Merge pull request #1648 from ranaroussi/hotfix/tkr-tz-already-in-cache

Fix multithread error 'tz already in cache'

tests/utils.py

@@ -0,0 +1,51 @@
+"""
+Tests for utils
+
+To run all tests in suite from commandline:
+   python -m unittest tests.utils
+
+Specific test class:
+   python -m unittest tests.utils.TestTicker
+
+"""
+# import pandas as pd
+# import numpy as np
+
+from .context import yfinance as yf
+from .context import session_gbl
+
+import unittest
+# import requests_cache
+import tempfile
+
+
+class TestUtils(unittest.TestCase):
+    session = None
+
+    @classmethod
+    def setUpClass(cls):
+        cls.tempCacheDir = tempfile.TemporaryDirectory()
+        yf.set_tz_cache_location(cls.tempCacheDir.name)
+
+    @classmethod
+    def tearDownClass(cls):
+        cls.tempCacheDir.cleanup()
+
+    def test_storeTzNoRaise(self):
+        # storing TZ to cache should never raise exception
+        tkr = 'AMZN'
+        tz1 = "America/New_York"
+        tz2 = "London/Europe"
+        cache = yf.utils.get_tz_cache()
+        cache.store(tkr, tz1)
+        cache.store(tkr, tz2)
+
+
+def suite():
+    suite = unittest.TestSuite()
+    suite.addTest(TestUtils('Test utils'))
+    return suite
+
+
+if __name__ == '__main__':
+    unittest.main()

yfinance/utils.py

@@ -980,10 +980,14 @@ class _TzCache:
     def store(self, tkr, tz):
         if tz is None:
             self.tz_db.delete(tkr)
-        elif self.tz_db.get(tkr) is not None:
-            raise Exception("Tkr {} tz already in cache".format(tkr))
         else:
-            self.tz_db.set(tkr, tz)
+            tz_db = self.tz_db.get(tkr)
+            if tz_db is not None:
+                if tz != tz_db:
+                    get_yf_logger().debug(f'{tkr}: Overwriting cached TZ "{tz_db}" with different TZ "{tz}"')
+                    self.tz_db.set(tkr, tz)
+            else:
+                self.tz_db.set(tkr, tz)
 
     @property
     def _db_dir(self):