added support to login user oauth user by email only (#6330)

* added support to login user oauth user by email only

* added sql handler

* fixed model method name from GetUserByEmail to GetUserByEmailQuery

* fixed variable declaration typo

pkg/services/sqlstore/user.go

@@ -19,6 +19,7 @@ func init() {
 	bus.AddHandler("sql", UpdateUser)
 	bus.AddHandler("sql", ChangeUserPassword)
 	bus.AddHandler("sql", GetUserByLogin)
+	bus.AddHandler("sql", GetUserByEmail)
 	bus.AddHandler("sql", SetUsingOrg)
 	bus.AddHandler("sql", GetUserProfile)
 	bus.AddHandler("sql", GetSignedInUser)
@@ -193,6 +194,27 @@ func GetUserByLogin(query *m.GetUserByLoginQuery) error {
 	return nil
 }
 
+func GetUserByEmail(query *m.GetUserByEmailQuery) error {
+	if query.Email == "" {
+		return m.ErrUserNotFound
+	}
+
+	user := new(m.User)
+
+	user = &m.User{Email: query.Email}
+	has, err := x.Get(user)
+
+	if err != nil {
+		return err
+	} else if has == false {
+		return  m.ErrUserNotFound
+	}
+
+	query.Result = user
+
+	return nil
+}
+
 func UpdateUser(cmd *m.UpdateUserCommand) error {
 	return inTransaction2(func(sess *session) error {