When SlotNotCoveredError is raised, the cluster topology should be reinitialized as part of error handling and retrying of the commands. by petyaslavova · Pull Request #3621 · redis/redis-py (original) (raw)

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Description of change

Fixes issue #3620

When we are handling different errors, we run cluster reinitialization that calls CLUSTER SLOTS.
Sometimes the cluster slots temporarily might not be fully covered and if we try to execute a command against key from the missing slots we receive SlotNotCoveredError.
The problem is that after this error appears we don't try to reinitialize again the slots and the Cluster client can't heal itself.

With this change I'm adding error handling for the SlotNotCoveredError, the same way we handle ClusterDownErrors - try to extract the slots coverage after a little sleep.