fix: 🐛 Session budget shutdown and TTL fixes

[evaline-ju]

Summary

Address two comments flagged as 'out of scope' in #777 but affecting the original plugin, with test updates:

• TTL leak (accumulate): moved Expire out of the gate so it runs every call; Redis EXPIRE is idempotent, so this self-heals prior failures.
• Shutdown double-close panic: guarded with sync.Once

Assisted-By: Claude (Anthropic AI) noreply@anthropic.com

Related issue(s)

Closes: #801

Summary by CodeRabbit

Summary by CodeRabbit

• Bug Fixes
  • Improved session budget reliability by refreshing Redis-backed session expiration during ongoing activity.
  • Added recovery when expiration updates temporarily fail, helping prevent sessions from persisting longer than intended.
  • Made session shutdown safe to call repeatedly and ensured cleanup occurs only once.
• Tests
  • Added coverage for expiration recovery after transient failures.
  • Added coverage confirming repeated shutdown calls complete safely.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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Configuration used: defaults

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📥 Commits

Reviewing files that changed from the base of the PR and between 762773d and e42dd79.

📒 Files selected for processing (2)

• authbridge/authlib/plugins/sessionbudget/plugin.go
• authbridge/authlib/plugins/sessionbudget/plugin_test.go

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📝 Walkthrough

Walkthrough

The session budget plugin now refreshes Redis TTLs after every accumulation, logs storage failures, and supports repeated shutdown calls safely. Regression tests cover TTL recovery and repeated shutdown. Dependabot now checks the Redis storage module weekly.

Changes

Session budget reliability

Layer / File(s)	Summary
Redis TTL recovery authbridge/authlib/plugins/sessionbudget/plugin.go, authbridge/authlib/plugins/sessionbudget/plugin_test.go	Redis accumulation refreshes the session key TTL on every call and logs HashSetNX and Expire failures. Tests verify TTL recovery after a failed expiration.
Idempotent shutdown authbridge/authlib/plugins/sessionbudget/plugin.go, authbridge/authlib/plugins/sessionbudget/plugin_test.go	SessionBudget.Shutdown uses sync.Once for shutdown signaling and store closure. Tests verify repeated shutdown and exactly-once store closure.

Redis Dependabot configuration

Layer / File(s)	Summary
Redis module update entry .github/dependabot.yml	Dependabot now checks Go modules in /authbridge/storage/redis weekly.

Estimated code review effort: 2 (Simple) | ~10 minutes

Merge Risk: 🟠 High · up to e42dd

Repeated session shutdowns can still close storage more than once and trigger a panic, creating an availability risk. The PR is not merge-ready until shutdown is made safely idempotent or the risk is explicitly accepted.

Suggested reviewers: abigailgold

🚥 Pre-merge checks | ✅ 3 | ❌ 2

❌ Failed checks (2 warnings)

Check name	Status	Explanation	Resolution
Out of Scope Changes check	⚠️ Warning	The Dependabot configuration change is unrelated to the linked session-budget shutdown and TTL fixes.	Remove the unrelated Dependabot configuration change or move it to a separate pull request.
Docstring Coverage	⚠️ Warning	Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 6 functions across 2 files.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly summarizes the session-budget shutdown and TTL fixes implemented in the pull request.
Linked Issues check	✅ Passed	The changes address both linked issue objectives: idempotent shutdown and self-healing Redis session TTL refresh.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[coderabbitai]

Actionable comments posted: 1

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Inline comments:
In `@authbridge/authlib/plugins/sessionbudget/plugin.go`:
- Around line 201-203: Update SessionBudget.Shutdown to guard p.store.Close()
with a separate sync.Once and retain/return its error consistently across calls,
while keeping shutdownOnce for p.stopCh. Adjust TestShutdown_DoubleCloseSafe to
use a non-canceled context and verify that two successful shutdowns close the
store exactly once.

🪄 Autofix

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• Push a commit to this branch (recommended)
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ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: d7a0b67b-dd14-41cd-bbfb-e7047fa7f07b

📥 Commits

Reviewing files that changed from the base of the PR and between 60b684d and 762773d.

📒 Files selected for processing (3)

• .github/dependabot.yml
• authbridge/authlib/plugins/sessionbudget/plugin.go
• authbridge/authlib/plugins/sessionbudget/plugin_test.go

Included review availability: Your plan provides up to 1 included review per hour; 0 remain after this review.

[clawgenti]

Targeted fixes for two correctness issues flagged in #777: unconditional Expire self-heal on every accumulate call, and sync.Once-guarded Shutdown to prevent double-close panics. Both fixes are well-motivated with clear inline docs and direct test coverage.

• suggestion (plugin.go line 534): Expire is now called unconditionally on every accumulate invocation — correct for self-healing, but this adds a Redis round-trip per call even when the TTL is healthy. Worth benchmarking under load to confirm the overhead is acceptable, or consider a best-effort refresh (log-and-continue already handles errors correctly).
• nit (plugin_test.go line 324): p.store = spy bypasses Configure's store initialization by direct field assignment. This works but relies on unexported field access in tests — adding a test-only constructor or option would make this more resilient to future refactors.

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Reviewed by clawgenti using the github-pr-review skill

[evaline-ju]

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[pdettori]

Summary

Two out-of-scope issues from #777 are addressed cleanly, plus a dependabot entry for the new Redis storage backend. Both fixes are correct, use idiomatic sync.Once guards, and ship with assertive tests that verify the mechanism, not just the outcome. Previously-swallowed errors (HashSetNX, Expire) are now logged — a real improvement.

Verified during review:

• Shutdown double-close — shutdownOnce/closeOnce correctly prevent both the close(p.stopCh) panic and the non-idempotent store.Close() re-call. Concurrent-caller and post-timeout-retry paths both hold (sync.Once.Do provides the needed happens-before on closeErr). ✅
• TTL self-heal — moving Expire out of the if set gate makes it run every accumulate. Worth noting this is also a semantic improvement, not just self-heal: the TTL now slides with activity, so an active session's budget key no longer expires mid-session at started_at + TTL. Correct behavior for a budget, and the code comment documents the self-heal rationale well. ✅
• Tests — oneShotExpireFailStore (HashSetNX succeeds while Expire fails once) is the right tool; the existing controllableStore couldn't express this asymmetric failure. Both new tests are assertive with no hidden skips. ✅
• dependabot.yml — correct gomod entry for /authbridge/storage/redis. ✅

Author: evaline-ju (MEMBER — maintainer)
Areas reviewed: Go (plugin + tests), CI/dependabot
Agent/IDE config (.claude/.vscode): none
Commits: 4 commits, all signed-off: yes
CI status: passing (19/19; Spellcheck skipped)

Minor nit (non-blocking): commit subjects use emoji prefixes rather than the conventional-prefix style, but the verify-pr-title check passed.

LGTM. 🚀

Assisted-By: Claude Code