Enable multiple Erupe instances to share a single PostgreSQL database
without destroying each other's state, fix existing data races in
cross-channel access, and lay groundwork for future distributed
channel server deployments.
Phase 1 — DB safety:
- Scope DELETE FROM servers/sign_sessions to this instance's server IDs
- Fix ci++ bug where failed channel start shifted subsequent IDs
Phase 2 — Fix data races in cross-channel access:
- Lock sessions map in FindSessionByCharID and DisconnectUser
- Lock stagesLock in handleMsgSysLockGlobalSema
- Snapshot sessions/stages under lock in TransitMessage types 1-4
- Lock channel when finding mail notification targets
Phase 3 — ChannelRegistry interface:
- Define ChannelRegistry interface with 7 cross-channel operations
- Implement LocalChannelRegistry with proper locking
- Add SessionSnapshot/StageSnapshot immutable copy types
- Delegate WorldcastMHF, FindSessionByCharID, DisconnectUser to Registry
- Migrate LockGlobalSema and guild mail handlers to use Registry
- Add comprehensive tests including concurrent access
Phase 4 — Per-channel enable/disable:
- Add Enabled *bool to EntranceChannelInfo (nil defaults to true)
- Skip disabled channels in startup loop, preserving ID stability
- Add IsEnabled() helper with backward-compatible default
- Update config.example.json with Enabled field
Add explicit error discards (_ =) for Close() calls on network
connections, SQL rows, and file handles across 28 files. Also add
.golangci.yml with standard linter defaults to match CI configuration.
Re-enable the golangci-lint job in CI (disabled Oct 2025), update to
Go 1.25 and golangci-lint-action v7. Fix errcheck, gosimple S1009,
staticcheck SA4031 and SA2001 errors across 54 files. Remaining ~39
lint errors will be addressed in follow-up commits.