🔍 Code Extractor

Ensures a singleton AuditTrail node exists in a Neo4j database, creating it if absent, and returns its unique identifier.

Purpose

This function implements an idempotent operation to guarantee the existence of exactly one AuditTrail node in a Neo4j graph database. It first queries for an existing AuditTrail node and returns its UID if found. If no AuditTrail exists, it creates a new one with a generated UUID, creation timestamp, and default name. This is typically used during system initialization or before audit operations to ensure the audit infrastructure is in place. The function handles errors gracefully by logging exceptions and returning None on failure.

Source Code

def ensure_audit_trail_exists(driver: Driver) -> str:
    """
    Ensure that audit trail node exists in the database.
    
    Args:
        driver: Neo4j driver instance
        
    Returns:
        UID of the audit trail node
    """
    try:
        with driver.session() as session:
            # Check if audit trail exists
            result = session.run(
                """
                MATCH (t:AuditTrail)
                RETURN t.UID as uid
                LIMIT 1
                """
            )
            record = result.single()
            
            if record:
                return record["uid"]
            
            # Create audit trail
            audit_trail_uid = str(uuid.uuid4())
            
            session.run(
                """
                CREATE (t:AuditTrail {
                    UID: $uid,
                    createdDate: datetime(),
                    name: 'System Audit Trail'
                })
                """,
                {"uid": audit_trail_uid}
            )
            
            return audit_trail_uid
    except Exception as e:
        logger.error(f"Error ensuring audit trail exists: {e}")
        logger.error(traceback.format_exc())
        return None

Parameters

Parameter Details

driver: A Neo4j Driver instance that provides connection to the Neo4j database. This should be an active, authenticated driver object created using neo4j.GraphDatabase.driver(). The driver manages connection pooling and session creation for database operations.

Return Value

Type: str

Returns a string containing the UID (Unique Identifier) of the AuditTrail node as a UUID string format. If the AuditTrail already exists, returns its existing UID. If a new AuditTrail is created, returns the newly generated UUID. Returns None if an error occurs during database operations, which should be checked by the caller to handle failure cases.

Dependencies

• neo4j
• uuid
• logging
• traceback
• typing
• datetime
• CDocs

Required Imports

import logging
import uuid
import traceback
from typing import Dict, List, Any, Optional, Tuple
from neo4j import Driver, Session, Transaction
from datetime import datetime
from CDocs import guard_execution, db

Usage Example

from neo4j import GraphDatabase
import logging

# Setup logger
logger = logging.getLogger(__name__)
logger.setLevel(logging.INFO)

# Initialize Neo4j driver
driver = GraphDatabase.driver(
    'bolt://localhost:7687',
    auth=('neo4j', 'password')
)

try:
    # Ensure audit trail exists
    audit_uid = ensure_audit_trail_exists(driver)
    
    if audit_uid:
        print(f'Audit trail UID: {audit_uid}')
        # Use audit_uid for subsequent audit operations
    else:
        print('Failed to ensure audit trail exists')
        # Handle error case
finally:
    driver.close()

Best Practices

• Always check if the returned value is None before using it, as None indicates a failure in database operations
• Ensure the Neo4j driver is properly initialized and connected before calling this function
• This function should be called during application startup or before any audit operations
• The function is idempotent and safe to call multiple times - it will not create duplicate AuditTrail nodes
• Ensure proper logging configuration is in place to capture error messages from failed operations
• Close the Neo4j driver connection when done with all database operations to free resources
• Consider implementing retry logic at the caller level if database connectivity is unreliable
• The function uses a session context manager which automatically handles session cleanup
• Monitor logs for errors as the function logs detailed exception information including stack traces

Tags

Similar Components

AI-powered semantic similarity - components with related functionality:

• function ensure_audit_trail_exists_v1 98.4% similar

  Ensures a singleton AuditTrail node exists in a Neo4j database, creating it if necessary, and returns its unique identifier.

  From: /tf/active/vicechatdev/CDocs/db/schema_manager.py

• function get_or_create_audit_trail_uid 83.1% similar

  Retrieves the UID of an existing AuditTrail node from a Neo4j database, or creates a new AuditTrail node with a generated UID if one doesn't exist.

  From: /tf/active/vicechatdev/CDocs/utils/audit_trail.py

• function migrate_audit_events_v1 64.0% similar

  Migrates orphaned AuditEvent nodes from CDocs nodes to an AuditTrail node in a Neo4j graph database by deleting old relationships and creating new ones.

  From: /tf/active/vicechatdev/CDocs single class/db/schema_manager.py

• function migrate_audit_events 62.8% similar

  Migrates orphaned AuditEvent nodes from CDocs nodes to an AuditTrail node in a Neo4j graph database by deleting old relationships and creating new ones.

  From: /tf/active/vicechatdev/CDocs/db/schema_manager.py

• function node_exists 59.6% similar

  Checks if a node with a specific UID exists in a Neo4j graph database by querying for the node and returning a boolean result.

  From: /tf/active/vicechatdev/CDocs/db/db_operations.py