# Production Changes Unit Tests

## Overview
This document describes the unit tests created for the production changes in the top 2 commits. The tests ensure that the enhanced error handling, logging, and DirectFileHandler improvements work correctly in production environments.

## Test Files Created

### 1. `test_production_changes.py`
Comprehensive tests for all production improvements:

#### TestEnhancedErrorHandling
- **test_load_extension_with_structured_logging**: Verifies structured logging with proper ERROR/DEBUG levels
- **test_graceful_degradation_on_error**: Ensures extension failures don't crash JupyterLab
- **test_stack_trace_logged_at_debug_level**: Confirms stack traces use DEBUG level, not ERROR

#### TestDirectFileHandler
- **test_inherits_from_static_file_handler**: Verifies proper inheritance
- **test_javascript_mime_type_override**: Tests MIME type override for JS files
- **test_non_javascript_mime_type_fallback**: Tests fallback for non-JS files
- **test_cors_headers_set**: Verifies CORS headers for cross-origin requests
- **test_cache_control_headers**: Tests cache control for fresh content

#### TestArtifactValidation
- **test_artifact_validation_success**: Tests successful artifact validation logging
- **test_artifact_validation_missing_file**: Tests warning when specific files are missing
- **test_artifact_validation_missing_directory**: Tests error when entire directory is missing

#### TestProductionLogging
- **test_handler_setup_logging**: Verifies proper handler setup logging
- **test_handler_setup_error_logging**: Tests error logging with stack traces at DEBUG level
- **test_logging_configuration_format**: Tests structured logging format
- **test_debug_logging_environment**: Tests debug mode via environment variable

#### TestLSPInitializationLogging
- **test_lsp_initialization_success_logging**: Tests successful LSP initialization logging
- **test_lsp_initialization_missing_artifacts_logging**: Tests enhanced error messages for missing artifacts

#### TestOfflineFirstDesign
- **test_no_external_dependencies**: Verifies no external URL dependencies
- **test_offline_operation_messaging**: Tests offline operation messaging in logs

### 2. `test_client_html.py`
Tests for client.html production improvements:

#### TestClientHtmlChanges
- **test_client_html_exists**: Verifies client.html file exists
- **test_client_html_content_structure**: Tests expected production elements
- **test_csp_headers_allow_websockets**: Verifies WebSocket connections in CSP
- **test_offline_first_design_comments**: Tests production comments are present
- **test_dynamic_url_resolution_logic**: Tests dynamic URL construction
- **test_error_handling_enhancements**: Tests enhanced error messages
- **test_no_external_dependencies**: Verifies offline-first design
- **test_amazon_q_chat_initialization**: Tests proper chat initialization
- **test_quick_action_commands**: Tests quick action commands
- **test_local_storage_usage**: Tests local storage for user preferences

#### TestClientHtmlSecurity
- **test_content_security_policy**: Tests restrictive but functional CSP
- **test_no_inline_scripts_without_nonce**: Tests proper nonce usage
- **test_no_eval_or_unsafe_inline_js**: Tests no unsafe JavaScript practices

#### TestClientHtmlPerformance
- **test_minimal_external_resources**: Tests minimal external resource loading
- **test_css_inlined_for_performance**: Tests inlined CSS for performance
- **test_script_loading_optimization**: Tests optimized script loading

### 3. Enhanced Existing Tests

#### Updated `test_init.py`
- **test_load_jupyter_server_extension_with_enhanced_error_handling**: Tests structured logging improvements
- **test_load_jupyter_server_extension_graceful_degradation**: Tests graceful failure handling
- **test_initialize_lsp_server_missing_artifacts_enhanced_logging**: Tests enhanced error messages
- **test_initialize_lsp_server_with_enhanced_logging**: Tests production logging improvements

#### Updated `test_handlers.py`
- **TestDirectFileHandler**: New test class for DirectFileHandler improvements
- **test_setup_handlers_success_with_artifact_validation**: Tests artifact validation during setup
- **test_setup_handlers_exception_with_enhanced_logging**: Tests enhanced error logging
- **test_artifact_validation_logging**: Tests artifact validation logging

## Key Testing Areas

### 1. Error Handling
- **Structured Logging**: ERROR level for main messages, DEBUG for stack traces
- **Graceful Degradation**: Extension failures don't crash JupyterLab
- **Clear Error Messages**: Meaningful messages for troubleshooting

### 2. Logging Improvements
- **Production Format**: Structured logging with timestamps and levels
- **Appropriate Levels**: INFO for operations, DEBUG for troubleshooting
- **Environment Awareness**: Debug mode via JUPYTER_LOG_LEVEL

### 3. DirectFileHandler
- **MIME Type Override**: Correct content type for JavaScript files
- **CORS Headers**: Enable cross-origin requests
- **Cache Control**: Prevent stale content during development
- **StaticFileHandler Inheritance**: Proper inheritance for performance

### 4. Artifact Validation
- **Early Detection**: Missing dependencies detected during startup
- **Clear Messages**: Helpful error messages for missing artifacts
- **Offline Operation**: Proper messaging about SageMaker Distribution requirements

### 5. Client-Side Improvements
- **Dynamic URL Resolution**: Works in various deployment contexts
- **Security**: Restrictive CSP with functional WebSocket support
- **Performance**: Inlined CSS, optimized script loading
- **Error Handling**: Graceful degradation for missing artifacts

## Running the Tests

### Individual Test Files
```bash
# Run all production tests
python -m pytest sagemaker_gen_ai_jupyterlab_extension/tests/test_production_changes.py -v

# Run client HTML tests
python -m pytest sagemaker_gen_ai_jupyterlab_extension/tests/test_client_html.py -v

# Run specific test classes
python -m pytest sagemaker_gen_ai_jupyterlab_extension/tests/test_production_changes.py::TestEnhancedErrorHandling -v
```

### Using the Test Runner
```bash
# Run all production-related tests
python run_production_tests.py
```

### Test Coverage Areas
The tests cover the following production improvements:

1. **Enhanced Error Handling** (Commit 6e78ddd)
   - Structured logging with proper levels
   - Stack traces at DEBUG level
   - Graceful degradation

2. **DirectFileHandler Improvements** (Commit 6e78ddd)
   - MIME type override for JavaScript
   - CORS and cache headers
   - StaticFileHandler inheritance

3. **Artifact Validation** (Commit 6e78ddd)
   - SageMaker Distribution artifact checking
   - Clear error messages for missing components
   - Offline operation messaging

4. **Client-Side Enhancements** (Commit 6e78ddd)
   - Dynamic base URL resolution
   - Enhanced error handling
   - Production logging

5. **Offline-First Architecture** (Commit c14b0c8)
   - No external dependencies
   - Local artifact serving
   - SageMaker Distribution integration

## Benefits of These Tests

### 1. Production Readiness
- Ensures proper error handling in production environments
- Validates logging configuration for monitoring systems
- Tests graceful degradation scenarios

### 2. Offline-First Validation
- Confirms no external dependencies
- Tests local artifact serving
- Validates SageMaker Distribution integration

### 3. Security and Performance
- Tests Content Security Policy configuration
- Validates CORS header setup
- Ensures optimized resource loading

### 4. Maintainability
- Comprehensive test coverage for production changes
- Clear test documentation and structure
- Easy to run and validate changes

## Test Execution Results
The tests validate that all production improvements work correctly:
- ✅ Enhanced error handling with structured logging
- ✅ DirectFileHandler improvements for offline operation
- ✅ Artifact validation with clear error messages
- ✅ Client-side dynamic URL resolution
- ✅ Security policy configuration
- ✅ Performance optimizations