allow non-positive values in gettimedelta

Before this commit, gettimedelta method was preventing
user to provide non-positive values. Now it is totally up to
users to provide a sensible value for this configuration

airflow/config_templates/config.yml

@@ -363,7 +363,7 @@
       default: "downstream"
     - name: default_task_execution_timeout
       description: |
-        The default task execution_timeout value for the operators. Expected positive integer value to
+        The default task execution_timeout value for the operators. Expected an integer value to
         be passed into timedelta as seconds. If not specified, then the value is considered as None,
         meaning that the operators are never timed out by default.
       version_added: 2.3.0

airflow/config_templates/default_airflow.cfg

@@ -210,7 +210,7 @@ default_task_retries = 0
 # The weighting method used for the effective total priority weight of the task
 default_task_weight_rule = downstream
 
-# The default task execution_timeout value for the operators. Expected positive integer value to
+# The default task execution_timeout value for the operators. Expected an integer value to
 # be passed into timedelta as seconds. If not specified, then the value is considered as None,
 # meaning that the operators are never timed out by default.
 default_task_execution_timeout =

airflow/configuration.py

@@ -632,14 +632,6 @@ def gettimedelta(self, section, key, fallback=None, **kwargs) -> Optional[dateti
                     f'Current value: "{val}".'
                 )
 
-            # the given value must be positive.
-            if int_val <= 0:
-                raise AirflowConfigException(
-                    f'Failed to convert value to timedelta in `seconds`. '
-                    f'Value must be greater than zero. '
-                    f'Please check "{key}" key in "{section}" section. Current value: "{val}".'
-                )
-
             try:
                 return datetime.timedelta(seconds=int_val)
             except OverflowError as err:

tests/core/test_configuration.py

@@ -851,14 +851,14 @@ def test_gettimedelta(self):
 # too large value for C int
 key3 = 999999999999999
 
-# Equals to None
+[valid]
+# negative value
 key4 = -1
 
 # zero
 key5 = 0
 
-[valid]
-# valid seconds
+# positive value
 key6 = 300
 
 [default]
@@ -894,26 +894,10 @@ def test_gettimedelta(self):
         ):
             test_conf.gettimedelta("invalid", "key3")
 
-        with pytest.raises(
-            AirflowConfigException,
-            match=re.escape(
-                'Failed to convert value to timedelta in `seconds`. '
-                'Value must be greater than zero. '
-                'Please check "key4" key in "invalid" section. Current value: "-1".'
-            ),
-        ):
-            test_conf.gettimedelta("invalid", "key4")
-
-        with pytest.raises(
-            AirflowConfigException,
-            match=re.escape(
-                'Failed to convert value to timedelta in `seconds`. '
-                'Value must be greater than zero. '
-                'Please check "key5" key in "invalid" section. Current value: "0".'
-            ),
-        ):
-            test_conf.gettimedelta("invalid", "key5")
-
+        assert isinstance(test_conf.gettimedelta('valid', 'key4'), datetime.timedelta)
+        assert test_conf.gettimedelta('valid', 'key4') == datetime.timedelta(seconds=-1)
+        assert isinstance(test_conf.gettimedelta('valid', 'key5'), datetime.timedelta)
+        assert test_conf.gettimedelta('valid', 'key5') == datetime.timedelta(seconds=0)
         assert isinstance(test_conf.gettimedelta('valid', 'key6'), datetime.timedelta)
         assert test_conf.gettimedelta('valid', 'key6') == datetime.timedelta(seconds=300)
         assert isinstance(test_conf.gettimedelta('default', 'key7'), type(None))