IMPLEMENTATION_CHECKLIST.md

CODESYS REST API Implementation Checklist

Phase 1: Foundation Setup

Development Environment

• Create project structure following the design document
• Set up virtual environment with required Python packages
• Configure version control (git)
• Create configuration file structure for easy deployment

Core HTTP Server

• Implement BaseHTTPServer-based REST server
• Set up request routing mechanism
• Implement JSON request parsing and response formatting
• Create basic error handling system
• Set up logging framework
• Implement CORS support (if needed)

CODESYS Process Management

• Implement process launcher for CODESYS
• Create persistent session script mechanism
• Add health monitoring for CODESYS process
• Implement process recovery on crashes
• Set up inter-process communication mechanism
• Create cleanup routines for graceful shutdown

Script Generation Framework

• Create templating system for script generation
• Implement basic script execution engine
• Set up temporary file management for scripts
• Implement result capturing mechanism
• Create script cleanup routines

Phase 2: Core API Implementation

Session Management API

• Implement /session/start endpoint
• Implement /session/stop endpoint
• Implement /session/status endpoint
• Implement /session/restart endpoint
• Add comprehensive error handling for session operations
• Implement session timeout management

Project Operations API

• Implement /project/create endpoint
• Implement /project/open endpoint
• Implement /project/save endpoint
• Implement /project/close endpoint
• Implement /project/compile endpoint
• Add comprehensive error handling for project operations

POU Management API

• Implement /pou/create endpoint
• Implement /pou/code endpoint
• Implement /pou/list endpoint
• Implement /pou/{id} endpoint (implemented as part of /pou/list with params)
• Add support for different POU types (Program, Function, FunctionBlock)
• Implement error handling for POU operations

Script Execution API

• Implement /script/execute endpoint
• Create script validation mechanism
• Implement security checks for user scripts
• Add result formatting for script execution
• Implement error handling for script execution

Phase 3: Security & Monitoring

Authentication & Authorization

• Implement API key validation system
• Add request validation mechanisms
• Set up access control for different endpoints
• Implement rate limiting (if needed)
• Create secure storage for API keys
• Add HTTPS/TLS support

Logging & Monitoring

• Implement comprehensive logging system
• Add performance metrics collection
• Create monitoring dashboard endpoint(s)
• Implement log rotation
• Add alerting for critical errors
• Create system status endpoint

Error Handling Enhancements

• Refine error categorization system
• Implement detailed error messages
• Add retry mechanisms for transient errors
• Create specific error codes for API clients
• Implement global error handler

Performance Optimization

• Identify and fix performance bottlenecks
• Implement response caching where appropriate
• Optimize script execution
• Add connection pooling if needed
• Tune HTTP server settings for performance

Phase 4: Testing & Documentation

Comprehensive Testing

• Create unit tests for all components
• Implement integration tests for API endpoints
• Create load tests for performance evaluation
• Test edge cases and error conditions
• Implement automated test suite

Documentation

• Create API documentation (README.md contains API endpoints)
• Write user manual for API clients
• Create administrator guide for server setup
• Document developer onboarding process
• Add inline code documentation

Deployment Preparation

• Create installation script
• Prepare configuration templates
• Implement backup/restore procedures
• Create service definitions for auto-start
• Document deployment process

Final Review & Fixes

• Conduct code review of all components
• Address identified issues
• Perform final performance testing
• Review documentation for completeness
• Update based on review feedback

Additional Considerations

Windows Service Configuration

• Create Windows service wrapper
• Configure auto-restart on failure
• Set up proper logging for service
• Create service monitoring

Backup Strategy

• Implement configuration backup
• Create log archiving system
• Document recovery procedures
• Test restoration process

Security Hardening

• Conduct security review
• Implement input sanitation
• Add protection against common attacks
• Document security best practices