fix: simplify client version check

integrations/client/test_delphi_epidata.py

@@ -318,27 +318,14 @@ def json(self): return json.loads(self.content)
     get.reset_mock()
     get.return_value = MockJson(b'{"info": {"version": "0.0.1"}}', 200)
 
-    # "back up" the value of this private class var and replace w/ default
-    # so the ._version_check() method runs unencumbered:
-    e_vdc__save = Epidata._version_checked
-    Epidata._version_checked = False
-    # run version check:
     Epidata._version_check()
-    # "restore" class var:
-    Epidata._version_checked = e_vdc__save
 
     captured = self.capsys.readouterr()
     output = captured.err.splitlines()
     self.assertEqual(len(output), 1)
     self.assertIn("Client version not up to date", output[0])
     self.assertIn("\'latest_version\': \'0.0.1\'", output[0])
 
-  @patch('delphi.epidata.client.delphi_epidata.Epidata._version_check')
-  def test_version_check_once(self, version_check):
-    """Test that the _version_check() function is only called once on initial module import."""
-    from delphi.epidata.client.delphi_epidata import Epidata
-    version_check.assert_not_called()
-
   def test_geo_value(self):
     """test different variants of geo types: single, *, multi."""
 

src/client/delphi_epidata.py

@@ -46,25 +46,18 @@ class Epidata:
     debug = False # if True, prints extra logging statements
     sandbox = False # if True, will not execute any queries
 
-    _version_checked = False
-
     @staticmethod
     def log(evt, **kwargs):
         kwargs['event'] = evt
         kwargs['timestamp'] = time.strftime("%Y-%m-%d %H:%M:%S %z")
         return sys.stderr.write(str(kwargs) + "\n")
 
-    # Check that this client's version matches the most recent available.
-    # This is indended to run just once per program execution, on initial module load.
-    # See the bottom of this file for the ultimate call to this method.
+    # Check that this client's version matches the most recent available. This
+    # is run just once per program execution, on initial module load (see the
+    # bottom of the file). This is a function of how Python's module system
+    # works: https://docs.python.org/3/reference/import.html#the-module-cache
     @staticmethod
     def _version_check():
-        if Epidata._version_checked:
-            # already done; nothing to do!
-            return
-
-        Epidata._version_checked = True
-
         try:
             request = requests.get('https://pypi.org/pypi/delphi-epidata/json', timeout=5)
             latest_version = request.json()['info']['version']