OOP Program Demonstration

DTCC CTM receives trade instructions for multiple asset classes. Implement an object-oriented validator that uses abstraction and polymorphism to apply the correct validation rules without placing all asset-specific logic in one conditional-heavy function.

Create an abstract TradeRule class with a validate(trade) method. Implement EquityRule, BondRule, and OptionRule subclasses. The validate_trades function must select the appropriate rule for each instruction and return validation results in the original order.

Formal Specification

Input trades is a list of dictionaries. Every dictionary contains id, asset_type, quantity, price, and settlement_days. Option trades also contain strike.

Return a list of dictionaries with id, valid, and errors. valid is true only when no rules are violated. Error messages must use the exact strings defined below.

• Equity: quantity must be positive, price must be positive, and settlement must be 1 or 2 days.
• Bond: quantity must be positive, price must be between 0 and 100 inclusive, and settlement must be between 1 and 3 days.
• Option: quantity must be positive, price must be nonnegative, strike must be positive, and settlement must be exactly 1 day.
• Unknown asset types produce one error: Unknown asset type.