Fix yfinance rate limit and session compatibility in dataflows/y_finance.py

cli/main.py

@@ -462,7 +462,7 @@ def update_display(layout, spinner_text=None, stats_handler=None, start_time=Non
 def get_user_selections():
     """Get all user selections before starting the analysis display."""
     # Display ASCII art welcome message
-    with open("./cli/static/welcome.txt", "r") as f:
+    with open("./cli/static/welcome.txt", "r", encoding='utf-8') as f:
         welcome_ascii = f.read()
 
     # Create welcome box content
@@ -948,7 +948,7 @@ def run_analysis():
             func(*args, **kwargs)
             timestamp, message_type, content = obj.messages[-1]
             content = content.replace("\n", " ")  # Replace newlines with spaces
-            with open(log_file, "a") as f:
+            with open(log_file, "a", encoding='utf-8') as f:
                 f.write(f"{timestamp} [{message_type}] {content}\n")
         return wrapper
     
@@ -959,7 +959,7 @@ def run_analysis():
             func(*args, **kwargs)
             timestamp, tool_name, args = obj.tool_calls[-1]
             args_str = ", ".join(f"{k}={v}" for k, v in args.items())
-            with open(log_file, "a") as f:
+            with open(log_file, "a", encoding='utf-8') as f:
                 f.write(f"{timestamp} [Tool Call] {tool_name}({args_str})\n")
         return wrapper
 
@@ -972,7 +972,7 @@ def run_analysis():
                 content = obj.report_sections[section_name]
                 if content:
                     file_name = f"{section_name}.md"
-                    with open(report_dir / file_name, "w") as f:
+                    with open(report_dir / file_name, "w", encoding='utf-8') as f:
                         f.write(content)
         return wrapper
 

tradingagents/dataflows/y_finance.py

@@ -1,51 +1,104 @@
 from typing import Annotated
 from datetime import datetime
 from dateutil.relativedelta import relativedelta
+import time
+from yfinance.exceptions import YFRateLimitError
+import requests
 import yfinance as yf
 import os
 from .stockstats_utils import StockstatsUtils
 
-def get_YFin_data_online(
+import pandas as pd  # for polygon data processing
+from polygon import RESTClient  # for polygon client (need to pip install polygon-api-client)
+
+# Polygon API Key: free registration https://polygon.io/ (free layer 5min/day enough)
+POLYGON_API_KEY = "your key"  # replace with your key
+
+def get_YFin_data_online(  # rename? or keep, add fallback inside
     symbol: Annotated[str, "ticker symbol of the company"],
     start_date: Annotated[str, "Start date in yyyy-mm-dd format"],
     end_date: Annotated[str, "End date in yyyy-mm-dd format"],
+    max_retries: int = 5,
+    base_delay: float = 2.0,
 ):
+    """
+    original yfinance + Polygon fallback: yfinance rate limit automatically switch to Polygon.
+    """
+    # date validation
+    try:
+        datetime.strptime(start_date, "%Y-%m-%d")
+        datetime.strptime(end_date, "%Y-%m-%d")
+    except ValueError:
+        raise ValueError("date format must be YYYY-MM-DD")
 
-    datetime.strptime(start_date, "%Y-%m-%d")
-    datetime.strptime(end_date, "%Y-%m-%d")
+    time.sleep(1.0)  # prevent concurrency
 
-    # Create ticker object
-    ticker = yf.Ticker(symbol.upper())
+    # first try yfinance
+    for attempt in range(max_retries):
+        try:
+            ticker = yf.Ticker(symbol.upper())
+            data = ticker.history(start=start_date, end=end_date)
+            if not data.empty:
+                return _format_data_to_csv(data, symbol, start_date, end_date)  # extract formatting function
+            else:
+                print("yfinance returned empty data, trying Polygon...")
+                break  # 空数据也fallback
+        except YFRateLimitError:
+            if attempt == max_retries - 1:
+                print("yfinance all failed, switching to Polygon...")
+                break
+            wait_time = base_delay * (2 ** attempt)
+            print(f"⚠️ Yahoo rate limit, waiting {wait_time:.0f} seconds... ({attempt+1}/{max_retries})")
+            time.sleep(wait_time)
+        except Exception as e:
+            print(f"yfinance other error: {e}")
+            if attempt == max_retries - 1:
+                break
+            time.sleep(base_delay)
 
-    # Fetch historical data for the specified date range
-    data = ticker.history(start=start_date, end=end_date)
-
-    # Check if data is empty
-    if data.empty:
-        return (
-            f"No data found for symbol '{symbol}' between {start_date} and {end_date}"
+    # Fallback: use Polygon to pull data (stable, free layer enough)
+    try:
+        client = RESTClient(api_key=POLYGON_API_KEY)
+        aggs = client.get_aggs(
+            ticker=symbol.upper(),
+            multiplier=1,  # 1天
+            timespan="day",
+            from_=start_date,
+            to=end_date,
         )
+        if aggs:
+            df = pd.DataFrame([{
+                'Date': pd.to_datetime(agg.timestamp, unit='ms').date(),
+                'Open': agg.open,
+                'High': agg.high,
+                'Low': agg.low,
+                'Close': agg.close,
+                'Volume': agg.volume,
+            } for agg in aggs])
+            df.set_index('Date', inplace=True)
+            df.sort_index(inplace=True)
+            return _format_data_to_csv(df, symbol, start_date, end_date)
+        else:
+            return f"No data from Polygon for '{symbol}' between {start_date} and {end_date}"
+    except Exception as e:
+        return f"Polygon fallback failed: {str(e)}. Please check API Key."
 
-    # Remove timezone info from index for cleaner output
+def _format_data_to_csv(data, symbol, start_date, end_date):
+    """统一格式化输出"""
+    """standardize data output"""
     if data.index.tz is not None:
         data.index = data.index.tz_localize(None)
-
-    # Round numerical values to 2 decimal places for cleaner display
-    numeric_columns = ["Open", "High", "Low", "Close", "Adj Close"]
+    numeric_columns = ["Open", "High", "Low", "Close"]  # Adj Close Polygon has no, simplify
     for col in numeric_columns:
         if col in data.columns:
             data[col] = data[col].round(2)
-
-    # Convert DataFrame to CSV string
+    if "Adj Close" in data.columns:
+        data["Adj Close"] = data["Adj Close"].round(2)
     csv_string = data.to_csv()
-
-    # Add header information
     header = f"# Stock data for {symbol.upper()} from {start_date} to {end_date}\n"
     header += f"# Total records: {len(data)}\n"
     header += f"# Data retrieved on: {datetime.now().strftime('%Y-%m-%d %H:%M:%S')}\n\n"
-
     return header + csv_string
-
 def get_stock_stats_indicators_window(
     symbol: Annotated[str, "ticker symbol of the company"],
     indicator: Annotated[str, "technical indicator to get the analysis and report of"],