Update migration model for using with different drivers

model/migration.go

@@ -2,6 +2,7 @@ package model
 
 import (
 	"github.com/jmoiron/sqlx"
+	"os"
 	"time"
 )
 
@@ -13,34 +14,134 @@ type Migration struct {
 }
 
 func CreateMigrationsTable(connection *sqlx.DB) bool {
-	_, err := connection.Exec("SELECT * FROM migrations LIMIT 1")
+	_, err := connection.Exec(checkTableExitSQL())
 	if err != nil {
-		connection.MustExec("CREATE TABLE migrations (id int auto_increment, name varchar(255) not null, batch int not null, created_at datetime default current_timestamp not null, constraint migrations_pk primary key (id));")
+		connection.MustExec(creteTableSQL())
 		return true
 	}
 	return false
 }
 
 func AddMigrationRaw(connection *sqlx.DB, migration string, lastBatch int) {
-	connection.MustExec("INSERT INTO migrations (name, batch) VALUES (?, ?)", migration, lastBatch)
+	connection.MustExec(addRawSQL(), migration, lastBatch)
+}
+
+func MigrationExist(connection *sqlx.DB, name string) bool {
+	var raw Migration
+	err := connection.Get(&raw, getRawSQL(), name)
+	if err != nil {
+		return false
+	}
+	return true
 }
 
 func GetLastBatch(connection *sqlx.DB) int {
 	var raw Migration
-	_ = connection.Get(&raw, "SELECT * FROM migrations ORDER BY batch DESC LIMIT 1")
+	_ = connection.Get(&raw, getLastBatchSQL())
 	return raw.Batch
 }
 
 func GetLastMigrations(connection *sqlx.DB, lastBatch int) []*Migration {
 	var list []*Migration
-	_ = connection.Select(&list, "SELECT * FROM migrations WHERE batch=? ORDER BY created_at DESC, id DESC;", lastBatch)
+	err := connection.Select(&list, getLastRawSQL(), lastBatch)
+	if err != nil {
+		panic(err)
+	}
 	return list
 }
 
 func RemoveMigrationRaw(connection *sqlx.DB, migration string) {
-	connection.MustExec("DELETE FROM migrations WHERE name=?", migration)
+	connection.MustExec(removeMigrationSQL(), migration)
 }
 
 func RemoveLastBatch(connection *sqlx.DB, lastBatch int) {
-	connection.MustExec("DELETE FROM migrations WHERE batch=?", lastBatch)
+	connection.MustExec(removeBatchSQL(), lastBatch)
+}
+
+func checkTableExitSQL() string {
+	switch os.Getenv("DB_DRIVER") {
+	case "mysql":
+		return "SELECT * FROM migrations LIMIT 1;"
+	case "postgres":
+		return "SELECT * FROM migrations LIMIT 1;"
+	default:
+		panic("Not supported DB driver: " + os.Getenv("DB_DRIVER"))
+	}
+}
+
+func creteTableSQL() string {
+	switch os.Getenv("DB_DRIVER") {
+	case "mysql":
+		return "CREATE TABLE migrations (id int auto_increment, name varchar(255) not null, batch int not null, created_at datetime default current_timestamp not null, constraint migrations_pk primary key (id));"
+	case "postgres":
+		return "CREATE TABLE migrations (id serial PRIMARY KEY, name varchar(255) not null, batch int not null, created_at TIMESTAMP WITH TIME ZONE DEFAULT CURRENT_TIMESTAMP not null);"
+	default:
+		panic("Not supported DB driver: " + os.Getenv("DB_DRIVER"))
+	}
+}
+
+func getRawSQL() string {
+	switch os.Getenv("DB_DRIVER") {
+	case "mysql":
+		return "SELECT * FROM migrations WHERE name=?;"
+	case "postgres":
+		return "SELECT * FROM migrations WHERE name=$1;"
+	default:
+		panic("Not supported DB driver: " + os.Getenv("DB_DRIVER"))
+	}
+}
+
+func addRawSQL() string {
+	switch os.Getenv("DB_DRIVER") {
+	case "mysql":
+		return "INSERT INTO migrations (name, batch) VALUES (?, ?);"
+	case "postgres":
+		return "INSERT INTO migrations (name, batch) VALUES ($1, $2);"
+	default:
+		panic("Not supported DB driver: " + os.Getenv("DB_DRIVER"))
+	}
+}
+
+func getLastBatchSQL() string {
+	switch os.Getenv("DB_DRIVER") {
+	case "mysql":
+		return "SELECT * FROM migrations ORDER BY batch DESC LIMIT 1;"
+	case "postgres":
+		return "SELECT * FROM migrations ORDER BY batch DESC LIMIT 1;"
+	default:
+		panic("Not supported DB driver: " + os.Getenv("DB_DRIVER"))
+	}
+}
+
+func getLastRawSQL() string {
+	switch os.Getenv("DB_DRIVER") {
+	case "mysql":
+		return "SELECT * FROM migrations WHERE batch=? ORDER BY created_at DESC, id DESC;"
+	case "postgres":
+		return "SELECT * FROM migrations WHERE batch=$1 ORDER BY created_at DESC, id DESC;"
+	default:
+		panic("Not supported DB driver: " + os.Getenv("DB_DRIVER"))
+	}
+}
+
+func removeBatchSQL() string {
+	switch os.Getenv("DB_DRIVER") {
+	case "mysql":
+		return "DELETE FROM migrations WHERE batch=?;"
+	case "postgres":
+		return "DELETE FROM migrations WHERE batch=$1;"
+	default:
+		panic("Not supported DB driver: " + os.Getenv("DB_DRIVER"))
+	}
+}
+
+func removeMigrationSQL() string {
+	switch os.Getenv("DB_DRIVER") {
+	case "mysql":
+		return "DELETE FROM migrations WHERE name=$1"
+	case "postgres":
+		return ""
+	default:
+		panic("Not supported DB driver: " + os.Getenv("DB_DRIVER"))
+	}
 }