feat: harden the Redis connection for distributed runs - #24
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SpecBandit's Redis is a best-effort coordinator for a distributed run, but CI runners can sit a WAN hop away from it (e.g. a cross-datacenter Kilo mesh). A transient blip was reddening backend-spec shards with `[specbandit] Redis error: ... (Redis::TimeoutError)` even though the Redis server was healthy — the connect just timed out over the inter-DC tunnel. - Explicit client resilience: pass connect/read/write timeouts and reconnect_attempts to `Redis.new` instead of relying on library defaults. - Larger, configurable retry budget: MAX_ATTEMPTS default raised 3 -> 5 and made env/flag-driven (SPECBANDIT_REDIS_MAX_ATTEMPTS / --redis-max-attempts), with capped (10s) exponential backoff so short blips are ridden out. Bumps the gem to 1.1.0.
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Why
Backend-spec shards in
factorialco/factorialCI intermittently fail with:The Redis server is healthy — it's a network-path problem. SpecBandit's shared Redis is pinned to one node in one datacenter (Kilo location
hel), and ~1/3 ofbuild-lrunners now live in a different DC (fsn1, added 2026-07-01) and reach Redis over an inter-DC WireGuard tunnel (~29 ms vs ~5 ms intra-DC). A transient blip on that tunnel exhausts SpecBandit's short retry budget andworkexits 1, reddening the build.What
Harden the Redis connection so short blips are ridden out instead of failing the run:
redis_queue.rb):Redis.newnow getsconnect_timeout/read_timeout/write_timeout+reconnect_attemptsinstead of bare library defaults.configuration.rb,redis_queue.rb):MAX_ATTEMPTSdefault 3 → 5, env/flag-driven (SPECBANDIT_REDIS_MAX_ATTEMPTS/--redis-max-attempts), with capped (10s) exponential backoff.No behavioural change when Redis is reachable; on a hard outage
workstill fails loudly as before (never a silent pass).Notes for review
specbanditjskeeps the two implementations in sync.Tests
bundle exec rspec spec/specbandit spec/integration→ 126 examples, 0 failures (integration pending only without a local Redis). Added connection-option, env-config, and configurable-retry (incl. custommax_attempts) coverage inredis_queue_spec.rb/configuration_spec.rb.Draft for review.