From 2a07781d225dd8766e97b16f9edd607ea14959db Mon Sep 17 00:00:00 2001
From: IWAMOTO Toshihiro <iwamoto@valinux.co.jp>
Date: Mon, 29 Oct 2018 14:09:10 +0900
Subject: [PATCH] Only retry an INSERT operation on unique constraint violation

The retry logic is used to generate an unique ID, but if there is
another error the DB code can fall into an infinite loop.

Signed-off-by: IWAMOTO Toshihiro <iwamoto@valinux.co.jp>
---
 pkg/db/interface.go | 45 ++++++++++++++++++++++++---------------------
 1 file changed, 24 insertions(+), 21 deletions(-)

diff --git a/pkg/db/interface.go b/pkg/db/interface.go
index 004b5006598..420503b004f 100644
--- a/pkg/db/interface.go
+++ b/pkg/db/interface.go
@@ -109,6 +109,14 @@ func generateRandid() string {
 	return string(rs1Letters[rand.Intn(len(rs1Letters))]) + fmt.Sprintf("%016x", id)[1:]
 }
 
+func isDBDuplicateError(err error) bool {
+	errmsg := strings.ToLower(err.Error())
+	if strings.Contains(errmsg, "unique") || strings.Contains(errmsg, "duplicate") {
+		return true
+	}
+	return false
+}
+
 func (d *dbConn) GetStudyConfig(id string) (*api.StudyConfig, error) {
 	row := d.db.QueryRow("SELECT * FROM studies WHERE id = ?", id)
 
@@ -240,13 +248,10 @@ func (d *dbConn) CreateStudy(in *api.StudyConfig) (string, error) {
 		)
 		if err == nil {
 			break
-		} else {
-			errmsg := strings.ToLower(err.Error())
-			if strings.Contains(errmsg, "unique") || strings.Contains(errmsg, "duplicate") {
-				i--
-				if i > 0 {
-					continue
-				}
+		} else if isDBDuplicateError(err) {
+			i--
+			if i > 0 {
+				continue
 			}
 		}
 		return "", err
@@ -387,13 +392,10 @@ func (d *dbConn) CreateTrial(trial *api.Trial) error {
 		if err == nil {
 			trial.TrialId = trialID
 			break
-		} else {
-			errmsg := strings.ToLower(err.Error())
-			if strings.Contains(errmsg, "unique") || strings.Contains(errmsg, "duplicate") {
-				i--
-				if i > 0 {
-					continue
-				}
+		} else if isDBDuplicateError(err) {
+			i--
+			if i > 0 {
+				continue
 			}
 		}
 		return err
@@ -728,13 +730,10 @@ func (d *dbConn) CreateWorker(worker *api.Worker) (string, error) {
 		if err == nil {
 			worker.WorkerId = workerID
 			break
-		} else {
-			errmsg := strings.ToLower(err.Error())
-			if strings.Contains(errmsg, "unique") || strings.Contains(errmsg, "duplicate") {
-				i--
-				if i > 0 {
-					continue
-				}
+		} else if isDBDuplicateError(err) {
+			i--
+			if i > 0 {
+				continue
 			}
 		}
 		return "", err
@@ -917,6 +916,8 @@ func (d *dbConn) SetSuggestionParam(algorithm string, studyID string, params []*
 			paramID, algorithm, studyID, strings.Join(ps, ",\n"))
 		if err == nil {
 			break
+		} else if !isDBDuplicateError(err) {
+			return "", err
 		}
 	}
 	return paramID, err
@@ -1025,6 +1026,8 @@ func (d *dbConn) SetEarlyStopParam(algorithm string, studyID string, params []*a
 			paramID, algorithm, studyID, strings.Join(ps, ",\n"))
 		if err == nil {
 			break
+		} else if !isDBDuplicateError(err) {
+			return "", err
 		}
 	}
 	return paramID, nil