Counter loses increments

Code reviewStorage & CDNConcurrencySenior–Staff~22 min

Review this Python counter persisted to a shared file.

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 22 min

Mark a line and say what kind of problem it is.0 findings

1import json, os

3COUNTER_FILE = "/var/lib/app/counter.json"

5def increment_counter():

6 if os.path.exists(COUNTER_FILE):

7 with open(COUNTER_FILE) as f:

8 state = json.load(f)

9 else:

10 state = {"count": 0}

11 state["count"] += 1

12 with open(COUNTER_FILE, "w") as f:

13 json.dump(state, f)

14 return state["count"]

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