graph_rag_server/examples/logging_example.py

"""
Example: Using the Logging System

This example demonstrates how to use the structured logging system
in the RAG System application.
"""

import sys
from pathlib import Path

# Add src to path for imports
sys.path.insert(0, str(Path(__file__).parent.parent / "src"))

from config import (
    configure_logging,
    configure_development_logging,
    configure_production_logging,
    get_logger,
    get_settings,
)


def example_basic_logging():
    """Example 1: Basic logging usage."""
    print("\n=== Example 1: Basic Logging ===\n")
    
    # Configure logging
    configure_logging(
        log_level="INFO",
        log_to_console=True,
        json_format=True,
    )
    
    # Get a logger
    logger = get_logger(__name__)
    
    # Log different types of messages
    logger.info("application_started", version="1.0.0", environment="development")
    logger.info("user_action", action="login", user_id="user_123")
    logger.warning("rate_limit_warning", user_id="user_123", requests=95, limit=100)
    logger.error("operation_failed", operation="save_document", error="Database timeout")


def example_context_binding():
    """Example 2: Context binding for request handling."""
    print("\n=== Example 2: Context Binding ===\n")
    
    configure_logging(log_level="INFO", log_to_console=True, json_format=True)
    logger = get_logger(__name__)
    
    # Simulate handling a request
    request_id = "req_12345"
    user_id = "user_789"
    
    # Bind context to logger
    request_logger = logger.bind(request_id=request_id, user_id=user_id)
    
    # All subsequent logs will include request_id and user_id
    request_logger.info("request_received", method="POST", path="/api/documents")
    request_logger.info("validating_input", fields=["content", "metadata"])
    request_logger.info("saving_document", document_id="doc_456")
    request_logger.info("request_completed", status_code=201, duration_ms=45)


def example_exception_logging():
    """Example 3: Logging exceptions with stack traces."""
    print("\n=== Example 3: Exception Logging ===\n")
    
    configure_logging(log_level="ERROR", log_to_console=True, json_format=True)
    logger = get_logger(__name__)
    
    try:
        # Simulate an error
        document_id = "doc_123"
        result = process_document(document_id)  # This will raise an error
    except Exception as e:
        logger.error(
            "document_processing_failed",
            document_id=document_id,
            error=str(e),
            error_type=type(e).__name__,
            exc_info=True,  # Include stack trace
        )


def process_document(document_id: str):
    """Simulate document processing that fails."""
    raise ValueError(f"Invalid document format for {document_id}")


def example_development_config():
    """Example 4: Development configuration."""
    print("\n=== Example 4: Development Configuration ===\n")
    
    # Use development configuration (human-readable format)
    configure_development_logging()
    logger = get_logger(__name__)
    
    logger.debug("debug_info", variable="value", state="initialized")
    logger.info("processing_started", task="data_import")
    logger.info("processing_completed", records_processed=1000)


def example_production_config():
    """Example 5: Production configuration."""
    print("\n=== Example 5: Production Configuration ===\n")
    
    # Use production configuration (file logging with JSON format)
    configure_production_logging(
        log_level="INFO",
        log_file="logs/example_app.log",
    )
    logger = get_logger(__name__)
    
    logger.info("application_started", version="1.0.0", environment="production")
    logger.info("database_connected", host="localhost", database="rag_system")
    logger.info("server_listening", host="0.0.0.0", port=8000)
    
    print("Logs written to: logs/example_app.log")


def example_with_settings():
    """Example 6: Using logging with application settings."""
    print("\n=== Example 6: Integration with Settings ===\n")
    
    # Get application settings
    settings = get_settings()
    
    # Configure logging based on environment
    if settings.environment == "production":
        configure_production_logging(
            log_level=settings.api.log_level,
            log_file="logs/app.log",
        )
    else:
        configure_development_logging(
            log_level=settings.api.log_level,
        )
    
    logger = get_logger(__name__)
    logger.info(
        "application_configured",
        environment=settings.environment,
        vector_db_type=settings.vector_db_type,
        log_level=settings.api.log_level,
    )


def example_structured_fields():
    """Example 7: Using structured fields effectively."""
    print("\n=== Example 7: Structured Fields ===\n")
    
    configure_logging(log_level="INFO", log_to_console=True, json_format=True)
    logger = get_logger(__name__)
    
    # Good: Use structured fields
    logger.info(
        "search_completed",
        query="machine learning",
        results_count=42,
        duration_ms=123,
        filters={"category": "AI", "year": 2024},
        top_score=0.95,
    )
    
    # Good: Log business events
    logger.info(
        "document_indexed",
        document_id="doc_789",
        title="Introduction to RAG",
        size_bytes=15360,
        chunks_count=12,
        embedding_model="text-embedding-3-small",
    )
    
    # Good: Log performance metrics
    logger.info(
        "batch_processing_completed",
        batch_id="batch_001",
        documents_processed=100,
        successful=98,
        failed=2,
        total_duration_ms=5432,
        avg_duration_ms=54.32,
    )


if __name__ == "__main__":
    print("=" * 70)
    print("Logging System Examples")
    print("=" * 70)
    
    try:
        example_basic_logging()
        example_context_binding()
        example_exception_logging()
        example_development_config()
        example_production_config()
        example_with_settings()
        example_structured_fields()
        
        print("\n" + "=" * 70)
        print("All examples completed successfully!")
        print("=" * 70)
    except Exception as e:
        print(f"\nExample failed with error: {e}")
        import traceback
        traceback.print_exc()
        sys.exit(1)