commented code

nucleus/southbound.go

@@ -82,8 +82,7 @@ func (oc *OpenConfig) Unmarshal(bytes []byte, fields []*path.GnmiPathPiece, goSt
 	return unmarshal(oc.Schema(), bytes, fields, goStruct, opt...)
 }
 
-// unmarshal parses gNMI response to a go struct. If it's a root level response
-// it uses
+//unmarshal parses a gNMI response to a go struct.
 func unmarshal(schema *ytypes.Schema, bytes []byte, fields []*path.GnmiPathPiece, goStruct ygot.ValidatedGoStruct, opt ...ytypes.UnmarshalOpt) error {
 	defer func() {
 		if r := recover(); r != nil {
@@ -160,7 +159,10 @@ func getField(inStruct ygot.ValidatedGoStruct, fields []*path.GnmiPathPiece) (yg
 	return outStruct, nil
 }
 
-// initialiseMapWithKey
+// initialiseMapWithKey takes the map type as reflect.Type (expects it to be a
+// map[T]*L, where T and L can be everything) and the value that should be
+// initialised as reflect.Value. A new map is created and a new key-value pair
+// is set, the newly created value is initialised and returned
 func initialiseMapWithKey(mType reflect.Type, mValue reflect.Value, gpp *path.GnmiPathPiece) (ygot.ValidatedGoStruct, error) {
 	defer func() {
 		if r := recover(); r != nil {
@@ -169,26 +171,31 @@ func initialiseMapWithKey(mType reflect.Type, mValue reflect.Value, gpp *path.Gn
 	}()
 	newMap := reflect.MakeMap(mType)
 	mValue.Set(newMap)
-	// This should only contain one entry. since its a map[T]T the type and
-	// value of the key are not known - therefore it is necessary to loop over
+	// This should only contain one entry. Since its a map[string]string and the
+	// key is not known it is necessary to loop over the map to get the entry
 	for _, k := range gpp.Keys {
-		kConv, err := convertToType(k, mType.Key().Kind())
+		ck, err := convertToType(k, mType.Key().Kind())
 		if err != nil {
 			return nil, err
 		}
-		mValue.SetMapIndex(reflect.ValueOf(kConv), reflect.New(mType.Elem().Elem()))
-		h := mValue.MapIndex(reflect.ValueOf(kConv)).Interface()
+		// Add a new key-value pair with the key from gpp.Keys and a pointer to
+		// a new zero value of type mType.Elem().Elem(), since the map was created
+		// from mType this is the expected ValueType
+		mValue.SetMapIndex(reflect.ValueOf(ck), reflect.New(mType.Elem().Elem()))
+		h := mValue.MapIndex(reflect.ValueOf(ck)).Interface()
 		outStruct, ok := h.(ygot.ValidatedGoStruct)
 		if !ok {
 			return nil, fmt.Errorf("expected ValidatedGoStruct got %v", h)
 		}
+		//Initialise the yang tree of the newly created GoStruct
 		ygot.BuildEmptyTree(outStruct)
 		return outStruct, nil
 	}
 	return nil, fmt.Errorf("could not initialise the map with a key, length of given keys is: %d", len(gpp.Keys))
 }
 
-// TODO: refactor: move somewhere else and check which other types are needed
+// convertToType allows to convert a string to a specific type, which is
+// provided as reflect.Kind
 func convertToType(tc string, k reflect.Kind) (interface{}, error) {
 	switch k {
 	case reflect.String:

nucleus/util/path/translate.go

@@ -6,6 +6,7 @@ import (
 	gpb "github.com/openconfig/gnmi/proto/gnmi"
 )
 
+// GnmiPathPiece represents a piece of a gnmi.Path and holds its Name and Keys
 type GnmiPathPiece struct {
 	Name string
 	Keys map[string]string