# Implementation Plan: Operational Resilience and Error Handling

- [x] 1. Set up operational infrastructure and core error handling
  - Create operational package structure with proper __init__.py files
  - Implement ErrorHandler class with error classification and context capture
  - Implement StructuredLogger class with JSON formatting and multiple output targets
  - Create OperationalError exception class and ErrorContext dataclass
  - _Requirements: 1.1, 1.2, 1.3, 1.4, 1.5_

- [x] 1.1 Write unit tests for error handling components
  - Create test cases for ErrorHandler error classification and context capture
  - Write tests for StructuredLogger output formatting and multiple targets
  - Test OperationalError exception handling and context preservation
  - _Requirements: 1.1, 1.2, 1.3_

- [x] 2. Implement retry management and resilience patterns
  - Create RetryManager class with exponential backoff and jitter
  - Implement CircuitBreaker class with state management and recovery logic
  - Add rate limit detection and handling for ServiceNow API responses
  - Integrate retry and circuit breaker patterns with configurable policies
  - _Requirements: 2.1, 2.2, 2.3, 2.4, 2.5_

- [x] 2.1 Write unit tests for resilience components
  - Test RetryManager exponential backoff calculations and jitter application
  - Write CircuitBreaker state transition tests and recovery timeout logic
  - Test rate limit detection and appropriate delay calculations
  - _Requirements: 2.1, 2.2, 2.3, 2.4, 2.5_

- [ ] 3. Enhance ServiceNow API client with operational capabilities
  - Modify ServiceNowAPIClient to integrate ErrorHandler and StructuredLogger
  - Add RetryManager and CircuitBreaker to API request execution
  - Implement enhanced error parsing for ServiceNow-specific error responses
  - Add operation timing and success/failure tracking to all API methods
  - _Requirements: 1.1, 1.2, 1.3, 2.1, 2.2, 2.3_

- [ ] 3.1 Write integration tests for enhanced API client
  - Test error handling integration with actual ServiceNow error responses
  - Write tests for retry behavior with simulated network failures
  - Test circuit breaker integration with consecutive API failures
  - _Requirements: 1.1, 1.2, 2.1, 2.2, 2.3_

- [ ] 4. Implement data validation and integrity checks
  - Add comprehensive validation to UniFi data transformation functions
  - Implement pre-load and post-load data integrity verification
  - Create detailed field-level validation error reporting
  - Add relationship validation before creating ServiceNow record links
  - Implement rollback capabilities for failed batch operations
  - _Requirements: 3.1, 3.2, 3.3, 3.4, 3.5_

- [ ] 4.1 Write unit tests for data validation
  - Test field-level validation with various invalid data scenarios
  - Write tests for relationship validation and orphaned record detection
  - Test rollback functionality with partial batch failures
  - _Requirements: 3.1, 3.2, 3.3, 3.4, 3.5_

- [x] 5. Create health monitoring and metrics collection
  - Implement HealthMonitor class with ServiceNow connectivity checks
  - Add credential availability and system resource monitoring
  - Create MetricsCollector class for operation performance tracking
  - Implement health check endpoints and overall status calculation
  - Add performance metrics collection with P95 response times and error rates
  - _Requirements: 4.1, 4.2, 4.3, 4.4, 4.5_

- [x] 5.1 Write unit tests for monitoring components
  - Test HealthMonitor check execution and status aggregation
  - Write tests for MetricsCollector performance tracking and calculations
  - Test health check endpoint responses and status determination
  - _Requirements: 4.1, 4.2, 4.3, 4.4, 4.5_

- [ ] 6. Implement secure credential management following beast principles
  - Enhance credential loading to follow 1Password canonical source principle
  - Add secure credential access logging without exposing sensitive values
  - Implement credential validation with secure error messaging
  - Add support for multiple authentication method fallbacks with security prioritization
  - Create comprehensive audit trail for all data modification operations
  - _Requirements: 5.1, 5.2, 5.3, 5.4, 5.5_

- [ ] 6.1 Write security tests for credential management
  - Test 1Password CLI integration and fallback behavior
  - Write tests for secure error messaging without credential exposure
  - Test audit trail generation and tamper-evidence
  - _Requirements: 5.1, 5.2, 5.3, 5.4, 5.5_

- [ ] 7. Implement graceful degradation and partial failure handling
  - Add fallback to base cmdb_ci table when specific ServiceNow tables unavailable
  - Implement partial batch operation success handling with detailed reporting
  - Create stale data caching when UniFi API temporarily unavailable
  - Add graceful degradation for missing ServiceNow plugin dependencies
  - Implement read-only mode with write operation queuing during service outages
  - _Requirements: 6.1, 6.2, 6.3, 6.4, 6.5_

- [ ] 7.1 Write integration tests for graceful degradation
  - Test table fallback behavior with unavailable ServiceNow tables
  - Write tests for partial batch failure handling and reporting
  - Test read-only mode activation and write operation queuing
  - _Requirements: 6.1, 6.2, 6.3, 6.4, 6.5_

- [x] 8. Create configuration management and environment detection
  - Implement OperationalConfig class with Pydantic validation
  - Add environment detection and adaptive behavior configuration
  - Create configuration validation with clear error messaging for invalid settings
  - Implement environment-specific logging levels and output format configuration
  - Add startup configuration validation with fail-fast error reporting
  - _Requirements: 7.1, 7.2, 7.3, 7.4, 7.5_

- [x] 8.1 Write configuration tests
  - Test configuration validation with various invalid setting scenarios
  - Write tests for environment detection and adaptive behavior
  - Test startup validation and fail-fast error reporting
  - _Requirements: 7.1, 7.2, 7.3, 7.4, 7.5_

- [x] 9. Implement comprehensive operation reporting and statistics
  - Create detailed operation reports with record counts, success rates, and timing
  - Add data quality issue reporting with specific problem identification
  - Implement relationship processing reports with linking success rates
  - Add performance bottleneck identification and optimization suggestions
  - Create postmortem-ready logging with key events for LLM analysis
  - Implement historical statistics collection for trend analysis
  - _Requirements: 8.1, 8.2, 8.3, 8.4, 8.5_

- [x] 9.1 Write reporting tests
  - Test operation report generation with various success/failure scenarios
  - Write tests for data quality issue detection and reporting
  - Test historical statistics collection and trend analysis
  - _Requirements: 8.1, 8.2, 8.3, 8.4, 8.5_

- [x] 10. Ensure beast project compliance and quality standards
  - Update project structure to follow beast naming conventions and patterns
  - Integrate with existing PyPI publishing and SonarCloud quality gates
  - Implement structured logging appropriate for Python beast projects
  - Add quality gate enforcement preventing bypass of quality checks
  - Update agent guidance documentation with operational resilience patterns
  - _Requirements: 9.1, 9.2, 9.3, 9.4, 9.5_

- [x] 10.1 Write compliance tests
  - Test integration with existing quality gates and CI/CD pipeline
  - Write tests for beast naming convention compliance
  - Test structured logging format compatibility with beast standards
  - _Requirements: 9.1, 9.2, 9.3, 9.4, 9.5_

- [ ] 11. Create comprehensive examples and update documentation
  - Update complete_workflow.py example to demonstrate operational features
  - Create operational_resilience_demo.py showing error handling and recovery
  - Add health_check_example.py demonstrating monitoring capabilities
  - Update README.md with operational resilience feature documentation
  - Create operational troubleshooting guide for common issues
  - _Requirements: All requirements - demonstration and documentation_

- [ ] 11.1 Write documentation tests
  - Test example scripts for correctness and completeness
  - Write tests to validate documentation code snippets
  - Test troubleshooting guide scenarios
  - _Requirements: All requirements - validation of examples and documentation_