ValidateObject not in interface

mgo.go

@@ -2,12 +2,14 @@ package mgocrud
 
 import (
 	"errors"
+	"runtime"
 
 	mgo "gopkg.in/mgo.v2"
 )
 
 type MgoConnection struct {
 	connection *mgo.Session
+	closed     bool
 }
 
 func NewMgoConnection(dial string) (Connection, error) {
@@ -16,23 +18,44 @@ func NewMgoConnection(dial string) (Connection, error) {
 		return nil, err
 	}
 	connection.SetMode(mgo.Monotonic, true)
-	return &MgoConnection{connection: connection}, nil
+	c := &MgoConnection{connection: connection}
+	runtime.SetFinalizer(c, func(c *MgoConnection) {
+		if !c.closed {
+			c.Close()
+		}
+	})
+	return c, nil
 }
 
 func (c *MgoConnection) Close() {
+	if !c.closed {
 		c.connection.Close()
+		c.closed = true
+	}
+	runtime.SetFinalizer(c, nil)
 }
 
 type MgoSession struct {
 	session *mgo.Session
+	closed  bool
 }
 
 func (s *MgoSession) Close() {
+	if !s.closed {
 		s.session.Close()
+		s.closed = true
+	}
+	runtime.SetFinalizer(s, nil)
 }
 
 func (c *MgoConnection) NewSession() Session {
-	return &MgoSession{session: c.connection.Copy()}
+	s := &MgoSession{session: c.connection.Copy()}
+	runtime.SetFinalizer(s, func(s *MgoSession) {
+		if !s.closed {
+			s.Close()
+		}
+	})
+	return s
 }
 
 type MgoDatabase struct {

setup.go

@@ -9,10 +9,22 @@ import (
 )
 
 // EnsureIndex ensured mongodb index reflecting model struct index tag
-func (db *MgoDatabase) EnsureIndex(m ModelInterface) error {
+func (db *MgoDatabase) EnsureIndex(m ModelInterface, index ...Index) error {
 	colName := GetCollectionName(m)
 	col := db.C(colName)
 
+	if len(index) > 0 {
+		// only ensure given index
+		for _, i := range index {
+			err := col.EnsureIndex(i)
+			if err != nil {
+				return err
+			}
+		}
+		return nil
+	}
+
+	// ensure index by struct fields
 	mType := reflect.TypeOf(m)
 
 	textFields := []string{}

types.go

@@ -22,10 +22,9 @@ type Session interface {
 
 type Database interface {
 	Session() Session
-	C(name string) Collection
+	// C(name string) Collection
 	Name() string
-	EnsureIndex(m ModelInterface) error
-	ValidateObject(m ModelInterface, changes bson.M) error
+	EnsureIndex(m ModelInterface, index ...Index) error
 	ReadDocument(m ModelInterface, selector bson.M) error
 	CreateDocument(m ModelInterface) error
 	ReadCollection(results interface{}, filter bson.M, selector bson.M, offset int, limit int, sort []string, pipelineModifier PipelineModifierFunction) error

validator.go

@@ -6,7 +6,7 @@ import (
 )
 
 // ValidateObject validates object via validator tag and custom method
-func (db *MgoDatabase) ValidateObject(m ModelInterface, changes bson.M) error {
+func ValidateObject(db Database, m ModelInterface, changes bson.M) error {
 	// first validate via struct tag
 	validator := validator.New(&validator.Config{
 		TagName: "validator",