🤖 db

amadan.net/rastrillo/rastrillo/db

Opens your SQLite database the way a CARLOS app needs it, as one *gorm.DB. It is a small package, and almost all its value is in what Open gets right. Data is the guide.

Open

func Open(path string, log *slog.Logger) (*DB, error)

Opens one file as two pools and returns a handle wrapping both. A nil logger defaults to slog.Default().

What it sets for you, and why each one is there:

• DSN pragma order. busy_timeout before journal_mode=WAL; the other order crashes under concurrent open. foreign_keys(1) is on.
• One writer connection. SQLite allows one writer, and queueing inside the pool beats getting SQLITE_BUSY at the call site.
• Several reader connections — runtime.NumCPU(), floor of four. WAL supports many readers, and serialising them behind one connection turns an open *sql.Rows plus any second query into a silent deadlock.
• dbresolver routing, so your code never picks a pool.
• An eager ping on both pools, so the file exists on disk from boot. That keeps hibernation replication happy.
• TranslateError: true, so errors.Is(err, gorm.ErrDuplicatedKey) works. Without the flag GORM never calls the dialector's Translate.
• UTC times.
• A GORM logger writing into your *slog.Logger, at warn level, with a 200ms slow-query threshold and ErrRecordNotFound ignored — a scoped by-id miss is the ordinary 404 path and happens on every not-yours URL.

DB

type DB struct {
	G *gorm.DB
}

G is the handle your models and handlers use. The two *sql.DB pools behind it are unexported.

DB.Writer

func (d *DB) Writer() *sql.DB

The write pool — one connection. migrate.Apply takes it directly rather than through the resolver, because it pins a single connection for a whole run: PRAGMA foreign_keys is per-connection state, and SQLite's twelve-step table rebuild has to toggle it outside the transaction.

d.G.DB() gets you the same pool through GORM, and is what most code uses when handing a *sql.DB to a database/sql package like sessions.

DB.Close

func (d *DB) Close() error

Closes both pools. It returns the writer's error in preference to the reader's, so a single returned error names the pool whose failure matters.

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