Improve logging behaviour, particulary download()

- Use same logger across all files
- download():
  - write tracebacks to DEBUG
  - deprecate 'show_errors' argument

yfinance/base.py

@@ -21,7 +21,6 @@
 
 from __future__ import print_function
 
-import logging
 import warnings
 import time as _time
 import datetime as _datetime
@@ -49,7 +48,7 @@ _BASE_URL_ = 'https://query2.finance.yahoo.com'
 _SCRAPE_URL_ = 'https://finance.yahoo.com/quote'
 _ROOT_URL_ = 'https://finance.yahoo.com'
 
-logger = logging.getLogger(__name__)
+logger = utils.get_yf_logger()
 
 class TickerBase:
     def __init__(self, ticker, session=None):
@@ -145,10 +144,10 @@ class TickerBase:
         if debug is not None:
             if debug:
                 utils.print_once(f"yfinance: Ticker.history(debug={debug}) argument is deprecated and will be removed in future version. Do this instead: logging.getLogger('yfinance').setLevel(logging.ERROR)")
-                logging.getLogger('yfinance').setLevel(logging.ERROR)
+                logger.setLevel(logging.ERROR)
             else:
                 utils.print_once(f"yfinance: Ticker.history(debug={debug}) argument is deprecated and will be removed in future version. Do this instead to suppress error messages: logging.getLogger('yfinance').setLevel(logging.CRITICAL)")
-                logging.getLogger('yfinance').setLevel(logging.CRITICAL)
+                logger.setLevel(logging.CRITICAL)
 
         if start or period is None or period.lower() == "max":
             # Check can get TZ. Fail => probably delisted

yfinance/data.py

@@ -26,9 +26,11 @@ try:
 except ImportError:
     import json as json
 
+from . import utils
+
 cache_maxsize = 64
 
-logger = logging.getLogger(__name__)
+logger = utils.get_yf_logger()
 
 
 def lru_cache_freezeargs(func):

yfinance/multi.py

@@ -30,11 +30,9 @@ import pandas as _pd
 from . import Ticker, utils
 from . import shared
 
-logger = logging.getLogger(__name__)
-
 def download(tickers, start=None, end=None, actions=False, threads=True, ignore_tz=None,
              group_by='column', auto_adjust=False, back_adjust=False, repair=False, keepna=False,
-             progress=True, period="max", show_errors=True, interval="1d", prepost=False,
+             progress=True, period="max", show_errors=None, interval="1d", prepost=False,
              proxy=None, rounding=False, timeout=10):
     """Download yahoo tickers
     :Parameters:
@@ -80,11 +78,20 @@ def download(tickers, start=None, end=None, actions=False, threads=True, ignore_
             Optional. Round values to 2 decimal places?
         show_errors: bool
             Optional. Doesn't print errors if False
+            DEPRECATED, will be removed in future version
         timeout: None or float
             If not None stops waiting for a response after given number of
             seconds. (Can also be a fraction of a second e.g. 0.01)
     """
 
+    if show_errors is not None:
+        if show_errors:
+            utils.print_once(f"yfinance: download(show_errors={show_errors}) argument is deprecated and will be removed in future version. Do this instead: logging.getLogger('yfinance').setLevel(logging.ERROR)")
+            logging.getLogger('yfinance').setLevel(logging.ERROR)
+        else:
+            utils.print_once(f"yfinance: download(show_errors={show_errors}) argument is deprecated and will be removed in future version. Do this instead to suppress error messages: logging.getLogger('yfinance').setLevel(logging.CRITICAL)")
+            logging.getLogger('yfinance').setLevel(logging.CRITICAL)
+
     if ignore_tz is None:
         # Set default value depending on interval
         if interval[1:] in ['m', 'h']:
@@ -117,11 +124,7 @@ def download(tickers, start=None, end=None, actions=False, threads=True, ignore_
     # reset shared._DFS
     shared._DFS = {}
     shared._ERRORS = {}
-
-    # temporarily disable error reporting while downloading
-    yf_logger = logging.getLogger('yfinance')
-    yf_lvl = yf_logger.level
-    yf_logger.setLevel(logging.CRITICAL)
+    shared._TRACEBACKS = {}
 
     # download using threads
     if threads:
@@ -154,19 +157,13 @@ def download(tickers, start=None, end=None, actions=False, threads=True, ignore_
     if progress:
         shared._PROGRESS_BAR.completed()
 
-    # restore error reporting
-    yf_logger.setLevel(yf_lvl)
-
     if shared._ERRORS:
-        if show_errors:
-            print('\n%.f Failed download%s:' % (
-                len(shared._ERRORS), 's' if len(shared._ERRORS) > 1 else ''))
-            # print(shared._ERRORS)
-            print("\n".join(['- %s: %s' %
-                             v for v in list(shared._ERRORS.items())]))
-        else:
-            logger.error('%d failed downloads: %s',
-                         len(shared._ERRORS), shared._ERRORS)
+        logger = utils.get_yf_logger()
+        logger.error('\n%.f Failed download%s:' % (
+            len(shared._ERRORS), 's' if len(shared._ERRORS) > 1 else ''))
+        for ticker in shared._ERRORS:
+            logger.error(f'- {ticker}: {shared._ERRORS[ticker]}')
+            logger.debug(f'{ticker}: ' + shared._TRACEBACKS[ticker])
 
     if ignore_tz:
         for tkr in shared._DFS.keys():
@@ -230,8 +227,9 @@ def _download_one_threaded(ticker, start=None, end=None,
                              keepna, timeout)
     except Exception as e:
         # glob try/except needed as current thead implementation breaks if exception is raised.
+        shared._TRACEBACKS[ticker] = traceback.format_exc()
         shared._DFS[ticker] = utils.empty_df()
-        shared._ERRORS[ticker] = traceback.format_exc()
+        shared._ERRORS[ticker] = repr(e)
     else:
         shared._DFS[ticker.upper()] = data
     if progress:

yfinance/scrapers/fundamentals.py

@@ -9,7 +9,7 @@ from yfinance import utils
 from yfinance.data import TickerData
 from yfinance.exceptions import YFinanceDataException, YFinanceException
 
-logger = logging.getLogger(__name__)
+logger = utils.get_yf_logger()
 
 class Fundamentals:
 

yfinance/scrapers/quote.py

@@ -8,7 +8,7 @@ import pandas as pd
 from yfinance import utils
 from yfinance.data import TickerData
 
-logger = logging.getLogger(__name__)
+logger = utils.get_yf_logger()
 
 info_retired_keys_price = {"currentPrice", "dayHigh", "dayLow", "open", "previousClose", "volume", "volume24Hr"}
 info_retired_keys_price.update({"regularMarket"+s for s in ["DayHigh", "DayLow", "Open", "PreviousClose", "Price", "Volume"]})

yfinance/shared.py

@@ -22,4 +22,5 @@
 _DFS = {}
 _PROGRESS_BAR = None
 _ERRORS = {}
+_TRACEBACKS = {}
 _ISINS = {}

yfinance/utils.py

@@ -36,6 +36,7 @@ import appdirs as _ad
 import sqlite3 as _sqlite3
 import atexit as _atexit
 from functools import lru_cache
+import logging
 
 from threading import Lock
 
@@ -69,6 +70,17 @@ def print_once(msg):
     print(msg)
 
 
+yf_logger = None
+def get_yf_logger():
+    global yf_logger
+    if yf_logger is None:
+        yf_logger = logging.getLogger("yfinance")
+        if yf_logger.handlers is None or len(yf_logger.handlers) == 0:
+            # Only add basic stream handler is user not already added one
+            yf_logger.addHandler(logging.StreamHandler())
+    return yf_logger
+
+
 def is_isin(string):
     return bool(_re.match("^([A-Z]{2})([A-Z0-9]{9})([0-9]{1})$", string))