Erupe/IMPROVEMENTS.md

Erupe Improvement Recommendations

This document outlines prioritized improvements identified through codebase analysis.

Critical Priority

1. Test Coverage

Current state: 7.5% coverage on core channelserver (12,351 lines of code)

Recommendations:

• Add tests for packet handlers - 400+ handlers with minimal coverage
• Focus on critical files:
  • server/channelserver/handlers_quest.go
  • server/channelserver/handlers_guild.go
  • server/channelserver/sys_session.go
  • server/channelserver/sys_stage.go
• Create table-driven tests for the handler table
• Add fuzzing tests for packet parsing in common/byteframe/
• Target: 40%+ coverage on channelserver

2. Update Dependencies

Outdated packages in go.mod with potential security implications:

Package	Current	Latest
go.uber.org/zap	1.18.1	1.27.0+
github.com/spf13/viper	1.8.1	1.18.0+
golang.org/x/crypto	0.1.0	latest
github.com/lib/pq	1.10.4	latest

Action:

go get -u ./...
go mod tidy
go test -v ./...

3. Add Context-Based Cancellation

server/channelserver/sys_session.go spawns goroutines without context.Context, preventing graceful shutdown and causing potential goroutine leaks.

Changes needed:

• Add context.Context to Session.Start()
• Pass context to sendLoop() and recvLoop()
• Implement cancellation on session close
• Add timeout contexts for database operations

---

Important Priority

4. Fix Error Handling

Issues found:

• 61 instances of panic() or Fatal() that crash the entire server
• Ignored errors in main.go lines 29, 32, 195-196:

  _ = db.MustExec("DELETE FROM guild_characters")  // Error ignored
  

• Typos in error messages (e.g., "netcate" instead of "netcafe" in handlers_cafe.go)

Action:

# Find all panics to review
grep -rn "panic(" server/

# Find ignored errors
grep -rn "_ = " server/ | grep -E "(Exec|Query)"

5. Refactor Large Files

Files exceeding maintainability guidelines:

File	Lines
handlers_guild.go	1,986
handlers.go	1,835
handlers_shop_gacha.go	679
handlers_house.go	589

Recommendations:

• Split large handler files by functionality
• Move massive hex strings in handlers_tactics.go and handlers_quest.go to separate data files or compressed format
• Extract repeated patterns into utility functions

6. Enhance CI/CD Pipeline

Current gaps:

• No code coverage threshold enforcement
• No security scanning
• No database migration testing

Add to .github/workflows/:

• Coverage threshold (fail build if coverage drops below 30%)
• gosec for security scanning
• Integration tests with test database
• go mod audit for vulnerability scanning (Go 1.22+)

---

Nice to Have

7. Logging Cleanup

Issues:

• 17 remaining fmt.Print/println calls should use zap
• handlers_cast_binary.go creates a new logger on every handler call (inefficient)

Action:

# Find printf calls that should use zap
grep -rn "fmt.Print" server/
grep -rn "println" server/

8. Configuration Improvements

Hardcoded values to extract:

Value	Location	Suggested Config Key
maxDecoMysets = 40	handlers_house.go	GameplayOptions.MaxDecoMysets
decoMysetSize = 78	handlers_house.go	GameplayOptions.DecoMysetSize
Session timeout (30s)	sys_session.go:132	Channel.SessionTimeout
Packet queue buffer (20)	sys_session.go	Channel.PacketQueueSize

Recommendation: Create config/constants.go for game constants or add to ErupeConfig.

9. Resolve Technical Debt

14 TODO/FIXME comments in core code:

File	Issue
signserver/session.go	Token expiration not implemented
handlers.go	Off-by-one error in log key index
handlers_guild.go	Multiple incomplete features
handlers_stage.go	Unknown packet behavior
crypto/crypto_test.go	Failing test case needs debugging

---

Quick Wins

Immediate Actions

# 1. Update dependencies
go get -u ./... && go mod tidy

# 2. Run security check
go install github.com/securego/gosec/v2/cmd/gosec@latest
gosec ./...

# 3. Find all panics
grep -rn "panic(" server/ --include="*.go"

# 4. Find ignored errors
grep -rn "_ = " server/ --include="*.go" | grep -v "_test.go"

# 5. Check for race conditions
go test -race ./...

# 6. Generate coverage report
go test ./... -coverprofile=coverage.out
go tool cover -html=coverage.out -o coverage.html

Low-Effort High-Impact

1. Fix error message typo in handlers_cafe.go ("netcate" -> "netcafe")
2. Add defer rows.Close() where missing after database queries
3. Replace fmt.Print calls with zap logger
4. Add missing error checks for db.Exec() calls

---

Metrics to Track

Metric	Current	Target
Test coverage (channelserver)	7.5%	40%+
Test coverage (overall)	21.4%	50%+
Panic/Fatal calls	61	0 (in handlers)
Ignored errors	~20	0
TODO/FIXME comments	14	0
Outdated dependencies	4+	0

---

Implementation Order

1. Week 1: Update dependencies, fix critical error handling
2. Week 2: Add context cancellation to session lifecycle
3. Week 3-4: Expand test coverage for core handlers
4. Week 5: Refactor large files, extract constants
5. Ongoing: Resolve TODO comments, improve documentation

---

Release Milestones (9.3.0)

The following milestones are organized for the upcoming 9.3.0 release.

Milestone 1: Security & Stability

Token Lifecycle Management

• Implement automatic token cleanup after inactivity (signserver/session.go:133)
• Add configurable token expiration time
• Add rate limiting on sign-in attempts
• Document security implications of DisableTokenCheck option

Graceful Error Handling

• Replace 9 panic() calls in handlers_guild_scout.go with proper error returns
• Replace panic() in handlers_tower.go:43 (GetOwnTowerLevelV3) with stub response
• Convert fatal errors to recoverable errors where possible

Database Connection Resilience

• Configure connection pooling in main.go:182:

  db.SetMaxOpenConns(25)
  db.SetMaxIdleConns(5)
  db.SetConnMaxLifetime(5 * time.Minute)
  db.SetConnMaxIdleTime(2 * time.Minute)
  

• Add connection health monitoring
• Implement reconnection logic on connection loss

---

Milestone 2: Database Performance

Add Missing Indexes

• CREATE INDEX idx_characters_user_id ON characters(user_id)
• CREATE INDEX idx_guild_characters_guild_id ON guild_characters(guild_id)
• CREATE INDEX idx_mail_sender_id ON mail(sender_id)
• CREATE INDEX idx_user_binary_character_id ON user_binary(character_id)
• CREATE INDEX idx_gacha_entries_gacha_id ON gacha_entries(gacha_id)
• CREATE INDEX idx_distribution_items_dist_id ON distribution_items(distribution_id)

Fix N+1 Query Patterns

• handlers_guild.go:1419-1444 - Batch alliance member queries into single UNION query
• signserver/dbutils.go:135-162 - Rewrite friend/guildmate queries as JOINs
• handlers_distitem.go:34-46 - Replace subquery with JOIN + GROUP BY
• handlers_cafe.go:29-88 - Combine 4 single-field queries into one

Implement Caching Layer

• Create server/channelserver/cache/cache.go with sync.RWMutex-protected maps
• Cache gacha shop data at server startup (handlers_shop_gacha.go:112)
• Cache normal shop items
• Add cache invalidation on admin updates
• Cache guild information during session lifetime

---

Milestone 3: Feature Completeness

Guild System

• Implement daily RP reset (handlers_guild.go:740)
• Enable guild alliance applications (handlers_guild.go:1281)
• Add guild message board cleanup (handlers_guild.go:1888)
• Record guild user counts to database (handlers_guild.go:1946)
• Implement monthly reward tracker (handlers_guild.go:1967)
• Handle alliance application deletion (handlers_guild_alliance.go:154)

Daily/Recurring Systems

• Implement gacha daily reset at noon (handlers_shop_gacha.go:513)
• Add achievement rank notifications (handlers_achievement.go:122)

Daily Mission System (currently empty handlers)

• Implement handleMsgMhfGetDailyMissionMaster()
• Implement handleMsgMhfGetDailyMissionPersonal()
• Implement handleMsgMhfSetDailyMissionPersonal()

Tournament System (handlers_tournament.go)

• Implement handleMsgMhfEntryTournament() (line 58)
• Implement handleMsgMhfAcquireTournament() (line 60)
• Complete tournament info handler with real data (line 14-25)

Tower System (handlers_tower.go)

• Fix GetOwnTowerLevelV3 panic (line 43)
• Handle tenrou/irai hex decode errors gracefully (line 75)

Seibattle System

• Implement handleMsgMhfGetSeibattle() (handlers.go:1708-1711)
• Implement handleMsgMhfPostSeibattle()
• Add configuration toggle for Seibattle feature

---

Milestone 4: Operational Excellence

Health Checks & Monitoring

• Add /health HTTP endpoint for container orchestration
• Add /ready readiness probe
• Add /live liveness probe
• Implement basic Prometheus metrics:
  • erupe_active_sessions gauge
  • erupe_active_stages gauge
  • erupe_packet_processed_total counter
  • erupe_db_query_duration_seconds histogram

Logging Improvements

• Replace all fmt.Print/println calls with zap (17 instances)
• Fix logger creation in handlers_cast_binary.go (create once, reuse)
• Add correlation IDs for request tracing
• Add structured context fields (player ID, stage ID, guild ID)

Configuration Management

• Create config/constants.go for game constants
• Make session timeout configurable
• Make packet queue buffer size configurable
• Add feature flags for incomplete systems (Tournament, Seibattle)

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Milestone 5: Discord Bot Enhancements

Current state: Output-only with minimal features

New Features

• Player login/logout notifications
• Quest completion announcements
• Achievement unlock notifications
• Guild activity feed (joins, leaves, rank changes)
• Administrative commands:
  • /status - Server status
  • /players - Online player count
  • /kick - Kick player (admin only)
  • /announce - Server-wide announcement
• Two-way chat bridge (Discord ↔ in-game)

---

Milestone 6: Multi-Version Support

Client Version Handling

• Audit handlers for missing client version checks
• Document version-specific packet format differences
• Create version compatibility matrix
• Add version-specific tower system handling
• Test S6.0 through ZZ compatibility systematically

---

Milestone 7: Schema Management

Patch Schema Infrastructure

• Create numbered patch files in patch-schema/:
  • 01_add_indexes.sql - Performance indexes
  • 02_token_expiry.sql - Token cleanup support
  • 03_daily_mission.sql - Daily mission tables
• Add schema version tracking table
• Create migration runner script
• Document patch application process

Schema Cleanup

• Add PRIMARY KEY to shop_items_bought
• Add PRIMARY KEY to cafe_accepted
• Add foreign key constraints to child tables
• Remove or document unused tables (achievement, titles, feature_weapon)

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Milestone 8: Packet Implementation

High-Value Packets (393 files with "NOT IMPLEMENTED")

Priority implementations:

• msg_mhf_create_joint.go - Joint quest creation
• msg_mhf_mercenary_huntdata.go - Mercenary hunt data
• msg_mhf_save_deco_myset.go - Decoration preset saving
• msg_mhf_get_ud_ranking.go - User-defined quest rankings
• msg_mhf_load_hunter_navi.go - Hunter Navi system
• msg_mhf_answer_guild_scout.go - Guild scouting responses
• msg_mhf_acquire_guild_tresure.go - Guild treasure acquisition
• msg_mhf_payment_achievement.go - Payment achievements
• msg_mhf_stampcard_prize.go - Stamp card prizes

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Release Checklist

Before 9.3.0 release:

• All Milestone 1 items completed (Security & Stability)
• Critical database indexes added (Milestone 2)
• N+1 queries fixed (Milestone 2)
• Guild system TODOs resolved (Milestone 3)
• Health check endpoints added (Milestone 4)
• Schema patches created and tested (Milestone 7)
• Test coverage increased to 30%+
• All tests passing with race detector
• Dependencies updated
• CHANGELOG.md updated
• Documentation reviewed

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Metrics to Track

Metric	Current	9.3.0 Target
Test coverage (channelserver)	7.5%	40%+
Test coverage (overall)	21.4%	50%+
Panic/Fatal calls	61	<10 (critical paths only)
Ignored errors	~20	0
TODO/FIXME comments	18	<5
Outdated dependencies	4+	0
N+1 query patterns	4	0
Missing critical indexes	6	0
Unimplemented packets	393	380 (13 high-value done)

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Generated: 2026-02-01 Updated: 2026-02-01 - Added release milestones