Add storage func for getting a relation between two accounts

storage/accountRelations.go

@@ -10,3 +10,16 @@ type AccountRelation struct {
 	ToId     string
 	Accepted bool
 }
+
+func (s *Storage) GetRelationBetween(fromId, toId string) (*AccountRelation, error) {
+	rel := AccountRelation{}
+	err := s.db.Where(AccountRelation{FromId: fromId, ToId: toId}).First(&rel).Error
+	switch err {
+	case gorm.ErrRecordNotFound:
+		return nil, ErrEntryNotFound
+	case nil:
+		return &rel, nil
+	default:
+		return nil, err
+	}
+}