chore: Update conf retrieval docstring and adjust pool_size (#39721)

Signed-off-by: Kacper Muda <mudakacper@gmail.com>

airflow/providers/openlineage/conf.py

@@ -14,6 +14,19 @@
 # KIND, either express or implied.  See the License for the
 # specific language governing permissions and limitations
 # under the License.
+"""
+This module provides functions for safely retrieving and handling OpenLineage configurations.
+
+To prevent errors caused by invalid user-provided configuration values, we use ``conf.get()``
+to fetch values as strings and perform safe conversions using custom functions.
+
+Any invalid configuration values should be treated as incorrect and replaced with default values.
+For example, if the default for boolean ``custom_ol_var`` is False, any non-true value provided:
+``"asdf"``, ``12345``, ``{"key": 1}`` or empty string, will result in False being used.
+
+By using default values for invalid configuration values, we ensure that the configurations are handled
+safely, preventing potential runtime errors due to conversion issues.
+"""
 
 from __future__ import annotations
 
@@ -30,6 +43,13 @@ def _is_true(arg: Any) -> bool:
     return str(arg).lower().strip() in ("true", "1", "t")
 
 
+def _safe_int_convert(arg: Any, default: int) -> int:
+    try:
+        return int(arg)
+    except (ValueError, TypeError):
+        return default
+
+
 @cache
 def config_path(check_legacy_env_var: bool = True) -> str:
     """[openlineage] config_path."""
@@ -108,5 +128,5 @@ def is_disabled() -> bool:
 @cache
 def dag_state_change_process_pool_size() -> int:
     """[openlineage] dag_state_change_process_pool_size."""
-    option = conf.getint(_CONFIG_SECTION, "dag_state_change_process_pool_size", fallback=1)
-    return option
+    option = conf.get(_CONFIG_SECTION, "dag_state_change_process_pool_size", fallback="")
+    return _safe_int_convert(str(option).strip(), default=1)

tests/providers/openlineage/test_conf.py

@@ -23,8 +23,10 @@
 
 from airflow.providers.openlineage.conf import (
     _is_true,
+    _safe_int_convert,
     config_path,
     custom_extractors,
+    dag_state_change_process_pool_size,
     disabled_operators,
     is_disabled,
     is_source_enabled,
@@ -49,6 +51,7 @@
 _CONFIG_OPTION_DISABLED = "disabled"
 _VAR_URL = "OPENLINEAGE_URL"
 _CONFIG_OPTION_SELECTIVE_ENABLE = "selective_enable"
+_CONFIG_OPTION_DAG_STATE_CHANGE_PROCESS_POOL_SIZE = "dag_state_change_process_pool_size"
 
 _BOOL_PARAMS = (
     ("1", True),
@@ -76,6 +79,7 @@ def clear_cache():
     transport.cache_clear()
     is_disabled.cache_clear()
     selective_enable.cache_clear()
+    dag_state_change_process_pool_size.cache_clear()
     try:
         yield
     finally:
@@ -87,6 +91,7 @@ def clear_cache():
         transport.cache_clear()
         is_disabled.cache_clear()
         selective_enable.cache_clear()
+        dag_state_change_process_pool_size.cache_clear()
 
 
 @pytest.mark.parametrize(
@@ -103,6 +108,35 @@ def test_is_true(var_string, expected):
     assert _is_true(var_string) is expected
 
 
+@pytest.mark.parametrize(
+    "input_value, expected",
+    [
+        ("123", 123),
+        (456, 456),
+        ("789", 789),
+        (0, 0),
+        ("0", 0),
+    ],
+)
+def test_safe_int_convert(input_value, expected):
+    assert _safe_int_convert(input_value, default=1) == expected
+
+
+@pytest.mark.parametrize(
+    "input_value, default",
+    [
+        ("abc", 1),
+        ("", 2),
+        (None, 3),
+        ("123abc", 4),
+        ([], 5),
+        ("1.2", 6),
+    ],
+)
+def test_safe_int_convert_erroneous_values(input_value, default):
+    assert _safe_int_convert(input_value, default) == default
+
+
 @env_vars({_VAR_CONFIG_PATH: "env_var_path"})
 @conf_vars({(_CONFIG_SECTION, _CONFIG_OPTION_CONFIG_PATH): None})
 def test_config_path_legacy_env_var_is_used_when_no_conf_option_set():
@@ -456,3 +490,25 @@ def test_is_disabled_empty_conf_option():
 )
 def test_is_disabled_do_not_fail_if_conf_option_missing():
     assert is_disabled() is True
+
+
+@pytest.mark.parametrize(
+    ("var_string", "expected"),
+    (
+        ("1", 1),
+        ("2   ", 2),
+        ("  3", 3),
+        ("4.56", 1),  # default
+        ("asdf", 1),  # default
+        ("true", 1),  # default
+        ("false", 1),  # default
+        ("None", 1),  # default
+        ("", 1),  # default
+        (" ", 1),  # default
+        (None, 1),  # default
+    ),
+)
+def test_dag_state_change_process_pool_size(var_string, expected):
+    with conf_vars({(_CONFIG_SECTION, _CONFIG_OPTION_DAG_STATE_CHANGE_PROCESS_POOL_SIZE): var_string}):
+        result = dag_state_change_process_pool_size()
+        assert result == expected