
+	return nil
+}
+
+func (g *Gnmi) applyDiff(ctx context.Context, payload ...interface{}) error {
+	if len(payload) != 2 {
+		return &ErrInvalidParameters{}
+	}
+	op := ctx.Value(CtxKeyOperation)
+	oldstate, ok := payload[0].(ygot.GoStruct)
+	if !ok {
+		return &ErrInvalidTypeAssertion{
+			v: payload[0],
+			t: reflect.TypeOf("ygot.GoStruct"),
+		}
+	}
+	newstate, ok := payload[1].(ygot.GoStruct)
+	if !ok {
+		return &ErrInvalidTypeAssertion{
+			v: payload[1],
+			t: reflect.TypeOf("ygot.GoStruct"),
+		}
+	}
+
+	diff, err := ygot.Diff(oldstate, newstate)
+	if err != nil {
+		return err
+	}
+	req := &gpb.SetRequest{}
+	if diff.Update != nil {
+		switch op {
+		case TransportUpdate:
+			req.Update = diff.Update
+		case TransportReplace:
+			req.Replace = diff.Update
+		default:
+			return &ErrOperationNotSupported{}
+		}
+	} else if diff.Delete != nil {
+		req.Delete = diff.Delete
+	}
+	resp, err := g.client.Set(ctx, req)
+	log.Info(resp)
+	return err
 }
 
 //Subscribe subscribes to a gNMI target
@@ -141,7 +231,7 @@ func (g *Gnmi) ProcessResponse(resp interface{}, root interface{}, s *ytypes.Sch
 			val, ok := update.Val.Value.(*gpb.TypedValue_JsonIetfVal)
 			if ok {
 				opts := []ytypes.UnmarshalOpt{&ytypes.IgnoreExtraFields{}}
-				if err := g.Unmarshal(val.JsonIetfVal, extraxtPathElements(fullPath), root, opts...); err != nil {
+				if err := g.Unmarshal(val.JsonIetfVal, pathutils.ToStrings(fullPath), root, opts...); err != nil {
 					return err
 				}
 				return nil
@@ -157,14 +247,6 @@ func (g *Gnmi) ProcessResponse(resp interface{}, root interface{}, s *ytypes.Sch
 	return nil
 }
 
-func extraxtPathElements(path *gpb.Path) []string {
-	elems := make([]string, len(path.Elem))
-	for i, e := range path.Elem {
-		elems[i] = strings.Title(e.Name)
-	}
-	return elems
-}
-
 // Capabilities calls GNMI capabilities
 func (g *Gnmi) Capabilities(ctx context.Context) (interface{}, error) {
 	log.WithFields(log.Fields{