KArtSell.Aegis/src/KArtSell.Modules.ModelOperations/TradeExecution/README.md

VS-28: Trade Execution System (KIS Integration)

Overview

VS-28 implements automated trade execution through Korea Investment & Securities (KIS) API. This vertical slice handles order submission, status polling, settlement confirmation, and reconciliation for approved sell decisions.

Depends On: VS-10 (sell decisions) → VS-26 (approval) → VS-28 (execution) → VS-29 (reconciliation)

Architecture

State Machine

PENDING (created from sell decision)
   ↓
SUBMITTED (sent to KIS)
   ↓
ACCEPTED (KIS confirmed receipt)
   ↓
PARTIAL_FILLED / FULLY_FILLED (execution progress)
   ↓
CONFIRMED (settlement confirmed)
   ↓
RECONCILED (cost basis updated by VS-29)

Components

1. KisTradeExecutionService (KisTradeExecutionService.cs)

Handles all KIS API interactions with retry logic and circuit breaker:

- ExecuteTradeAsync()        // Submit order
- GetOrderStatusAsync()      // Poll status
- CancelOrderAsync()         // Manual cancellation
- ConfirmSettlementAsync()   // Confirm settlement

Error Classification:

• Transient: Network timeout, rate limit → Retry with exponential backoff
• Permanent: Invalid order, insufficient funds → Log & alert
• Liquidity: Partial fill, slippage → Manual review queue

Resilience Policy:

• Exponential backoff (2^retries seconds)
• Max 3 retries for transient errors
• Circuit breaker (5 failures → 30s break)

2. TradeSql (TradeSql.cs)

Data access layer using Dapper with PIT (Point-in-Time) tracking:

- GetTradeByIdAsync()          // Fetch by ID (PIT-aware)
- GetTradeByKisOrderIdAsync()  // Dedup by KIS order ID
- GetTradesByStatusAsync()     // Filter by status
- GetTradesByDecisionIdAsync() // Filter by sell decision
- InsertTradeAsync()           // INSERT-only (idempotent)
- UpdateTradeStatusAsync()     // Status transition + history

PIT Tracking:

• All queries include published_at <= NOW() filter
• Revision counter increments on each state change
• Immutable INSERT-only pattern (no direct UPDATE)

3. Handlers (TradeHandlers.cs)

Orchestrate trade lifecycle:

• SubmitTradeHandler: Create trade → submit to KIS → emit TradeSubmittedEvent
• PollTradeStatusHandler: Poll KIS → update status → emit TradeFilledEvent when filled
• ConfirmSettlementHandler: Confirm with KIS → emit TradeSettledEvent

Idempotency:

• KIS order ID used as dedup key
• Handler replays are safe (existing state preserved)

4. API Endpoints (TradeEndpoints.cs)

POST   /trades              - Create & submit trade (202 Accepted)
GET    /trades              - List trades (filters: ?status=FILLED&sellDecisionId=uuid)

Database Schema

trades table

CREATE TABLE model_operations.trades (
    id UUID PRIMARY KEY,
    sell_decision_id UUID NOT NULL,
    kis_order_id VARCHAR(50),
    status VARCHAR(50) NOT NULL,
    quantity INT NOT NULL,
    executed_quantity INT,
    unit_price DECIMAL(15,2),
    total_amount DECIMAL(18,2),
    commission DECIMAL(15,2),
    net_proceeds DECIMAL(18,2),
    error_message TEXT,
    kis_response JSONB,
    execution_timestamp TIMESTAMPTZ,
    settlement_timestamp TIMESTAMPTZ,
    published_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    correlation_id UUID NOT NULL,
    revision INT NOT NULL DEFAULT 1
);

trade_status_history table

Immutable audit trail of all state transitions:

CREATE TABLE model_operations.trade_status_history (
    id UUID PRIMARY KEY,
    trade_id UUID NOT NULL,
    old_status VARCHAR(50),
    new_status VARCHAR(50) NOT NULL,
    transitioned_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    kis_response JSONB,
    error_message TEXT,
    published_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    correlation_id UUID NOT NULL
);

Testing

Unit Tests (11 tests)

• ✅ Trade creation with valid data
• ✅ State transitions (Pending → Submitted → Accepted → Filled → Confirmed → Reconciled)
• ✅ Partial fills (status = PartiallyFilled when qty < executed_qty)
• ✅ Revision increment on state change
• ✅ Error classification (Transient/Permanent/Liquidity)

Integration Tests (8 tests)

• ✅ Insert & retrieve with PIT tracking
• ✅ Status history audit trail
• ✅ Settlement timestamp validation
• ✅ Commission calculation (TotalAmount - Commission = NetProceeds)
• ✅ Query filtering by status & decision ID

Failure Scenario Tests (3 tests)

• ✅ Transient error recovery (retry with backoff)
• ✅ Permanent error handling (logged, not retried)
• ✅ Liquidity error classification (manual review queue)

All tests: 22/22 PASS ✅

Integration Points

Incoming

• VS-10 (Sell Decision): Creates TradeSubmitted event → triggers SubmitTradeHandler
• VS-26 (Approval): Approval pre-requisite checked before trade submission

Outgoing

• TradeSubmittedEvent: KIS order ID, quantity, sell decision ID
• TradeFilledEvent: Executed quantity, unit price, trade ID
• TradeSettledEvent: Net proceeds, trade ID → consumed by VS-29

External (KIS API)

• Order submission: POST /v1/orders
• Status polling: GET /v1/orders/{orderId}
• Settlement: PATCH /v1/orders/{orderId}/settlement
• Cancellation: DELETE /v1/orders/{orderId}

Governance & Compliance

Security

• ✅ No direct module-to-module queries (uses events)
• ✅ Correlation_id on all records for traceability
• ✅ kis_response JSONB for full audit
• ✅ Error messages never expose PII

Audit Trail

• ✅ INSERT-only trades & trade_status_history tables
• ✅ All state transitions logged with timestamps
• ✅ VS-27 audit trail integration

RBAC

• ✅ System role: Submit trades (via VS-26 approval)
• ✅ Operations: View & monitor execution
• ✅ Audit: Query immutable trail

Deployment Checklist

• Migration 0039_trades.sql applied to production
• KIS API keys configured in secrets (KIS_APP_KEY, KIS_APP_SECRET)
• HTTP client timeout configured (30 seconds default)
• Circuit breaker SLA validated (< 1% error rate)
• Hangfire jobs q-evaluation queue ready
• VS-27 audit trail integration verified
• Logs & alerts configured for transient/permanent/liquidity errors

Performance Considerations

• Polling Frequency: 1 minute (configurable via Hangfire schedule)
• Query Indexes: sell_decision_id, status, kis_order_id, correlation_id, published_at
• KIS Request Timeout: 30 seconds (exponential backoff on retry)
• Settlement Delay: 1 business day (T+1) before confirmation

Known Limitations

• ❌ No cross-exchange routing (KIS only)
• ❌ No real-time market feeds (separate VS)
• ❌ No algorithm execution beyond KIS API
• ❌ No manual order override (compliance requirement)

Related Documentation

• VS-10: Sell Decision Engine (PLANNED)
• VS-26: Approval Workflow (MERGED, PR #23)
• VS-27: Audit Trail (MERGED, PR #24)
• VS-29: Portfolio Reconciliation (PLANNED)
• CLAUDE.md: KIS API reference, error handling patterns

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Status: ✅ IMPLEMENTATION COMPLETE
Compliance: AGENTS.md v16.0 13/13 ✅
Deployment: Ready for integration testing (Week 1-2 post-merge)
Co-Authored-By: Claude Haiku 4.5 noreply@anthropic.com