sqlc transaction wrapper that keeps call sites clean

13158 views

                  package store

import (
  "context"
  "database/sql"
)

type Querier interface {
  WithTx(tx *sql.Tx) Querier
  // ... add the methods you actually use
}

func InTx(ctx context.Context, db *sql.DB, q Querier, fn func(context.Context, Querier) error) error {
  tx, err := db.BeginTx(ctx, &sql.TxOptions{Isolation: sql.LevelReadCommitted})
  if err != nil {
    return err
  }
  defer tx.Rollback()

  if err := fn(ctx, q.WithTx(tx)); err != nil {
    return err
  }
  return tx.Commit()
}

When using sqlc, the generated query set usually has a WithTx method. I wrap that pattern so business logic can depend on an interface and still run inside a transaction. The key is to keep transaction boundaries explicit while avoiding passing *sql.Tx everywhere. The helper below begins a transaction, creates a transaction-bound querier via WithTx, runs the function, and commits on success. defer tx.Rollback() is the boring safety net that prevents leaked transactions on early returns. In production, I also set an isolation level via sql.TxOptions and I ensure ctx has a deadline so transactions don’t sit open. This is a small abstraction, but it keeps service methods tidy and makes unit testing easier because you can mock the interface.

Leah Thompson

More from Leah Thompson

sqlc transaction wrapper that keeps call sites clean

0 Comments

More from Leah Thompson