backoffでmigration時にバックオフリトライする

go.mod

@@ -8,6 +8,7 @@ require (
 	github.com/go-sql-driver/mysql v1.7.0
 	github.com/jinzhu/configor v1.2.1
 	github.com/json-iterator/go v1.1.12
+	github.com/lestrrat-go/backoff/v2 v2.0.8
 	github.com/pkg/errors v0.9.1
 	github.com/r3labs/sse/v2 v2.10.0
 	github.com/rubenv/sql-migrate v1.4.0
@@ -21,6 +22,7 @@ require (
 	github.com/BurntSushi/toml v1.2.1 // indirect
 	github.com/go-gorp/gorp/v3 v3.1.0 // indirect
 	github.com/gorilla/websocket v1.5.0 // indirect
+	github.com/lestrrat-go/option v1.0.0 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
 	go.uber.org/atomic v1.10.0 // indirect

go.sum

@@ -261,6 +261,10 @@ github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
+github.com/lestrrat-go/backoff/v2 v2.0.8 h1:oNb5E5isby2kiro9AgdHLv5N5tint1AnDVVf2E2un5A=
+github.com/lestrrat-go/backoff/v2 v2.0.8/go.mod h1:rHP/q/r9aT27n24JQLa7JhSQZCKBBOiM/uP402WwN8Y=
+github.com/lestrrat-go/option v1.0.0 h1:WqAWL8kh8VcSoD6xjSH34/1m8yxluXQbDeKNfvFeEO4=
+github.com/lestrrat-go/option v1.0.0/go.mod h1:5ZHFbivi4xwXxhxY9XHDe2FHo6/Z7WWmtT7T5nBBp3I=
 github.com/lib/pq v1.10.7 h1:p7ZhMD+KsSRozJr34udlUrhboJwWAgCg34+/ZZNvZZw=
 github.com/lib/pq v1.10.7/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=
 github.com/magiconair/properties v1.8.0/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=

main.go

@@ -3,7 +3,9 @@ package main
 import (
 	"context"
 	"database/sql"
+	"errors"
 	"fmt"
+	"time"
 
 	_ "github.com/go-sql-driver/mysql"
 	"github.com/jinzhu/configor"
@@ -15,6 +17,7 @@ import (
 	"github.com/kounoike/dtv-discord-go/dtv"
 	"github.com/kounoike/dtv-discord-go/mirakc/mirakc_client"
 	"github.com/kounoike/dtv-discord-go/mirakc/mirakc_handler"
+	"github.com/lestrrat-go/backoff/v2"
 	migrate "github.com/rubenv/sql-migrate"
 	"go.uber.org/zap"
 	"go.uber.org/zap/zapcore"
@@ -56,14 +59,34 @@ func main() {
 
 	logger.Info("Starting dtv-discord-go", zap.String("version", version))
 
+	p := backoff.Exponential(
+		backoff.WithMinInterval(time.Second),
+		backoff.WithMaxInterval(time.Minute),
+		backoff.WithJitterFactor(0.05),
+	)
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+
 	db, err := sql.Open("mysql", fmt.Sprintf("%s:%s@tcp(%s)/%s?charset=utf8mb4&collation=utf8mb4_general_ci&parseTime=true", config.DB.User, config.DB.Password, config.DB.Host, config.DB.Name))
 	if err != nil {
 		logger.Error("can't connect to db server", zap.Error(err))
 		return
 	}
 	queries := sqlcdb.New(db)
 	migrations := migrate.FileMigrationSource{Dir: "db/migrations"}
-	n, err := migrate.Exec(db, "mysql", migrations, migrate.Up)
+
+	retryMigrationFunc := func(db *sql.DB, migrations migrate.FileMigrationSource) (int, error) {
+		b := p.Start(ctx)
+		for backoff.Continue(b) {
+			n, err := migrate.Exec(db, "mysql", migrations, migrate.Up)
+			if err == nil {
+				return n, nil
+			}
+		}
+		return 0, errors.New("failed to migration")
+	}
+
+	n, err := retryMigrationFunc(db, migrations)
 	if err != nil {
 		logger.Error("db migration error", zap.Error(err))
 		return
@@ -94,7 +117,6 @@ func main() {
 
 	discordHandler := discord_handler.NewDiscordHandler(usecase, discordClient.Session(), logger)
 
-	ctx := context.Background()
 	err = usecase.InitializeServiceChannels(ctx)
 	if err != nil {
 		logger.Error("can't create program infomation channel", zap.Error(err))