Go transaction manager

Transaction manager is an abstraction to coordinate database transaction boundaries.

Easiest way to get the perfect repository.

Supported implementations

• database/sql, docs ( Go 1.13)
• jmoiron/sqlx, docs ( Go 1.13)
• gorm, docs ( Go 1.18)
• mongo-go-driver, docs ( Go 1.13)
• go-redis/redis, docs ( Go 1.17)
• pgx_v4, docs ( Go 1.16)
• pgx_v5, docs ( Go 1.19)

Installation

go get github.com/avito-tech/go-transaction-manager/trm/v2

To install some support database use

.

For example

.

Backwards Compatibility

The library is compatible with the most recent two versions of Go. Compatibility beyond that is not guaranteed.

The critical bugs are firstly solved for the most recent two Golang versions and then for older ones if it is simple.

Disclaimer: Keep your dependencies up to date, even indirect ones.

helps you.

Note: The go-transaction-manager uses some old dependencies to support backwards compatibility for old versions of Go.

Usage

To use multiple transactions from different databases, you need to set CtxKey in Settings by WithCtxKey (docs).

For nested transactions with different transaction managers, you need to use ChainedMW (docs).

To skip a transaction rollback due to an error, use ErrSkip or Skippable

Explanation of the approach English, Russian article and youtube.

Examples with an ideal repository and nested transactions.

• database/sql
• jmoiron/sqlx
• gorm
• mongo-go-driver
• go-redis/redis
• pgx_v4
• pgx_v5

Below is an example how to start usage.

package main

import (
	"context"
	"fmt"

	"github.com/jmoiron/sqlx"
	_ "github.com/mattn/go-sqlite3"

	trmsqlx "github.com/avito-tech/go-transaction-manager/drivers/sqlx/v2"
	"github.com/avito-tech/go-transaction-manager/trm/v2/manager"
)

func main() {
	db, err := sqlx.Open("sqlite3", "file:test?mode=memory")
	checkErr(err)
	defer db.Close()

	sqlStmt := `CREATE TABLE IF NOT EXISTS user (user_id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT, username TEXT);`
	_, err = db.Exec(sqlStmt)
	checkErr(err, sqlStmt)

	r := newRepo(db, trmsqlx.DefaultCtxGetter)
	ctx := context.Background()
	trManager := manager.Must(trmsqlx.NewDefaultFactory(db))
	u := &user{Username: "username"}

	err = trManager.Do(ctx, func(ctx context.Context) error {
		checkErr(r.Save(ctx, u))

		// example of nested transactions
		return trManager.Do(ctx, func(ctx context.Context) error {
			u.Username = "new_username"
			return r.Save(ctx, u)
		})
	})
	checkErr(err)

	userFromDB, err := r.GetByID(ctx, u.ID)
	checkErr(err)

	fmt.Println(userFromDB)
}

func checkErr(err error, args ...interface{}) {
	if err != nil {
		panic(fmt.Sprint(append([]interface{}{err}, args...)...))
	}
}

type repo struct {
	db     *sqlx.DB
	getter *trmsqlx.CtxGetter
}

func newRepo(db *sqlx.DB, c *trmsqlx.CtxGetter) *repo {
	return &repo{db: db, getter: c}
}

type user struct {
	ID       int64  `db:"user_id"`
	Username string `db:"username"`
}

func (r *repo) GetByID(ctx context.Context, id int64) (*user, error) {
	query := "SELECT * FROM user WHERE user_id = ?;"
	u := user{}

	return &u, r.getter.DefaultTrOrDB(ctx, r.db).GetContext(ctx, &u, r.db.Rebind(query), id)
}

func (r *repo) Save(ctx context.Context, u *user) error {
	query := `UPDATE user SET username = :username WHERE user_id = :user_id;`
	if u.ID == 0 {
		query = `INSERT INTO user (username) VALUES (:username);`
	}

	res, err := sqlx.NamedExecContext(ctx, r.getter.DefaultTrOrDB(ctx, r.db), r.db.Rebind(query), u)
	if err != nil {
		return err
	} else if u.ID != 0 {
		return nil
	} else if u.ID, err = res.LastInsertId(); err != nil {
		return err
	}

	return err
}

Benchmark

Comparing examples with and without trm.

Contribution

Requirements

• golangci-lint
• make

Local Running

• To install all dependencies use
  make go.mod.tidy
  or
  make go.mod.vendor
  .
• To run all tests use
  make test
  or
  make test.with_real_db
  for integration tests.

To run database by docker, there is docker-compose.yaml.

docker compose -f trm/drivers/test/docker-compose.yaml up

For full GitHub Actions run, you can use act.

Running old go versions

To stop Golang upgrading set environment variable

.

go install go1.16 # or older version
go1.16 install

Use

to prevent

go.mod

modification.

To run tests

go1.16 test -race -mod=readonly ./...

How to bump up Golang version in CI/CD

1. Changes in .github/workflows/main.yaml.
   1. Add all old version of Go in
      go-version:
      for
      tests-units
      job.
   2. Update
      go-version:
      on current version of Go for
      lint
      and
      tests-integration
      jobs.
2. Update build tags by replacing
   build go1.xx
   on new version.

Resolve problems with old version of dependencies

To build

compatible for old version use

go mod tidy -compat=1.13

(docs).

However,

doesn't always work correct and we need to set some library versions manually.

1. go get go.uber.org/multierr@v1.9.0
   in trm, sql, sqlx.
2. go get github.com/mattn/go-sqlite3@v1.14.14
   in trm, sql, sqlx.
3. go get github.com/stretchr/testify@v1.8.2
   in trm, sql, sqlx, goredis8, mongo.
4. go get github.com/jackc/pgconn@v1.14.2
   in pgxv4. Golang version was bumped up from 1.12 to 1.17 in pgconn v1.14.3.
5. go get golang.org/x/text@v0.13.0
   in pgxv4.