YNAB MCP Server

"""Input validation utilities for YNAB MCP.""" from __future__ import annotations from datetime import datetime from .exceptions import YNABValidationError def validate_date(date_str: str, param_name: str = "date") -> str: """Validate and normalize date string in YYYY-MM-DD format. Args: date_str: Date string to validate param_name: Name of the parameter for error messages Returns: Validated date string Raises: YNABValidationError: If date format is invalid """ if not date_str: raise YNABValidationError(f"{param_name} cannot be empty") if not isinstance(date_str, str): raise YNABValidationError(f"{param_name} must be a string") try: datetime.strptime(date_str, "%Y-%m-%d") return date_str except ValueError as e: raise YNABValidationError( f"Invalid {param_name} format. Expected YYYY-MM-DD, got '{date_str}'" ) from e def validate_budget_id(budget_id: str) -> str: """Validate budget ID. Args: budget_id: Budget ID to validate Returns: Validated and stripped budget ID Raises: YNABValidationError: If budget_id is invalid """ if not budget_id or not isinstance(budget_id, str): raise YNABValidationError("budget_id must be a non-empty string") budget_id = budget_id.strip() if not budget_id: raise YNABValidationError("budget_id cannot be empty or whitespace") return budget_id def validate_amount(amount: float, param_name: str = "amount") -> float: """Validate amount parameter. Args: amount: Amount to validate param_name: Name of the parameter for error messages Returns: Validated amount Raises: YNABValidationError: If amount is invalid """ if not isinstance(amount, (int, float)): raise YNABValidationError(f"{param_name} must be a number") return float(amount) def validate_pagination( limit: int | None = None, page: int | None = None, max_limit: int = 500, default_limit: int = 100, ) -> tuple[int, int]: """Validate and normalize pagination parameters. Args: limit: Number of items per page page: Page number (1-indexed) max_limit: Maximum allowed limit default_limit: Default limit if not specified Returns: Tuple of (validated_limit, validated_page) Raises: YNABValidationError: If pagination parameters are invalid """ # Validate and normalize limit if limit is None: validated_limit = default_limit else: if not isinstance(limit, int) or limit <= 0: raise YNABValidationError("limit must be a positive integer") validated_limit = min(limit, max_limit) # Validate and normalize page if page is None: validated_page = 1 else: if not isinstance(page, int) or page < 1: raise YNABValidationError("page must be a positive integer (1-indexed)") validated_page = page return validated_limit, validated_page def validate_frequency(frequency: str) -> str: """Validate scheduled transaction frequency. Args: frequency: Frequency string to validate Returns: Validated frequency string Raises: YNABValidationError: If frequency is invalid """ valid_frequencies = { "never", "daily", "weekly", "everyOtherWeek", "twiceAMonth", "every4Weeks", "monthly", "everyOtherMonth", "every3Months", "every4Months", "twiceAYear", "yearly", "everyOtherYear", } if not frequency or not isinstance(frequency, str): raise YNABValidationError("frequency must be a non-empty string") if frequency not in valid_frequencies: raise YNABValidationError( f"Invalid frequency '{frequency}'. Must be one of: {', '.join(sorted(valid_frequencies))}" ) return frequency def validate_cleared_status(cleared: str) -> str: """Validate transaction cleared status. Args: cleared: Cleared status to validate Returns: Validated cleared status Raises: YNABValidationError: If cleared status is invalid """ valid_statuses = {"cleared", "uncleared", "reconciled"} if not cleared or not isinstance(cleared, str): raise YNABValidationError("cleared status must be a non-empty string") if cleared not in valid_statuses: raise YNABValidationError( f"Invalid cleared status '{cleared}'. Must be one of: {', '.join(sorted(valid_statuses))}" ) return cleared