Variable value, loop iteration, function entry/exit, detailed diagnostics?
  → DEBUG

Successful operation, workflow step completed, state change confirmed?
  → INFO

Unexpected but handled: fallback used, retry attempt, deprecated call, approaching limit?
  → WARNING

Functionality failed: operation error, caught exception, feature broken?
  → ERROR (use logger.exception() in except blocks)

System-wide failure: cannot serve requests, out of resources, imminent crash?
  → CRITICAL

# ❌ WRONG: Exception logged as INFO
try:
    result = risky_operation()
except Exception as e:
    logger.info(f"Operation failed: {e}")  # Should be ERROR

# ✅ CORRECT: Use logger.exception() in except blocks
try:
    result = risky_operation()
except Exception as e:
    logger.exception("Operation failed")  # Automatically ERROR + stack trace

# ❌ WRONG: Normal operation logged as ERROR
user = get_user(user_id)
logger.error(f"Retrieved user {user_id}")  # Should be INFO or DEBUG

# ✅ CORRECT: Normal operations are INFO
user = get_user(user_id)
logger.info(f"Retrieved user {user_id}")

# ❌ WRONG: Fallback behavior logged as ERROR
cache_value = cache.get(key)
if cache_value is None:
    logger.error("Cache miss, using database")  # Should be WARNING or INFO
    value = db.query(key)

# ✅ CORRECT: Degraded mode is WARNING
cache_value = cache.get(key)
if cache_value is None:
    logger.warning("Cache miss, falling back to database")
    value = db.query(key)

# ❌ WRONG: Routine error logged as CRITICAL
if not user_id:
    logger.critical("Missing user_id parameter")  # Should be ERROR
    raise ValueError("user_id required")

# ✅ CORRECT: CRITICAL only for system-wide failures
if connection_pool_exhausted():
    logger.critical("Database connection pool exhausted, cannot serve requests")
    shutdown()

# ❌ WRONG: Missing stack trace
try:
    process_data()
except Exception as e:
    logger.error(f"Failed: {e}")  # No stack trace

# ✅ CORRECT: Use logger.exception() or exc_info=True
try:
    process_data()
except Exception as e:
    logger.exception("Data processing failed")  # Includes stack trace

# ✅ ALSO CORRECT: Explicit exc_info
try:
    process_data()
except Exception as e:
    logger.error("Data processing failed", exc_info=True)

# ❌ WRONG: Using root logger
logger = logging.getLogger()
logger.info("message")

# ✅ CORRECT: Named logger
logger = logging.getLogger(__name__)
logger.info("message")

# ❌ WRONG: Using print() for logging
print(f"Processing user {user_id}")

# ✅ CORRECT: Use logger
logger.info(f"Processing user {user_id}")

# ❌ WRONG: Logging sensitive data
logger.info(f"User authenticated: {username} / {password}")
logger.debug(f"API request: {api_key}")

# ✅ CORRECT: Redact sensitive information
logger.info(f"User authenticated: {username}")
logger.debug("API request authenticated")

FILE: path/to/file.py

LOGGING ISSUES:

Line 23: Severity too high
  Current: logger.error("Retrieved user data")
  Should be: logger.info("Retrieved user data")
  Reason: Normal successful operation should be INFO, not ERROR

Line 78: Missing exception context
  Current: logger.error(f"Failed: {e}")
  Should be: logger.exception("Operation failed")
  Reason: Use logger.exception() in except blocks for automatic stack trace

Line 134: Severity too low
  Current: logger.info("API call failed, retrying")
  Should be: logger.warning("API call failed, retrying")
  Reason: Retry indicates unexpected issue, should be WARNING

Line 201: Security violation
  Current: logger.debug(f"Authenticating with token: {api_token}")
  Should be: logger.debug("Authenticating with API")
  Reason: Never log credentials, tokens, or passwords

Line 234: Wrong logger pattern
  Current: logger = logging.getLogger()
  Should be: logger = logging.getLogger(__name__)
  Reason: Use named logger, not root logger

Line 289: Should use logger instead of print
  Current: print(f"Processing {count} items")
  Should be: logger.info(f"Processing {count} items")
  Reason: Use logging module for operational messages

SUMMARY: 6 logging issues found