Concurrent map modification during iteration
Review this Go code that removes expired sessions from a map while iterating.
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 18 min
Mark a line and say what kind of problem it is.0 findings
1func reap(sessions map[string]Session, now time.Time) int {
2 removed := 0
3 for id, s := range sessions {
4 if s.expiresAt.Before(now) {
5 delete(sessions, id)
6 removed++
7 }
8 if s.lastSeen.Add(idleTTL).Before(now) {
9 sessions[id] = touch(s) // refresh non-expired idle ones
10 }
11 }
12 return removed
13}
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