Enhanced OrderBook Implementation

[walterthesmart]

Overview

This PR significantly improves the orderbook smart contract, focusing on security, functionality, and user experience. The changes include comprehensive access controls, multi-token support, enhanced order management, and administrative features.

Changes

Security Enhancements

1. Access Control System

   • Added authorized-traders map to manage permitted traders
   • Implemented trader authorization checks via the is-authorized function
   • Added contract owner controls with contract-owner constant
   • Error constants for better error handling:

     (define-constant ERR-NOT-AUTHORIZED (err u401))
     (define-constant ERR-INVALID-PARAMS (err u400))

2. Emergency Controls

   • Added contract pause mechanism
   • Implemented toggle-pause function for emergency stops
   • Added pause checks in critical functions

   (define-data-var is-paused bool false)
   (define-public (toggle-pause)
     (begin
       (asserts! (is-eq tx-sender contract-owner) ERR-NOT-AUTHORIZED)
       (var-set is-paused (not (var-get is-paused)))
       (ok true)
     )
   )

Functional Improvements

1. Enhanced Order Structure

   • Added order status tracking
   • Implemented filled amount tracking
   • Added order expiry mechanism
   • New order fields:

   (define-map orders
     ((order-id uint))
     (
       (owner principal)
       (order-type (string-ascii 4))
       (amount uint)
       (filled-amount uint)
       (price uint)
       (timestamp uint)
       (expiry uint)
       (status (string-ascii 10))
       (token-contract principal)
     )
   )

2. Token Integration

   • Added SIP-010 trait support
   • Implemented token deposit/withdraw functionality
   • Added user balance tracking:

   (define-map user-balances
     ((user principal) (token-contract principal))
     ((balance uint))
   )

3. Fee System

   • Added protocol fee mechanism
   • Implemented configurable fee rate
   • Added fee calculation helper:

   (define-data-var protocol-fee-rate uint u25) ;; 0.25% fee rate
   (define-private (calculate-fee (amount uint))
     (/ (* amount (var-get protocol-fee-rate)) u10000)
   )

Administrative Features

1. Trader Management

   (define-public (authorize-trader (trader principal))
     (begin
       (asserts! (is-eq tx-sender contract-owner) ERR-NOT-AUTHORIZED)
       (map-set authorized-traders trader ((active true)))
       (ok true)
     )
   )
   
   (define-public (revoke-trader (trader principal))
     (begin
       (asserts! (is-eq tx-sender contract-owner) ERR-NOT-AUTHORIZED)
       (map-set authorized-traders trader ((active false)))
       (ok true)
     )
   )

2. Fee Management

   (define-public (set-protocol-fee (new-fee-rate uint))
     (begin
       (asserts! (is-eq tx-sender contract-owner) ERR-NOT-AUTHORIZED)
       (asserts! (<= new-fee-rate u1000) ERR-INVALID-PARAMS)
       (var-set protocol-fee-rate new-fee-rate)
       (ok true)
     )
   )

New Read-Only Functions

(define-read-only (get-order (order-id uint))
  (map-get? orders ((order-id order-id)))
)

(define-read-only (get-user-balance (user principal) (token-contract principal))
  (default-to u0 (get balance (map-get? user-balances ((user user) (token-contract token-contract)))))
)

(define-read-only (is-trader-authorized (trader principal))
  (is-authorized trader)
)

Testing Requirements

1. Authorization System

   • Test trader authorization/revocation
   • Verify unauthorized access is blocked
   • Test contract owner privileges

2. Order Management

   • Test order creation with various parameters
   • Verify order expiry mechanism
   • Test order cancellation
   • Verify minimum order size enforcement

3. Token Operations

   • Test token deposits
   • Test token withdrawals
   • Verify balance tracking accuracy

4. Administrative Functions

   • Test pause/unpause functionality
   • Test fee rate modifications
   • Verify trader management functions

Security Considerations

1. Access Control

   • Only authorized traders can place orders
   • Only contract owner can modify system parameters
   • Pause mechanism available for emergencies

2. Token Safety

   • Balance tracking prevents overdrafts
   • Secure token transfer implementation
   • Protected withdrawal mechanism

3. Order Protection

   • Order expiry prevents stale orders
   • Status tracking prevents invalid operations
   • Minimum order size prevents dust attacks

Migration Guide

1. Deploy new contract
2. Authorize initial set of traders
3. Set initial protocol fee rate
4. Configure minimum order size
5. Users must deposit tokens before trading

Documentation Updates

• Added contract comments and descriptions
• Updated function documentation
• Added error code documentation

Breaking Changes

1. Order structure modified
2. New authorization requirements
3. Token deposit requirement
4. Modified order placement parameters

Future Improvements

1. Consider implementing:
   • Market orders
   • Stop-loss orders
   • Order matching optimization
   • Enhanced fee distribution
   • Order book analytics

Reviewers

Please pay special attention to:

• Security controls implementation
• Token handling logic
• Fee calculation accuracy
• Authorization checks
• Error handling completeness

Testing Instructions

1. Run the provided test suite
2. Manual testing of critical paths
3. Verify error conditions
4. Test administrative functions
5. Validate token operations