Fix the default value for store_dag_code (apache#9554)

related to apache#8255 (fixes the issue mentioned with `store_dag_code` but does not address Config interpolation)

The default value of `store_dag_code` should be same as `store_serialized_dags` setting.  But if the value is set it should use that value

airflow/config_templates/config.yml

@@ -338,8 +338,8 @@
         ``store_serialized_dags`` setting.
       version_added: 1.10.10
       type: string
-      example: ~
-      default: "%(store_serialized_dags)s"
+      example: "False"
+      default: ~
     - name: max_num_rendered_ti_fields_per_task
       description: |
         Maximum number of Rendered Task Instance Fields (Template Fields) per task to store

airflow/config_templates/default_airflow.cfg

@@ -195,7 +195,8 @@ min_serialized_dag_update_interval = 30
 # If set to True, Webserver reads file contents from DB instead of
 # trying to access files in a DAG folder. Defaults to same as the
 # ``store_serialized_dags`` setting.
-store_dag_code = %(store_serialized_dags)s
+# Example: store_dag_code = False
+# store_dag_code =
 
 # Maximum number of Rendered Task Instance Fields (Template Fields) per task to store
 # in the Database.

airflow/models/dag.py

@@ -1589,7 +1589,7 @@ def bulk_sync_to_db(cls, dags: Collection["DAG"], sync_time=None, session=None):
                         orm_dag.tags.append(dag_tag_orm)
                         session.add(dag_tag_orm)
 
-        if conf.getboolean('core', 'store_dag_code', fallback=False):
+        if settings.STORE_DAG_CODE:
             DagCode.bulk_sync_to_db([dag.fileloc for dag in orm_dags])
 
         session.commit()

airflow/models/dagcode.py

@@ -22,9 +22,9 @@
 
 from sqlalchemy import BigInteger, Column, String, UnicodeText, and_, exists
 
-from airflow.configuration import conf
 from airflow.exceptions import AirflowException, DagCodeNotFound
 from airflow.models import Base
+from airflow.settings import STORE_DAG_CODE
 from airflow.utils import timezone
 from airflow.utils.file import correct_maybe_zipped, open_maybe_zipped
 from airflow.utils.session import provide_session
@@ -181,7 +181,7 @@ def code(cls, fileloc) -> str:
 
         :return: source code as string
         """
-        if conf.getboolean('core', 'store_dag_code', fallback=False):
+        if STORE_DAG_CODE:
             return cls._get_code_from_db(fileloc)
         else:
             return cls._get_code_from_file(fileloc)

airflow/settings.py

@@ -340,6 +340,11 @@ def initialize():
 MIN_SERIALIZED_DAG_UPDATE_INTERVAL = conf.getint(
     'core', 'min_serialized_dag_update_interval', fallback=30)
 
+# Whether to persist DAG files code in DB. If set to True, Webserver reads file contents
+# from DB instead of trying to access files in a DAG folder.
+# Defaults to same as the store_serialized_dags setting.
+STORE_DAG_CODE = conf.getboolean("core", "store_dag_code", fallback=STORE_SERIALIZED_DAGS)
+
 # If donot_modify_handlers=True, we do not modify logging handlers in task_run command
 # If the flag is set to False, we remove all handlers from the root logger
 # and add all handlers from 'airflow.task' logger to the root Logger. This is done

airflow/utils/dag_processing.py

@@ -41,7 +41,7 @@
 from airflow.exceptions import AirflowException
 from airflow.models import errors
 from airflow.models.taskinstance import SimpleTaskInstance, TaskInstance
-from airflow.settings import STORE_SERIALIZED_DAGS
+from airflow.settings import STORE_DAG_CODE, STORE_SERIALIZED_DAGS
 from airflow.stats import Stats
 from airflow.utils import timezone
 from airflow.utils.file import list_py_file_paths
@@ -631,7 +631,7 @@ def __init__(self,
             conf.getint('scheduler', 'scheduler_zombie_task_threshold'))
 
         # Should store dag file source in a database?
-        self.store_dag_code = conf.getboolean('core', 'store_dag_code', fallback=False)
+        self.store_dag_code = STORE_DAG_CODE
         # Map from file path to the processor
         self._processors: Dict[str, AbstractDagFileProcessorProcess] = {}
 

tests/test_configuration.py

@@ -599,3 +599,22 @@ def test_run_command(self):
 
     def test_confirm_unittest_mod(self):
         self.assertTrue(conf.get('core', 'unit_test_mode'))
+
+    @conf_vars({("core", "store_serialized_dags"): "True"})
+    def test_store_dag_code_default_config(self):
+        store_serialized_dags = conf.getboolean('core', 'store_serialized_dags', fallback=False)
+        store_dag_code = conf.getboolean("core", "store_dag_code", fallback=store_serialized_dags)
+        self.assertFalse(conf.has_option("core", "store_dag_code"))
+        self.assertTrue(store_serialized_dags)
+        self.assertTrue(store_dag_code)
+
+    @conf_vars({
+        ("core", "store_serialized_dags"): "True",
+        ("core", "store_dag_code"): "False"
+    })
+    def test_store_dag_code_config_when_set(self):
+        store_serialized_dags = conf.getboolean('core', 'store_serialized_dags', fallback=False)
+        store_dag_code = conf.getboolean("core", "store_dag_code", fallback=store_serialized_dags)
+        self.assertTrue(conf.has_option("core", "store_dag_code"))
+        self.assertTrue(store_serialized_dags)
+        self.assertFalse(store_dag_code)