sync.Once error not propagated
Review this Go lazy-connection initializer.
What is the bug with this sync.Once usage?
What a strong answer looks like
Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix, specific and kind.
0:00 of about 40 min
Mark a line and say what kind of problem it is.0 findings
1type DB struct {
2 once sync.Once
3 conn *sql.DB
4}
5
6func (d *DB) Conn() (*sql.DB, error) {
7 var err error
8 d.once.Do(func() {
9 d.conn, err = sql.Open("postgres", dsn())
10 if err == nil {
11 err = d.conn.Ping() // verify connectivity
12 }
13 })
14 return d.conn, err
15}
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