示例#1
0
// pgConnect: Open the Postgres database.  Returns any error
// encountered during the open.
func pgConnect() (string, error) {
	cfg, err := pgx.ParseURI(pgUrl)
	if err != nil {
		err = fmt.Errorf("Parse failure on Postgres URI %q: %v", pgUrl, err)
		return "", err
	}
	conn, err := pgx.Connect(cfg)
	if err != nil {
		err = fmt.Errorf("Couldn't connect to db at %q: %v", pgUrl, err)
		return "", err
	}
	pgConn = conn
	return pgUrl, nil
}
示例#2
0
// apply dataFunctions to the database.  Each is applied in a
// separate transaction, so later ones can rely on the effect of
// earlier ones having been committed.
func applyFunctions(fns []dataFunction) error {
	url := os.Getenv("DATABASE_URL")
	if url == "" {
		url = "postgres://localhost/susen?sslmode=disable"
	}

	// open the database, defer the close
	cfg, err := pgx.ParseURI(url)
	if err != nil {
		return err
	}
	conn, err := pgx.Connect(cfg)
	if err != nil {
		return err
	}
	defer conn.Close()

	// helper that runs each function inside a transaction, and
	// ensures that any problems are rolled back.
	runFunc := func(fn dataFunction) error {
		tx, err := conn.Begin()
		if err != nil {
			return err
		}
		defer func() {
			if e := recover(); e != nil {
				tx.Rollback()
				panic(e)
			}
		}()
		if err := fn(tx); err != nil {
			tx.Rollback()
			return err
		}
		return tx.Commit()
	}

	// run the functions
	for _, fn := range fns {
		if err := runFunc(fn); err != nil {
			return fmt.Errorf("%v failed: %v", fn, err)
		}
	}
	return nil
}