Function update

core/metadata/bolt.go:47–55

update gets a writable bolt db transaction either from the context or starts a new one with the provided bolt database.

(ctx context.Context, db Transactor, fn func(*bolt.Tx) error)

// update gets a writable bolt db transaction either from the context
// or starts a new one with the provided bolt database.
func update(ctx context.Context, db Transactor, fn func(*bolt.Tx) error) error {
	tx, ok := boltutil.Transaction(ctx)
	if !ok {
		return db.Update(fn)
	} else if !tx.Writable() {
		return fmt.Errorf("unable to use transaction from context: %w", errbolt.ErrTxNotWritable)
	}
	return fn(tx)
}