Value Factories
Value Factories enable dynamic storage of on-chain snapshots within ComposableCoW’s “cabinet” system, allowing for storing on-chain values in the ComposableCoW cabinet at the time of order creation.
Key Technical Components
IValueFactory Interface
The simplest implementation requires a single getValue() function that reads on-chain state and returns a bytes32 value that gets stored in the cabinet.
Cabinet Storage Structure
ComposableCoW maintains a nested mapping using:
- First key: Owner address
- Second key: Context identifier
- Value: Corresponding
bytes32 value
Primary Use Cases
1. Time-based Orders
The CurrentBlockTimestampFactory captures block timestamps, enabling time-locked trading strategies and expiration mechanisms.
2. Price Snapshots
The ChainlinkPriceFactory example demonstrates capturing token prices via oracle data at creation time.
3. Balance Snapshots
The TokenBalanceFactory stores account balances as contextual references.
4. Composite Storage
Multiple values can be packed into single bytes32 entries for efficiency.
Implementation Pattern
Orders access cabinet values through:
ComposableCoW(msg.sender).cabinet(owner, ctx)
Value factory calls happen during transaction execution (not view calls), necessitating lightweight computational design to manage gas costs effectively.
