feat: support NewAdapterWithoutAutoMigrate (#160)

* feat: support NewAdapterWithoutAutoMigrate

Signed-off-by: tangyang9464 <tangyang9464@163.com>

* Update adapter_test.go

Co-authored-by: Yang Luo <hsluoyz@qq.com>

adapter.go

@@ -39,6 +39,8 @@ const (
 
 type customTableKey struct{}
 
+const disableMigrateKey = "disableMigrateKey"
+
 type CasbinRule struct {
 	ID    uint   `gorm:"primaryKey;autoIncrement"`
 	Ptype string `gorm:"size:100"`
@@ -195,9 +197,13 @@ func NewAdapterByDBUseTableName(db *gorm.DB, prefix string, tableName string) (*
 	}
 
 	a.db = db.Scopes(a.casbinRuleTable()).Session(&gorm.Session{Context: db.Statement.Context})
-	err := a.createTable()
-	if err != nil {
-		return nil, err
+
+	disableMigrate := a.db.Statement.Context.Value(disableMigrateKey)
+	if disableMigrate == nil {
+		err := a.createTable()
+		if err != nil {
+			return nil, err
+		}
 	}
 
 	return a, nil
@@ -249,6 +255,17 @@ func NewAdapterByDB(db *gorm.DB) (*Adapter, error) {
 	return NewAdapterByDBUseTableName(db, "", defaultTableName)
 }
 
+func NewAdapterWithoutAutoMigrate(db *gorm.DB) (*Adapter, error) {
+	ctx := db.Statement.Context
+	if ctx == nil {
+		ctx = context.Background()
+	}
+
+	ctx = context.WithValue(ctx, disableMigrateKey, false)
+
+	return NewAdapterByDBUseTableName(db.WithContext(ctx), "", defaultTableName)
+}
+
 func NewAdapterByDBWithCustomTable(db *gorm.DB, t interface{}, tableName ...string) (*Adapter, error) {
 	ctx := db.Statement.Context
 	if ctx == nil {

adapter_test.go

@@ -192,6 +192,30 @@ func initAdapterWithGormInstanceByName(t *testing.T, db *gorm.DB, name string) *
 	return a
 }
 
+func initAdapterWithoutAutoMigrate(t *testing.T, db *gorm.DB) *Adapter {
+	var err error
+	hasTable := db.Migrator().HasTable(defaultTableName)
+	if hasTable {
+		err = db.Migrator().DropTable(defaultTableName)
+		if err != nil {
+			panic(err)
+		}
+	}
+
+	a, err := NewAdapterWithoutAutoMigrate(db)
+
+	hasTable = a.db.Migrator().HasTable(a.getFullTableName())
+	if hasTable {
+		t.Fatal("AutoMigration has been disabled but tables are still created in NewAdapterWithoutAutoMigrate method")
+	}
+	err = a.db.Migrator().CreateTable(&CasbinRule{})
+	if err != nil {
+		panic(err)
+	}
+	initPolicy(t, a)
+	return a
+}
+
 func initAdapterWithGormInstanceByMulDb(t *testing.T, dbPool DbPool, dbName string, prefix string, tableName string) *Adapter {
 	//Create an Adapter
 	a, _ := NewAdapterByMulDb(dbPool, dbName, prefix, tableName)
@@ -354,6 +378,44 @@ func TestAdapterWithCustomTable(t *testing.T) {
 	testFilteredPolicy(t, a)
 }
 
+func TestAdapterWithoutAutoMigrate(t *testing.T) {
+	db, err := gorm.Open(mysql.Open("root:@tcp(127.0.0.1:3306)/casbin"), &gorm.Config{})
+	if err != nil {
+		panic(err)
+	}
+
+	a := initAdapterWithoutAutoMigrate(t, db)
+	testAutoSave(t, a)
+	testSaveLoad(t, a)
+
+	a = initAdapterWithoutAutoMigrate(t, db)
+	testFilteredPolicy(t, a)
+
+	db, err = gorm.Open(postgres.Open("user=postgres password=postgres host=127.0.0.1 port=5432 sslmode=disable"), &gorm.Config{})
+	if err != nil {
+		panic(err)
+	}
+
+	if err = db.Exec("CREATE DATABASE casbin_custom_table").Error; err != nil {
+		// 42P04 is	duplicate_database
+		if !strings.Contains(fmt.Sprintf("%s", err), "42P04") {
+			panic(err)
+		}
+	}
+
+	db, err = gorm.Open(postgres.Open("user=postgres password=postgres host=127.0.0.1 port=5432 sslmode=disable dbname=casbin_custom_table"), &gorm.Config{})
+	if err != nil {
+		panic(err)
+	}
+
+	a = initAdapterWithoutAutoMigrate(t, db)
+	testAutoSave(t, a)
+	testSaveLoad(t, a)
+
+	a = initAdapterWithoutAutoMigrate(t, db)
+	testFilteredPolicy(t, a)
+}
+
 func TestAdapterWithMulDb(t *testing.T) {
 	//create new database
 	NewAdapter("mysql", "root:@tcp(127.0.0.1:3306)/", "casbin")