Files
unraid-mcp/unraid_mcp/core/exceptions.py
Jacob Magar f76e676fd4 test: close critical coverage gaps and harden PR review fixes
Critical bug fixes from PR review agents:
- client.py: eager asyncio.Lock init, Final[frozenset] for _SENSITIVE_KEYS,
  explicit 429 ToolError after retries exhausted, removed lazy _get_client_lock()
  and _RateLimiter._get_lock() patterns
- exceptions.py: use builtin TimeoutError (UP041), explicit handler before broad
  except so asyncio timeouts get descriptive messages
- docker.py: add update_all to DESTRUCTIVE_ACTIONS (was missing), remove dead
  _MUTATION_ACTIONS constant
- manager.py: _cap_log_content returns new dict (immutable), lock write to
  resource_data, clean dead task from active_subscriptions after loop exits
- diagnostics.py: fix inaccurate comment about semicolon injection guard
- health.py: narrow except ValueError in _safe_display_url, fix TODO comment

New test coverage (98 tests added, 529 → 598 passing):
- test_subscription_validation.py: 27 tests for _validate_subscription_query
  (security-critical allow-list, forbidden keyword guards, word-boundary test)
- test_subscription_manager.py: 12 tests for _cap_log_content
  (immutability, truncation, nesting, passthrough)
- test_client.py: +57 tests — _RateLimiter (token math, refill, sleep-on-empty),
  _QueryCache (TTL, invalidation, is_cacheable), 429 retry loop (1/2/3 failures)
- test_health.py: +10 tests for _safe_display_url (credential strip, port,
  path/query removal, malformed IPv6 → <unparseable>)
- test_notifications.py: +7 importance enum and field length validation tests
- test_rclone.py: +7 _validate_config_data security guard tests
- test_storage.py: +15 (tail_lines bounds, format_kb, safe_get)
- test_docker.py: update_all now requires confirm=True + new guard test
- test_destructive_guards.py: update audit to include update_all

Co-authored-by: Claude <noreply@anthropic.com>
2026-02-18 01:28:40 -05:00

58 lines
1.8 KiB
Python

"""Custom exceptions for Unraid MCP Server.
This module defines custom exception classes for consistent error handling
throughout the application, with proper integration to FastMCP's error system.
"""
import contextlib
import logging
from collections.abc import Iterator
from fastmcp.exceptions import ToolError as FastMCPToolError
class ToolError(FastMCPToolError):
"""User-facing error that MCP clients can handle.
This is the main exception type used throughout the application for
errors that should be presented to the user/LLM in a friendly way.
Inherits from FastMCP's ToolError to ensure proper MCP protocol handling.
"""
pass
@contextlib.contextmanager
def tool_error_handler(
tool_name: str,
action: str,
logger: logging.Logger,
) -> Iterator[None]:
"""Context manager that standardizes tool error handling.
Re-raises ToolError as-is. Gives TimeoutError a descriptive message.
Catches all other exceptions, logs them with full traceback, and wraps them
in ToolError with a descriptive message.
Args:
tool_name: The tool name for error messages (e.g., "docker", "vm").
action: The current action being executed.
logger: The logger instance to use for error logging.
"""
try:
yield
except ToolError:
raise
except TimeoutError as e:
logger.error(
f"Timeout in unraid_{tool_name} action={action}: request exceeded time limit",
exc_info=True,
)
raise ToolError(
f"Request timed out executing {tool_name}/{action}. The Unraid API did not respond in time."
) from e
except Exception as e:
logger.error(f"Error in unraid_{tool_name} action={action}: {e}", exc_info=True)
raise ToolError(f"Failed to execute {tool_name}/{action}: {e!s}") from e