Rene Nochebuena
d9d07bcb70
database/sql-backed MySQL client with launcher lifecycle, health check, unit-of-work via context injection, and structured error mapping. What's included: - Executor / Tx / Client / Component interfaces using database/sql native types (sql.Result, *sql.Rows, *sql.Row) - Tx.Commit() / Tx.Rollback() without ctx, matching the honest database/sql contract - New(logger, cfg) constructor; *sql.DB opened in OnInit - Config struct with env-tag support for all pool tuning parameters - UnitOfWork via context injection; GetExecutor(ctx) returns active *sql.Tx or *sql.DB - HandleError mapping MySQLError.Number to xerrors codes (1062 → AlreadyExists, 1216/1217/1451/1452 → InvalidInput, ErrNoRows → NotFound) - Driver imported as mysqldrv alias to avoid package name collision - health.Checkable at LevelCritical; HealthCheck delegates to db.PingContext Tested-via: todo-api POC integration Reviewed-against: docs/adr/
mysql
database/sql-backed MySQL client with launcher lifecycle and health check integration.
Install
go get code.nochebuena.dev/go/mysql
Usage
db := mysql.New(logger, cfg)
lc.Append(db)
r.Get("/health", health.NewHandler(logger, db))
Unit of Work
uow := mysql.NewUnitOfWork(logger, db)
err := uow.Do(ctx, func(ctx context.Context) error {
exec := db.GetExecutor(ctx) // returns the active Tx
_, err := exec.ExecContext(ctx, "INSERT INTO orders ...")
return err
})
Error mapping
if err := db.HandleError(err); err != nil { ... }
| MySQL error | xerrors code |
|---|---|
| 1062 (ER_DUP_ENTRY) | ErrAlreadyExists |
| 1216/1217/1451/1452 (foreign key) | ErrInvalidInput |
sql.ErrNoRows |
ErrNotFound |
| anything else | ErrInternal |
Configuration
| Env var | Default | Description |
|---|---|---|
MYSQL_HOST |
required | Database host |
MYSQL_PORT |
3306 |
Database port |
MYSQL_USER |
required | Username |
MYSQL_PASSWORD |
required | Password |
MYSQL_NAME |
required | Database name |
MYSQL_MAX_CONNS |
5 |
Max open connections |
MYSQL_MIN_CONNS |
2 |
Max idle connections |