txdb

README

Single transaction based sql.Driver for GO

Package txdb is a single transaction based database sql driver. When the connection is opened, it starts a transaction and all operations performed on this sql.DB will be within that transaction. If concurrent actions are performed, the lock is acquired and connection is always released the statements and rows are not holding the connection.

Why is it useful. A very basic use case would be if you want to make functional tests you can prepare a test database and within each test you do not have to reload a database. All tests are isolated within transaction and though, performs fast. And you do not have to interface your sql.DB reference in your code, txdb is like a standard sql.Driver.

This driver supports any sql.Driver connection to be opened. You can register txdb for different sql drivers and have it under different driver names. Under the hood whenever a txdb driver is opened, it attempts to open a real connection and starts transaction. When close is called, it rollbacks transaction leaving your prepared test database in the same state as before.

Given, you have a mysql database called txdb_test and a table users with a username column.

    package main

    import (
        "database/sql"
        "log"

        "github.com/DATA-DOG/go-txdb"
        _ "github.com/go-sql-driver/mysql"
    )

    func init() {
        // we register an sql driver named "txdb"
        txdb.Register("txdb", "mysql", "root@/txdb_test")
    }

    func main() {
        // dsn serves as an unique identifier for connection pool
        db, err := sql.Open("txdb", "identifier")
        if err != nil {
            log.Fatal(err)
        }
        defer db.Close()

        if _, err := db.Exec(`INSERT INTO users(username) VALUES("gopher")`); err != nil {
            log.Fatal(err)
        }
    }

Every time you will run this application, it will remain in the same state as before.

Testing

Usage is mainly intended for testing purposes. See the db_test.go as an example. In order to run tests, you will need docker and docker-compose:

docker-compose up
make test

The tests are currently using postgres and mysql databases

Documentation

See godoc for general API details. See .travis.yml for supported go versions.

Contributions

Feel free to open a pull request. Note, if you wish to contribute an extension to public (exported methods or types) - please open an issue before to discuss whether these changes can be accepted. All backward incompatible changes are and will be treated cautiously.

The public API is locked since it is an sql.Driver and will not change.

License

txdb is licensed under the three clause BSD license

Documentation

Overview

Package txdb is a single transaction based database sql driver. When the connection is opened, it starts a transaction and all operations performed on this *sql.DB will be within that transaction. If concurrent actions are performed, the lock is acquired and connection is always released the statements and rows are not holding the connection.

Why is it useful. A very basic use case would be if you want to make functional tests you can prepare a test database and within each test you do not have to reload a database. All tests are isolated within transaction and though, performs fast. And you do not have to interface your sql.DB reference in your code, txdb is like a standard sql.Driver.

This driver supports any sql.Driver connection to be opened. You can register txdb for different sql drivers and have it under different driver names. Under the hood whenever a txdb driver is opened, it attempts to open a real connection and starts transaction. When close is called, it rollbacks transaction leaving your prepared test database in the same state as before.

Given, you have a mysql database called txdb_test and a table users with a username column.

Example:

	package main

	import (
		"database/sql"
		"log"

		"github.com/DATA-DOG/go-txdb"
		_ "github.com/go-sql-driver/mysql"
	)

	func init() {
		// we register an sql driver named "txdb"
		txdb.Register("txdb", "mysql", "root@/txdb_test")
	}

	func main() {
        // dsn serves as an unique identifier for connection pool
		db, err := sql.Open("txdb", "identifier")
		if err != nil {
			log.Fatal(err)
		}
		defer db.Close()

		if _, err := db.Exec(`INSERT INTO users(username) VALUES("gopher")`); err != nil {
			log.Fatal(err)
		}
	}

Every time you will run this application, it will remain in the same state as before.

Index

• func Register(name, drv, dsn string, options ...func(*conn) error)
• func SavePointOption(savePoint SavePoint) func(*conn) error
• type SavePoint

Functions

func Register

func Register(name, drv, dsn string, options ...func(*conn) error)

Register a txdb sql driver under the given sql driver name which can be used to open a single transaction based database connection.

When Open is called any number of times it returns the same transaction connection.

Any Begin, Commit calls will not start or close the transaction. Instead the savepoint will be created, released or rolled back. In case if your SQL driver does not support save points - use nil for the SavePointOption argument. If driver has non default save point logic, you can override the default with SavePointOption.

When Close is called, the transaction is rolled back.

Use drv (Driver) and dsn (DataSourceName) as the standard sql properties for your test database connection to be isolated within transaction.

The drv and dsn are the same items passed into `sql.Open(drv, dsn)`.

Note: if you open a secondary database, make sure to differianciate the dsn string when opening the sql.DB. The transaction will be isolated within that dsn

func SavePointOption

func SavePointOption(savePoint SavePoint) func(*conn) error

SavePointOption allows to modify the logic for transaction save points. In such cases if your driver does not support it, use nil. If not compatible with default use custom.

Types

type SavePoint

type SavePoint interface {
	Create(id string) string
	Release(id string) string
	Rollback(id string) string
}

SavePoint defines the syntax to create savepoints within transaction