fix(redis_cache): apply namespace prefix in delete_cache and async_delete_cache

[elluvium]

Summary

• async_delete_cache and delete_cache in litellm/caching/redis_cache.py were not calling check_and_fix_namespace() before issuing the Redis DEL command
• When a namespace is configured, SET and GET correctly prefix the key (e.g. litellm.caching.caching:cronjob_lock:db_spend_update_job), but DEL targeted the raw key — which does not exist — so it always returned 0
• This caused PodLockManager to never explicitly release locks; every lock expired by TTL instead, producing a failed to release Redis lock warning on every batch-write cycle for every pod

Changes

• litellm/caching/redis_cache.py: add key = self.check_and_fix_namespace(key=key) to both async_delete_cache and delete_cache, matching the pattern used in every other cache method
• tests/test_litellm/caching/test_redis_cache.py: add test_delete_cache_applies_namespace — parametrized over namespace=None and namespace="myns" — asserting the correct key is passed to redis_client.delete in both the async and sync paths

Test plan

• uv run pytest tests/test_litellm/caching/test_redis_cache.py -v — all 26 tests pass
• uv run ruff check litellm/caching/redis_cache.py tests/test_litellm/caching/test_redis_cache.py — clean
• uv run mypy litellm/caching/redis_cache.py --ignore-missing-imports — no issues

[CLAassistant]

All committers have signed the CLA.

[greptile-apps]

Greptile Summary

This PR fixes a namespace prefix bug in RedisCache where delete_cache and async_delete_cache were issuing DEL against raw keys while SET/GET used namespaced keys, causing lock releases to always miss and fall back to TTL expiry. The fix adds the single missing check_and_fix_namespace call to both methods, exactly mirroring the pattern used in every other cache operation.

Confidence Score: 5/5

Safe to merge — minimal, targeted fix with proper test coverage and no regressions.

The change is a one-liner applied to two methods, consistent with the established pattern in all other cache operations. Tests cover both the namespace=None and namespace="myns" cases for both code paths using mocks only. No logic is altered elsewhere.

No files require special attention.

Important Files Changed

Filename	Overview
litellm/caching/redis_cache.py	Adds check_and_fix_namespace call to async_delete_cache and delete_cache, matching the existing pattern used in every other cache method; also adds type annotation to delete_cache.
tests/test_litellm/caching/test_redis_cache.py	Adds test_delete_cache_applies_namespace parametrized over None/"myns" covering both async and sync delete paths with mocks; also removes unused fastapi.testclient.TestClient import.

_{Reviews (1): Last reviewed commit: "fix(redis_cache): apply namespace in del..." | Re-trigger Greptile}

[codspeed-hq]

Merging this PR will not alter performance

✅ 16 untouched benchmarks

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_{Comparing elluvium:fix/redis-namespace-delete (62473fc) with main (3e1479c)}

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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[oss-pr-review-agent-shin]

🤖 litellm-agent: Auto-merge skipped — the staging branch shin_agent_oss_staging_05_18_2026 has 1279 commit(s) not in your branch. Merging as-is would produce a confusing diff on the staging PR.

Please rebase your branch onto shin_agent_oss_staging_05_18_2026 and push; the agent will re-review automatically.

[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.