calypso/docs/PHASE-D-PLAN.md

Phase D: Backend Hardening & Observability - Implementation Plan

🎯 Overview

Status: Ready to Start
Phase: D - Backend Hardening & Observability
Goal: Production-grade security, performance, and reliability

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✅ Already Completed (from Phase C)

• ✅ Enhanced monitoring (alerting engine, metrics, WebSocket)
• ✅ Alerting engine with rule-based monitoring
• ✅ Metrics collection for all components
• ✅ WebSocket event streaming

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📋 Phase D Tasks

1. Security Hardening 🔒

1.1 Password Hashing

• Current: Argon2id implementation is stubbed
• Task: Implement proper Argon2id password hashing
• Priority: High
• Files: backend/internal/auth/handler.go

1.2 Token Hashing

• Current: Session token hashing is simplified
• Task: Implement cryptographic hash for session tokens
• Priority: High
• Files: backend/internal/auth/handler.go

1.3 Rate Limiting

• Current: Not implemented
• Task: Add rate limiting middleware
• Priority: Medium
• Files: backend/internal/common/router/middleware.go

1.4 CORS Configuration

• Current: Allows all origins
• Task: Make CORS configurable via config file
• Priority: Medium
• Files: backend/internal/common/router/router.go, backend/internal/common/config/config.go

1.5 Input Validation

• Current: Basic validation
• Task: Enhanced input validation for all endpoints
• Priority: Medium
• Files: All handlers

1.6 Security Headers

• Current: Not implemented
• Task: Add security headers middleware (X-Frame-Options, X-Content-Type-Options, etc.)
• Priority: Medium
• Files: backend/internal/common/router/middleware.go

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2. Performance Optimization ⚡

2.1 Database Query Optimization

• Current: Basic queries
• Task: Optimize database queries (indexes, query plans)
• Priority: Medium
• Files: All service files

2.2 Connection Pooling

• Current: Basic connection pool
• Task: Optimize database connection pool settings
• Priority: Low
• Files: backend/internal/common/database/database.go

2.3 Response Caching

• Current: No caching
• Task: Add caching for read-heavy endpoints (health, metrics, etc.)
• Priority: Low
• Files: backend/internal/common/router/middleware.go

2.4 Request Timeout Configuration

• Current: Basic timeouts
• Task: Fine-tune request timeouts per endpoint type
• Priority: Low
• Files: backend/internal/common/router/router.go

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3. Comprehensive Testing 🧪

3.1 Unit Tests

• Current: No unit tests
• Task: Write unit tests for core services
• Priority: High
• Files: backend/internal/*/service_test.go

3.2 Integration Tests

• Current: Manual testing scripts
• Task: Automated integration tests
• Priority: Medium
• Files: backend/tests/integration/

3.3 Load Testing

• Current: Not tested
• Task: Load testing for API endpoints
• Priority: Low
• Files: scripts/load-test.sh

3.4 Security Testing

• Current: Not tested
• Task: Security vulnerability scanning
• Priority: Medium
• Files: Security test suite

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4. Error Handling Enhancement 🛡️

4.1 Error Messages

• Current: Some error messages could be more specific
• Task: Improve error messages with context
• Priority: Low
• Files: All handlers and services

4.2 Error Logging

• Current: Basic error logging
• Task: Enhanced error logging with stack traces
• Priority: Low
• Files: backend/internal/common/logger/logger.go

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🎯 Implementation Order

Priority 1: Security Hardening (Critical)

1. Password Hashing (Argon2id)
2. Token Hashing (Cryptographic)
3. Rate Limiting
4. CORS Configuration

Priority 2: Testing (Important)

1. Unit Tests for core services
2. Integration Tests for API endpoints
3. Security Testing

Priority 3: Performance (Nice to Have)

1. Database Query Optimization
2. Response Caching
3. Connection Pool Tuning

Priority 4: Polish (Enhancement)

1. Error Message Improvements
2. Security Headers
3. Input Validation Enhancements

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📊 Success Criteria

Security

• ✅ Argon2id password hashing implemented
• ✅ Cryptographic token hashing
• ✅ Rate limiting active
• ✅ CORS configurable
• ✅ Security headers present

Testing

• ✅ Unit test coverage >70%
• ✅ Integration tests for all endpoints
• ✅ Security tests passing

Performance

• ✅ Database queries optimized
• ✅ Response times <100ms for read operations
• ✅ Connection pool optimized

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🚀 Ready to Start

Next Task: Security Hardening - Password Hashing (Argon2id)

Would you like to start with:

1. Security Hardening (Password Hashing, Token Hashing, Rate Limiting)
2. Comprehensive Testing (Unit Tests, Integration Tests)
3. Performance Optimization (Database, Caching)

Which would you like to tackle first?