Couchbase SDK Patterns — Python

Production patterns for KV operations in Python: concurrency control, bulk operations, error handling, and retry logic.

CAS — Optimistic Locking

CAS (Compare And Swap) prevents lost writes when multiple clients update the same document concurrently. Every mutation returns a new CAS value; supply it on the next write — the server rejects it if another client modified the document in between.

from couchbase.exceptions import CasMismatchException
from couchbase.options import ReplaceOptions