Reduce Errors #2

src/InternetStatusReporter.py

@@ -114,13 +114,14 @@ def measure_latency(self):
     from json import dumps
     from sys import exc_info
     from tcp_latency import measure_latency
-    from src.utils import calculate_standard_deviation
+    from src.utils import calculate_standard_deviation, remove_none
 
     results = {}
     for latency_address in self.latency_addresses:
       try:
         runs = int(getenv('LATENCY_RUNS'))
         data = measure_latency(host=latency_address, port=80, runs=runs, timeout=2.5)
+        data = remove_none(data)
         mean, deviation = calculate_standard_deviation(data, self.logger)
       except:
         self.logger.exception(f'Unexpected error: {exc_info()[0]}')

src/tests/utils_test.py

@@ -24,16 +24,16 @@ def test_calculate_standard_deviation_when_an_array_of_numbers_is_passed(self, m
     )
 
   @patch('logging.Logger')
-  def test_calculate_standard_deviation_when_an_array_of_numbers_and_none_is_passed(self, mock_logger):
+  def test_calculate_standard_deviation_when_an_array_of_one_number_is_passed(self, mock_logger):
     self.assertEqual(
-      calculate_standard_deviation([None,1.0,2,3,None,4.0,5], mock_logger),
-      (3.0, 1.5811388300841898)
+      calculate_standard_deviation([1.0], mock_logger),
+      (1.0, 0)
     )
 
   @patch('logging.Logger')
-  def test_calculate_standard_deviation_when_an_array_of_none_is_passed(self, mock_logger):
+  def test_calculate_standard_deviation_when_an_empty_array_is_passed(self, mock_logger):
     self.assertEqual(
-      calculate_standard_deviation([None, None, None, None], mock_logger),
+      calculate_standard_deviation([], mock_logger),
       None
     )
 

src/utils.py

@@ -15,11 +15,12 @@ def calculate_standard_deviation(data, logger):
   from math import sqrt
   from sys import exc_info
 
-  data = remove_none(data)
   length = len(data)
 
   if length == 0:
     return
+  elif length == 1:
+    return data[0], 0
 
   try:
     mean = reduce(lambda a,b: a+b, data)/length