baktainer/TODO.md

# Baktainer TODO List

This document tracks all identified issues, improvements, and future enhancements for the Baktainer project, organized by priority and category.

## 🎉 RECENT MAJOR ACCOMPLISHMENTS (January 2025)

### Dependency Injection & Testing Infrastructure Overhaul ✅ COMPLETED
- **Fixed Critical DI Bug**: Resolved singleton service instantiation that was returning factory Procs instead of actual service instances
- **Thread Pool Stability**: Replaced problematic Concurrent::FixedThreadPool with custom SimpleThreadPool implementation
- **100% Test Pass Rate**: Fixed all 30 failing tests, achieving complete test suite stability (100 examples, 0 failures)
- **Enhanced Architecture**: Completed comprehensive dependency injection system with proper service lifecycle management
- **Backup Features Complete**: Successfully implemented backup rotation, encryption, and monitoring with full test coverage

### Core Infrastructure Now Stable
All critical, high-priority, and operational improvement items have been completed. The application now has:
- Robust dependency injection with proper singleton management
- Comprehensive test coverage with reliable test infrastructure (121 examples, 0 failures)
- Complete backup workflow with rotation, encryption, and monitoring
- Production-ready error handling and security features
- **Full operational monitoring suite with health checks, status APIs, and dashboard**
- **Advanced label validation with schema-based error reporting**
- **Multi-channel notification system for backup events and system health**

## 🚨 CRITICAL (Security & Data Integrity)

### Security Vulnerabilities
- [x] **Add command injection protection** ✅ COMPLETED
  - ✅ Implemented proper shell argument parsing with whitelist validation
  - ✅ Added command sanitization and security checks
  - ✅ Added comprehensive security tests

- [x] **Improve SSL/TLS certificate handling** ✅ COMPLETED
  - ✅ Added certificate validation and error handling
  - ✅ Implemented support for both file and environment variable certificates
  - ✅ Added certificate expiration and key matching validation

- [x] **Review Docker socket security** ✅ COMPLETED
  - ✅ Documented security implications in SECURITY.md
  - ✅ Provided Docker socket proxy alternatives
  - ✅ Added security warnings in README.md

### Data Integrity
- [x] **Add backup verification** ✅ COMPLETED
  - ✅ Implemented backup file integrity verification with SHA256 checksums
  - ✅ Added database engine-specific content validation
  - ✅ Created backup metadata storage for tracking

- [x] **Implement atomic backup operations** ✅ COMPLETED
  - ✅ Write to temporary files first, then atomically rename
  - ✅ Implemented cleanup for failed backup attempts
  - ✅ Added comprehensive error handling and rollback

## 🔥 HIGH PRIORITY (Reliability & Correctness)

### Critical Bug Fixes
- [x] **Fix method name typos** ✅ COMPLETED
  - ✅ Fixed typos in previous implementation phases
  - ✅ Ensured consistent naming throughout codebase
  - ✅ All method names properly validated

- [x] **Fix SQLite API inconsistency** ✅ COMPLETED
  - ✅ SQLite class uses consistent instance method pattern
  - ✅ API consistency maintained across all database engines
  - ✅ All calling code updated accordingly

### Error Handling & Recovery
- [x] **Add comprehensive error handling for file operations** ✅ COMPLETED
  - ✅ Implemented comprehensive error handling for all file I/O operations
  - ✅ Added graceful handling of disk space, permissions, and I/O errors
  - ✅ Provided meaningful error messages for common failure scenarios
  - ✅ Created FileSystemOperations class for centralized file handling

- [x] **Implement proper resource cleanup** ✅ COMPLETED
  - ✅ All file operations use proper blocks or ensure cleanup
  - ✅ Added comprehensive cleanup for temporary files and directories
  - ✅ Implemented resource leak prevention in thread pool operations
  - ✅ Added atomic backup operations with rollback on failure

- [x] **Add retry mechanisms for transient failures** ✅ COMPLETED
  - ✅ Implemented exponential backoff for Docker API calls
  - ✅ Added retry logic for network-related backup failures
  - ✅ Configured maximum retry attempts and timeout values
  - ✅ Integrated retry mechanisms throughout backup workflow

- [x] **Improve thread pool error handling** ✅ COMPLETED
  - ✅ Implemented comprehensive backup attempt tracking
  - ✅ Added backup status reporting and monitoring system
  - ✅ Created dynamic thread pool with proper lifecycle management
  - ✅ Added backup monitoring with metrics collection and alerting

### Docker API Integration
- [x] **Add Docker API error handling** ✅ COMPLETED
  - ✅ Implemented comprehensive Docker daemon connection failure handling
  - ✅ Added retry logic for Docker API timeouts and transient failures
  - ✅ Provided clear error messages for Docker-related issues
  - ✅ Integrated Docker API error handling throughout application

- [x] **Implement Docker connection health checks** ✅ COMPLETED
  - ✅ Added Docker connectivity verification at startup
  - ✅ Implemented periodic health checks during operation
  - ✅ Added graceful degradation when Docker is unavailable
  - ✅ Created comprehensive Docker health monitoring system

## ⚠️ MEDIUM PRIORITY (Architecture & Maintainability)

### Code Architecture
- [x] **Refactor Container class responsibilities** ✅ COMPLETED
  - ✅ Extracted validation logic into ContainerValidator class
  - ✅ Separated backup orchestration into BackupOrchestrator class
  - ✅ Created dedicated FileSystemOperations class
  - ✅ Container class now focuses solely on container metadata

- [x] **Implement Strategy pattern for database engines** ✅ COMPLETED
  - ✅ Created common BackupStrategy interface for all database engines
  - ✅ Implemented consistent method signatures across all engines
  - ✅ Added BackupStrategyFactory for engine instantiation
  - ✅ Supports extensible engine registration

- [x] **Add proper dependency injection** ✅ COMPLETED
  - ✅ Created DependencyContainer for comprehensive service management
  - ✅ Removed global LOGGER constant dependency
  - ✅ Injected Docker client and all services properly
  - ✅ Made configuration injectable for better testing

- [x] **Create Configuration management class** ✅ COMPLETED
  - ✅ Centralized all environment variable access in Configuration class
  - ✅ Added comprehensive configuration validation at startup
  - ✅ Implemented default value management with type validation
  - ✅ Integrated configuration into dependency injection system

### Performance & Scalability
- [x] **Implement dynamic thread pool sizing** ✅ COMPLETED
  - ✅ Created DynamicThreadPool with runtime size adjustment
  - ✅ Added comprehensive monitoring for thread pool utilization
  - ✅ Implemented auto-scaling based on workload and queue pressure
  - ✅ Added thread pool statistics and resize event tracking

- [x] **Add backup operation monitoring** ✅ COMPLETED
  - ✅ Implemented BackupMonitor with comprehensive metrics tracking
  - ✅ Track backup duration, success rates, and file sizes
  - ✅ Added alerting system for backup failures and performance issues
  - ✅ Created metrics export functionality (JSON/CSV formats)

- [x] **Optimize memory usage for large backups** ✅ COMPLETED
  - ✅ Created StreamingBackupHandler for memory-efficient large backups
  - ✅ Implemented streaming backup data instead of loading into memory
  - ✅ Added backup compression options with container-level control
  - ✅ Implemented memory usage monitoring with configurable limits

## 📝 MEDIUM PRIORITY (Quality Assurance)

### Testing Infrastructure
- [x] **Set up testing framework** ✅ COMPLETED
  - ✅ Added RSpec testing framework to Gemfile
  - ✅ Configured test directory structure with unit and integration tests
  - ✅ Added test database containers for integration tests

- [x] **Write unit tests for core functionality** ✅ COMPLETED
  - ✅ Test all database backup command generation (including PostgreSQL aliases)
  - ✅ Test container discovery and validation logic
  - ✅ Test Runner class functionality and configuration

- [x] **Add integration tests** ✅ COMPLETED
  - ✅ Test full backup workflow with test containers
  - ✅ Test Docker API integration scenarios
  - ✅ Test error handling and recovery paths

- [x] **Implement test coverage reporting** ✅ COMPLETED
  - ✅ Added SimpleCov coverage tool
  - ✅ Achieved 94.94% line coverage (150/158 lines)
  - ✅ Added coverage reporting to test commands

- [x] **Fix dependency injection and test infrastructure** ✅ COMPLETED
  - ✅ Fixed critical DependencyContainer singleton bug that prevented proper service instantiation
  - ✅ Resolved ContainerValidator namespace issues throughout codebase
  - ✅ Implemented custom SimpleThreadPool to replace problematic Concurrent::FixedThreadPool
  - ✅ Fixed all test failures - achieved 100% test pass rate (100 examples, 0 failures)
  - ✅ Updated Container class API to support all_databases? method for proper backup orchestration
  - ✅ Enhanced BackupRotation tests to handle pre-existing test files correctly

### Documentation
- [x] **Add comprehensive API documentation** ✅ COMPLETED
  - ✅ Created comprehensive API_DOCUMENTATION.md with all public methods
  - ✅ Added detailed usage examples for each database engine
  - ✅ Documented all configuration options and environment variables
  - ✅ Included performance considerations and thread safety information

- [ ] **Create troubleshooting guide**
  - Document common error scenarios and solutions
  - Add debugging techniques and tools
  - Create FAQ for deployment issues

## 🔧 LOW PRIORITY (Enhancements)

### Feature Enhancements
- [x] **Implement backup rotation and cleanup** ✅ COMPLETED
  - ✅ Added configurable retention policies (by age, count, disk space)
  - ✅ Implemented automatic cleanup of old backups with comprehensive statistics
  - ✅ Added disk space monitoring and cleanup triggers with low-space detection

- [x] **Add backup encryption support** ✅ COMPLETED
  - ✅ Implemented backup file encryption at rest using OpenSSL
  - ✅ Added key management for encrypted backups with environment variable support
  - ✅ Support multiple encryption algorithms (AES-256-CBC, AES-256-GCM)

- [x] **Enhance logging and monitoring** ✅ COMPLETED
  - ✅ Implemented structured logging (JSON format) with custom formatter
  - ✅ Added comprehensive metrics collection and export via BackupMonitor
  - ✅ Created backup statistics tracking and reporting system

- [ ] **Add backup scheduling flexibility**
  - Support multiple backup schedules per container
  - Add one-time backup scheduling
  - Implement backup dependency management

### Operational Improvements
- [x] **Add health check endpoints** ✅ COMPLETED
  - ✅ Implemented comprehensive HTTP health check endpoint with multiple status checks
  - ✅ Added detailed backup status reporting API with metrics and history
  - ✅ Created responsive monitoring dashboard with real-time data and auto-refresh
  - ✅ Added Prometheus metrics endpoint for monitoring system integration

- [x] **Improve container label validation** ✅ COMPLETED
  - ✅ Implemented comprehensive schema validation for all backup labels
  - ✅ Added helpful error messages and warnings for invalid configurations
  - ✅ Created label help system with detailed documentation and examples
  - ✅ Enhanced ContainerValidator to use schema-based validation

- [x] **Add backup notification system** ✅ COMPLETED
  - ✅ Send notifications for backup completion, failure, warnings, and health issues
  - ✅ Support multiple notification channels: log, webhook, Slack, Discord, Teams
  - ✅ Added configurable notification thresholds and event-based filtering
  - ✅ Integrated notification system with backup monitor for automatic alerts

### Developer Experience
- [ ] **Add development environment setup**
  - Create docker-compose for development
  - Add sample database containers for testing
  - Document local development workflow

- [ ] **Implement backup dry-run mode**
  - Add flag to simulate backups without execution
  - Show what would be backed up and where
  - Validate configuration without performing operations

- [ ] **Add CLI improvements**
  - Add more command-line options for debugging
  - Implement verbose/quiet modes
  - Add configuration validation command

## 📊 FUTURE CONSIDERATIONS

### Advanced Features
- [ ] **Support for additional database engines**
  - Add Redis backup support
  - Implement MongoDB backup improvements
  - Add support for InfluxDB and time-series databases

- [ ] **Implement backup verification and restoration**
  - Add automatic backup validation
  - Create restoration workflow and tools
  - Implement backup integrity checking

- [ ] **Add cloud storage integration**
  - Support for S3, GCS, Azure Blob storage
  - Implement backup replication across regions
  - Add cloud-native backup encryption

- [ ] **Enhance container discovery**
  - Support for Kubernetes pod discovery
  - Add support for Docker Swarm services
  - Implement custom discovery plugins

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## Priority Legend
- 🚨 **CRITICAL**: Security vulnerabilities, data integrity issues
- 🔥 **HIGH**: Bugs, reliability issues, core functionality problems
- ⚠️ **MEDIUM**: Architecture improvements, maintainability
- 📝 **MEDIUM**: Quality assurance, testing, documentation
- 🔧 **LOW**: Feature enhancements, nice-to-have improvements
- 📊 **FUTURE**: Advanced features for consideration

## Getting Started
1. Begin with CRITICAL security issues
2. Fix HIGH priority bugs and reliability issues
3. Add testing infrastructure before making architectural changes
4. Implement MEDIUM priority improvements incrementally
5. Consider LOW priority enhancements based on user feedback

For each TODO item, create a separate branch, implement the fix, add tests, and ensure all existing functionality continues to work before merging.