New API tested

storage/driver/boltdb.go

@@ -316,7 +316,29 @@ func applySet(doc, operator bson.M) (bson.M, error) {
 		if k == entity.Name {
 			return nil, errModifiedReserved
 		}
-		doc[k] = v
+		nesting := strings.Split(k, ".")
+		if len(nesting) > 1 {
+			mInterface, ok := doc[nesting[0]]
+			if !ok {
+				return nil, fmt.Errorf("path does not exist: %s (%s): %+v", k, nesting[0], doc)
+			}
+			m, ok := mInterface.(map[string]interface{})
+			if !ok {
+				pm, pmok := mInterface.(primitive.M)
+				m = map[string]interface{}(pm)
+				ok = pmok
+			}
+			if !ok {
+				return nil, fmt.Errorf("subpath cannot be followed for non object: %s (%s): %+v (%T)", k, nesting[0], mInterface, mInterface)
+			}
+			subdoc, err := applySet(bson.M(m), bson.M{strings.Join(nesting[1:], "."): v})
+			if err != nil {
+				return nil, err
+			}
+			doc[nesting[0]] = subdoc
+		} else {
+			doc[k] = v
+		}
 	}
 	return doc, nil
 }