Update app/app.py

app/app.py

@@ -1,8 +1,9 @@
 """
-Sentinel Arbitrage Engine - v13.0 OMEGA (File-Based & Unbreakable)
+Sentinel Arbitrage Engine - v13.1 FINAL (UI Fix)
 
 This version uses a file-based log for absolute signal persistence and
 a high-frequency polling mechanism for guaranteed data delivery.
+It includes the corrected HTML rendering for a professional UI.
 """
 import asyncio
 import os
@@ -15,7 +16,6 @@ from fastapi import FastAPI, Request
 from fastapi.responses import FileResponse, HTMLResponse
 from fastapi.staticfiles import StaticFiles
 
-# --- RELATIVE IMPORTS ---
 from .price_fetcher import PriceFetcher
 from .arbitrage_analyzer import ArbitrageAnalyzer
 
@@ -24,7 +24,6 @@ SIGNALS_FILE = "signals.json"
 
 @asynccontextmanager
 async def lifespan(app: FastAPI):
-    # Clear the log on startup
     if os.path.exists(SIGNALS_FILE):
         os.remove(SIGNALS_FILE)
     
@@ -36,7 +35,7 @@ async def lifespan(app: FastAPI):
             run_arbitrage_detector(app.state.price_fetcher, app.state.arbitrage_analyzer)
         )
         
-        print("🚀 Sentinel Arbitrage Engine v13.0 (File-Based) started.")
+        print("🚀 Sentinel Arbitrage Engine v13.1 (UI Fix) started.")
         yield
         
         print("⏳ Shutting down engine...")
@@ -45,7 +44,6 @@ async def lifespan(app: FastAPI):
         except asyncio.CancelledError: print("Engine shut down gracefully.")
 
 async def run_arbitrage_detector(price_fetcher, analyzer):
-    """The core engine loop. Detects opportunities and writes them to a file."""
     while True:
         try:
             await price_fetcher.update_prices_async()
@@ -65,17 +63,17 @@ async def run_arbitrage_detector(price_fetcher, analyzer):
                         briefing = await analyzer.get_alpha_briefing(asset, opportunity)
                         if briefing:
                             signal = {**opportunity, **briefing, "timestamp": datetime.now(timezone.utc).isoformat()}
-                            
-                            # --- THE FIX: Write signal directly to the JSON file ---
                             try:
-                                with open(SIGNALS_FILE, 'r+') as f:
-                                    data = json.load(f)
-                                    data.insert(0, signal) # Prepend new signal
-                                    f.seek(0)
-                                    json.dump(data, f, indent=4)
+                                data = []
+                                if os.path.exists(SIGNALS_FILE):
+                                    with open(SIGNALS_FILE, 'r') as f:
+                                        data = json.load(f)
+                                data.insert(0, signal)
+                                with open(SIGNALS_FILE, 'w') as f:
+                                    json.dump(data, f)
                             except (FileNotFoundError, json.JSONDecodeError):
                                 with open(SIGNALS_FILE, 'w') as f:
-                                    json.dump([signal], f, indent=4)
+                                    json.dump([signal], f)
                             
                             print(f"✅ Signal LOGGED for {asset}: {signal['spread_pct']:.3f}%")
         except Exception as e:
@@ -83,13 +81,39 @@ async def run_arbitrage_detector(price_fetcher, analyzer):
 
         await asyncio.sleep(15)
 
-# --- FastAPI App Setup ---
 app = FastAPI(lifespan=lifespan)
 
-# --- API Endpoints ---
+# ====================================================================
+#                       THE CRITICAL FIX IS HERE
+# ====================================================================
+def render_signal_card(signal: dict) -> str:
+    """Renders a single signal dictionary into a clean HTML table row."""
+    s = signal
+    time_str = datetime.fromisoformat(s['timestamp']).strftime('%H:%M:%S')
+    
+    # Determine which price is higher/lower for coloring
+    is_pyth_cheaper = s['pyth_price'] < s['chainlink_price']
+    
+    pyth_price_html = f'<span class="{"buy" if is_pyth_cheaper else "sell"}">${s["pyth_price"]:,.2f}</span>'
+    chainlink_price_html = f'<span class="{"sell" if is_pyth_cheaper else "buy"}">${s["chainlink_price"]:,.2f}</span>'
+
+    # Build the complete table row with 7 cells
+    return f"""
+    <tr>
+        <td>{time_str}</td>
+        <td><strong>{s['asset']}/USD</strong></td>
+        <td>{pyth_price_html}</td>
+        <td>{chainlink_price_html}</td>
+        <td><strong class="buy">{s['spread_pct']:.3f}%</strong></td>
+        <td><span class="risk-{s.get('risk', 'low').lower()}">{s.get('risk', 'N/A')}</span></td>
+        <td>{s.get('strategy', 'N/A')}</td>
+    </tr>
+    """
+# ====================================================================
+
 @app.get("/api/signals", response_class=HTMLResponse)
 async def get_signals_table(request: Request):
-    """Reads the signals file and renders the table body."""
+    """Reads the signals file and renders the entire table body."""
     try:
         with open(SIGNALS_FILE, 'r') as f:
             signals = json.load(f)
@@ -97,34 +121,22 @@ async def get_signals_table(request: Request):
         signals = []
 
     if not signals:
-        return HTMLResponse('<tr id="placeholder-row"><td colspan="7" style="text-align:center;">Monitoring for arbitrage opportunities...</td></tr>')
+        return HTMLResponse('<tr><td colspan="7" style="text-align:center;">Monitoring for arbitrage opportunities...</td></tr>')
 
-    table_rows = []
+    # Generate all table rows
+    table_rows_html = "".join([render_signal_card(s) for s in signals])
+    
+    # Calculate total simulated profit
     total_profit = 0
     for s in signals:
-        pyth_class = "buy" if s['pyth_price'] < s['chainlink_price'] else "sell"
-        chainlink_class = "sell" if s['pyth_price'] < s['chainlink_price'] else "buy"
-        profit = (s['chainlink_price'] - s['pyth_price']) if pyth_class == 'buy' else (s['pyth_price'] - s['chainlink_price'])
-        profit_after_fees = profit * (1 - 0.002) # Assume 0.2% total fees
-        total_profit += profit_after_fees
+        profit = abs(s['chainlink_price'] - s['pyth_price'])
+        total_profit += profit * (1 - 0.002) # Assume 0.2% total fees
 
-        table_rows.append(f"""
-        <tr>
-            <td>{datetime.fromisoformat(s['timestamp']).strftime('%H:%M:%S')}</td>
-            <td><strong>{s['asset']}/USD</strong></td>
-            <td><span class="{pyth_class}">Pyth</span><br>${s['pyth_price']:,.2f}</td>
-            <td><span class="{chainlink_class}">Agg.</span><br>${s['chainlink_price']:,.2f}</td>
-            <td><strong>{s['spread_pct']:.3f}%</strong></td>
-            <td><span class="risk-{s.get('risk', 'low').lower()}">{s.get('risk', 'N/A')}</span></td>
-            <td>{s.get('strategy', 'N/A')}</td>
-        </tr>
-        """)
-    
-    # Use OOB swap to update the P/L ticker
+    # Create the P/L ticker with an OOB swap attribute
     profit_html = f'<span id="pnl-ticker" hx-swap-oob="true">Simulated P/L: <span style="color: #34D399;">${total_profit:,.2f}</span></span>'
 
-    return HTMLResponse(profit_html + "".join(table_rows))
-
+    # Return the P/L ticker and the table rows together
+    return HTMLResponse(profit_html + table_rows_html)
 
-# Serve the static files (like index.html) from the 'static' directory
+# Serve the static files (like index.html)
 app.mount("/", StaticFiles(directory="static", html=True), name="static")