Code reviewHardcr-g538

Subject Code reviewLevel Senior–Staff~20 minCommon in Distributed systems interviewsIndustries Software development, Technology

Question

Review this read-through / write-through cache wrapper around a user store.

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.

Learn the concepts

Talk through your review

Code to reviewpython

1def get_user(uid):2    u = cache.get(uid)3    if u is None:4        u = db.fetch_user(uid)5        cache.set(uid, u, ttl=3600)6    return u7 8def update_user(uid, **fields):9    db.update_user(uid, **fields)10    cache.set(uid, db.fetch_user(uid), ttl=3600)

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