From 843d30c88e7eeb9cd2f892316009a5ec279755a4 Mon Sep 17 00:00:00 2001
From: yaoandrew <1547809+yaoandrew@users.noreply.github.com>
Date: Wed, 19 Dec 2018 00:40:00 -0800
Subject: [PATCH] refactor error handling in flip

---
 pkg/transformers/cat_file/flip/repository.go | 34 +++++++++++++-------
 1 file changed, 22 insertions(+), 12 deletions(-)

diff --git a/pkg/transformers/cat_file/flip/repository.go b/pkg/transformers/cat_file/flip/repository.go
index a07ca207..5d305226 100644
--- a/pkg/transformers/cat_file/flip/repository.go
+++ b/pkg/transformers/cat_file/flip/repository.go
@@ -19,6 +19,7 @@ import (
 	"github.com/vulcanize/vulcanizedb/pkg/datastore/postgres"
 	"github.com/vulcanize/vulcanizedb/pkg/transformers/shared"
 	"github.com/vulcanize/vulcanizedb/pkg/transformers/shared/constants"
+	"log"
 )
 
 type CatFileFlipRepository struct {
@@ -26,32 +27,41 @@ type CatFileFlipRepository struct {
 }
 
 func (repository CatFileFlipRepository) Create(headerID int64, models []interface{}) error {
-	tx, err := repository.db.Begin()
-	if err != nil {
-		return err
+	tx, dBaseErr := repository.db.Begin()
+	if dBaseErr != nil {
+		return dBaseErr
 	}
 	for _, model := range models {
 		flip, ok := model.(CatFileFlipModel)
 		if !ok {
-			tx.Rollback()
+			rollbackErr := tx.Rollback()
+			if rollbackErr != nil {
+				log.Println("failed to rollback ", rollbackErr)
+			}
 			return fmt.Errorf("model of type %T, not %T", model, CatFileFlipModel{})
 		}
 
-		_, err = repository.db.Exec(
+		_, execErr := repository.db.Exec(
 			`INSERT into maker.cat_file_flip (header_id, ilk, what, flip, tx_idx, log_idx, raw_log)
 			VALUES($1, $2, $3, $4, $5, $6, $7)`,
 			headerID, flip.Ilk, flip.What, flip.Flip, flip.TransactionIndex, flip.LogIndex, flip.Raw,
 		)
-		if err != nil {
-			tx.Rollback()
-			return err
+		if execErr  != nil {
+			rollbackErr := tx.Rollback()
+			if rollbackErr != nil {
+				log.Println("failed to rollback ", rollbackErr)
+			}
+			return execErr
 		}
 	}
 
-	err = shared.MarkHeaderCheckedInTransaction(headerID, tx, constants.CatFileFlipChecked)
-	if err != nil {
-		tx.Rollback()
-		return err
+	checkHeaderErr := shared.MarkHeaderCheckedInTransaction(headerID, tx, constants.CatFileFlipChecked)
+	if checkHeaderErr != nil {
+		rollbackErr := tx.Rollback()
+		if rollbackErr != nil {
+			log.Println("failed to rollback ", rollbackErr)
+		}
+		return checkHeaderErr
 	}
 	return tx.Commit()
 }