txmanager

txmanager

The txnmanager package is a nested transation manager for database/sql.

SYNOPSIS

Use TxBegin to start a transaction, and TxCommit or TxRollback to finish the transaction.

import (
	"database/sql"

	"github.com/shogo82148/txmanager"
)

func Example(db *sql.DB) {
	dbm := txmanager.NewDB(db)

	// start a transaction
	tx, _ := dbm.TxBegin()
	defer tx.TxFinish()

	// Exec INSERT in a transaction
	_, err := tx.Exec("INSERT INTO t1 (id) VALUES(1)")
	if err != nil {
		tx.TxRollback()
	}
	tx.TxCommit()
}

You can manage txmanager.DB with txmanager.Do.

import (
	"database/sql"

	"github.com/shogo82148/txmanager"
)

func Example(db *sql.DB) {
	dbm := txmanager.NewDB(db)
	txmanager.Do(dbm, func(tx txmanager.Tx) error {
		// Exec INSERT in a transaction
		_, err := tx.Exec("INSERT INTO t1 (id) VALUES(1)")
		return err
	})
}

NESTED TRANSACTION

import (
	"database/sql"

	"github.com/shogo82148/txmanager"
)

func Foo(dbm *txmanager.DB) error {
	return txmanager.Do(dbm, func(tx txmanager.Tx) error {
		_, err := tx.Exec("INSERT INTO t1 (id) VALUES(1)")
		return err
	})
}

func Example(db *sql.DB) {
	dbm := txmanager.NewDB(db)

	Foo(dbm)

	txmanager.Do(dbm, func(tx txmanager.Tx) error {
		return Foo(tx)
	})
}

END HOOK

TxCommit necessarily does not do COMMIT SQL statemant. So following code sometimes outputs wrong log.

func Foo(dbm *txmanager.DB) error {
	err := txmanager.Do(dbm, func(tx txmanager.Tx) error {
		_, err := tx.Exec("INSERT INTO t1 (id) VALUES(1)"); err != nil {
		return err
	})
	if err != nil {
		return err
	}

	// TxCommit is success, while the transaction might fail
	log.Println("COMMIT is success!!!")
	return nil
}

Use TxAddEndHook to avoid it. It is inspired by DBIx::TransactionManager::EndHook.

func Foo(dbm *txmanager.DB) error {
	return txmanager.Do(dbm, func(tx txmanager.Tx) error {
		if _, err := tx.Exec("INSERT INTO t1 (id) VALUES(1)"); err != nil {
			return err
		}
		tx.TxAddEndHook(func() error {
			// It is called if all transactions are executed successfully.
			log.Println("COMMIT is success!!!")
		})
		return nil
	})
}

LICENSE

This software is released under the MIT License, see LICENSE.txt.

godoc

See godoc for more imformation.