feat: dashboard background thread with CLI flag (issue #97)

Add --dashboard CLI flag and DASHBOARD_ENABLED env var to start
FastAPI dashboard in a daemon thread alongside the trading loop.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

pyproject.toml

@@ -10,6 +10,7 @@ dependencies = [
     "google-genai>=1.0,<2",
     "scipy>=1.11,<2",
     "fastapi>=0.110,<1",
+    "uvicorn>=0.29,<1",
 ]
 
 [project.optional-dependencies]

src/config.py

@@ -83,6 +83,11 @@ class Settings(BaseSettings):
     TELEGRAM_COMMANDS_ENABLED: bool = True
     TELEGRAM_POLLING_INTERVAL: float = 1.0  # seconds
 
+    # Dashboard (optional)
+    DASHBOARD_ENABLED: bool = False
+    DASHBOARD_HOST: str = "127.0.0.1"
+    DASHBOARD_PORT: int = Field(default=8080, ge=1, le=65535)
+
     model_config = {"env_file": ".env", "env_file_encoding": "utf-8"}
 
     @property

src/main.py

@@ -10,6 +10,7 @@ import argparse
 import asyncio
 import logging
 import signal
+import threading
 from datetime import UTC, datetime
 from typing import Any
 
@@ -844,6 +845,48 @@ async def _run_evolution_loop(
         logger.warning("Evolution notification failed on %s: %s", market_date, exc)
 
 
+def _start_dashboard_server(settings: Settings) -> threading.Thread | None:
+    """Start FastAPI dashboard in a daemon thread when enabled."""
+    if not settings.DASHBOARD_ENABLED:
+        return None
+
+    def _serve() -> None:
+        try:
+            import uvicorn
+
+            from src.dashboard import create_dashboard_app
+
+            app = create_dashboard_app(settings.DB_PATH)
+            uvicorn.run(
+                app,
+                host=settings.DASHBOARD_HOST,
+                port=settings.DASHBOARD_PORT,
+                log_level="info",
+            )
+        except Exception as exc:
+            logger.warning("Dashboard server failed to start: %s", exc)
+
+    thread = threading.Thread(
+        target=_serve,
+        name="dashboard-server",
+        daemon=True,
+    )
+    thread.start()
+    logger.info(
+        "Dashboard server started at http://%s:%d",
+        settings.DASHBOARD_HOST,
+        settings.DASHBOARD_PORT,
+    )
+    return thread
+
+
+def _apply_dashboard_flag(settings: Settings, dashboard_flag: bool) -> Settings:
+    """Apply CLI dashboard flag over environment settings."""
+    if dashboard_flag and not settings.DASHBOARD_ENABLED:
+        return settings.model_copy(update={"DASHBOARD_ENABLED": True})
+    return settings
+
+
 async def run(settings: Settings) -> None:
     """Main async loop — iterate over open markets on a timer."""
     broker = KISBroker(settings)
@@ -1042,6 +1085,7 @@ async def run(settings: Settings) -> None:
         low_volatility_threshold=30.0,
     )
     priority_queue = PriorityTaskQueue(max_size=1000)
+    _start_dashboard_server(settings)
 
     # Track last scan time for each market
     last_scan_time: dict[str, float] = {}
@@ -1395,10 +1439,16 @@ def main() -> None:
         default="paper",
         help="Trading mode (default: paper)",
     )
+    parser.add_argument(
+        "--dashboard",
+        action="store_true",
+        help="Enable FastAPI dashboard server in background thread",
+    )
     args = parser.parse_args()
 
     setup_logging()
     settings = Settings(MODE=args.mode)  # type: ignore[call-arg]
+    settings = _apply_dashboard_flag(settings, args.dashboard)
     asyncio.run(run(settings))
 
 

tests/test_main.py

@@ -5,6 +5,7 @@ from unittest.mock import ANY, AsyncMock, MagicMock, patch
 
 import pytest
 
+from src.config import Settings
 from src.context.layer import ContextLayer
 from src.context.scheduler import ScheduleResult
 from src.core.risk_manager import CircuitBreakerTripped, FatFingerRejected
@@ -12,9 +13,11 @@ from src.db import init_db, log_trade
 from src.evolution.scorecard import DailyScorecard
 from src.logging.decision_logger import DecisionLogger
 from src.main import (
+    _apply_dashboard_flag,
     _handle_market_close,
     _run_context_scheduler,
     _run_evolution_loop,
+    _start_dashboard_server,
     safe_float,
     trading_cycle,
 )
@@ -1454,3 +1457,44 @@ async def test_run_evolution_loop_notification_error_is_ignored() -> None:
 
     optimizer.evolve.assert_called_once()
     telegram.send_message.assert_called_once()
+
+
+def test_apply_dashboard_flag_enables_dashboard() -> None:
+    settings = Settings(
+        KIS_APP_KEY="test_key",
+        KIS_APP_SECRET="test_secret",
+        KIS_ACCOUNT_NO="12345678-01",
+        GEMINI_API_KEY="test_gemini_key",
+        DASHBOARD_ENABLED=False,
+    )
+    updated = _apply_dashboard_flag(settings, dashboard_flag=True)
+    assert updated.DASHBOARD_ENABLED is True
+
+
+def test_start_dashboard_server_disabled_returns_none() -> None:
+    settings = Settings(
+        KIS_APP_KEY="test_key",
+        KIS_APP_SECRET="test_secret",
+        KIS_ACCOUNT_NO="12345678-01",
+        GEMINI_API_KEY="test_gemini_key",
+        DASHBOARD_ENABLED=False,
+    )
+    thread = _start_dashboard_server(settings)
+    assert thread is None
+
+
+def test_start_dashboard_server_enabled_starts_thread() -> None:
+    settings = Settings(
+        KIS_APP_KEY="test_key",
+        KIS_APP_SECRET="test_secret",
+        KIS_ACCOUNT_NO="12345678-01",
+        GEMINI_API_KEY="test_gemini_key",
+        DASHBOARD_ENABLED=True,
+    )
+    mock_thread = MagicMock()
+    with patch("src.main.threading.Thread", return_value=mock_thread) as mock_thread_cls:
+        thread = _start_dashboard_server(settings)
+
+    assert thread == mock_thread
+    mock_thread_cls.assert_called_once()
+    mock_thread.start.assert_called_once()