Deprecate some functions in the experimental API (#19931)

This PR seeks to deprecate some functions in the experimental API.
Some of the deprecated functions are only used in the experimental REST API,
others that are valid are being moved out of the experimental package.

(cherry picked from commit 6239ae9)

airflow/api/client/local_client.py

@@ -18,8 +18,10 @@
 """Local client API"""
 
 from airflow.api.client import api_client
-from airflow.api.common.experimental import delete_dag, pool, trigger_dag
+from airflow.api.common import delete_dag, trigger_dag
 from airflow.api.common.experimental.get_lineage import get_lineage as get_lineage_api
+from airflow.exceptions import AirflowBadRequest, PoolNotFound
+from airflow.models.pool import Pool
 
 
 class Client(api_client.Client):
@@ -36,19 +38,30 @@ def delete_dag(self, dag_id):
         return f"Removed {count} record(s)"
 
     def get_pool(self, name):
-        the_pool = pool.get_pool(name=name)
-        return the_pool.pool, the_pool.slots, the_pool.description
+        pool = Pool.get_pool(pool_name=name)
+        if not pool:
+            raise PoolNotFound(f"Pool {name} not found")
+        return pool.pool, pool.slots, pool.description
 
     def get_pools(self):
-        return [(p.pool, p.slots, p.description) for p in pool.get_pools()]
+        return [(p.pool, p.slots, p.description) for p in Pool.get_pools()]
 
     def create_pool(self, name, slots, description):
-        the_pool = pool.create_pool(name=name, slots=slots, description=description)
-        return the_pool.pool, the_pool.slots, the_pool.description
+        if not (name and name.strip()):
+            raise AirflowBadRequest("Pool name shouldn't be empty")
+        pool_name_length = Pool.pool.property.columns[0].type.length
+        if len(name) > pool_name_length:
+            raise AirflowBadRequest(f"pool name cannot be more than {pool_name_length} characters")
+        try:
+            slots = int(slots)
+        except ValueError:
+            raise AirflowBadRequest(f"Bad value for `slots`: {slots}")
+        pool = Pool.create_or_update_pool(name=name, slots=slots, description=description)
+        return pool.pool, pool.slots, pool.description
 
     def delete_pool(self, name):
-        the_pool = pool.delete_pool(name=name)
-        return the_pool.pool, the_pool.slots, the_pool.description
+        pool = Pool.delete_pool(name=name)
+        return pool.pool, pool.slots, pool.description
 
     def get_lineage(self, dag_id, execution_date):
         lineage = get_lineage_api(dag_id=dag_id, execution_date=execution_date)

airflow/api/common/delete_dag.py

@@ -0,0 +1,83 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+"""Delete DAGs APIs."""
+import logging
+
+from sqlalchemy import or_
+
+from airflow import models
+from airflow.exceptions import AirflowException, DagNotFound
+from airflow.models import DagModel, TaskFail
+from airflow.models.serialized_dag import SerializedDagModel
+from airflow.utils.db import get_sqla_model_classes
+from airflow.utils.session import provide_session
+from airflow.utils.state import State
+
+log = logging.getLogger(__name__)
+
+
+@provide_session
+def delete_dag(dag_id: str, keep_records_in_log: bool = True, session=None) -> int:
+    """
+    :param dag_id: the dag_id of the DAG to delete
+    :param keep_records_in_log: whether keep records of the given dag_id
+        in the Log table in the backend database (for reasons like auditing).
+        The default value is True.
+    :param session: session used
+    :return count of deleted dags
+    """
+    log.info("Deleting DAG: %s", dag_id)
+    running_tis = (
+        session.query(models.TaskInstance.state)
+        .filter(models.TaskInstance.dag_id == dag_id)
+        .filter(models.TaskInstance.state == State.RUNNING)
+        .first()
+    )
+    if running_tis:
+        raise AirflowException("TaskInstances still running")
+    dag = session.query(DagModel).filter(DagModel.dag_id == dag_id).first()
+    if dag is None:
+        raise DagNotFound(f"Dag id {dag_id} not found")
+
+    # Scheduler removes DAGs without files from serialized_dag table every dag_dir_list_interval.
+    # There may be a lag, so explicitly removes serialized DAG here.
+    if SerializedDagModel.has_dag(dag_id=dag_id, session=session):
+        SerializedDagModel.remove_dag(dag_id=dag_id, session=session)
+
+    count = 0
+
+    for model in get_sqla_model_classes():
+        if hasattr(model, "dag_id"):
+            if keep_records_in_log and model.__name__ == 'Log':
+                continue
+            cond = or_(model.dag_id == dag_id, model.dag_id.like(dag_id + ".%"))
+            count += session.query(model).filter(cond).delete(synchronize_session='fetch')
+    if dag.is_subdag:
+        parent_dag_id, task_id = dag_id.rsplit(".", 1)
+        for model in TaskFail, models.TaskInstance:
+            count += (
+                session.query(model).filter(model.dag_id == parent_dag_id, model.task_id == task_id).delete()
+            )
+
+    # Delete entries in Import Errors table for a deleted DAG
+    # This handles the case when the dag_id is changed in the file
+    session.query(models.ImportError).filter(models.ImportError.filename == dag.fileloc).delete(
+        synchronize_session='fetch'
+    )
+
+    return count

airflow/api/common/experimental/delete_dag.py

@@ -15,68 +15,12 @@
 # KIND, either express or implied.  See the License for the
 # specific language governing permissions and limitations
 # under the License.
-"""Delete DAGs APIs."""
-import logging
+import warnings
 
-from sqlalchemy import or_
+from airflow.api.common.delete_dag import *  # noqa
 
-from airflow import models
-from airflow.exceptions import AirflowException, DagNotFound
-from airflow.models import DagModel, TaskFail
-from airflow.models.serialized_dag import SerializedDagModel
-from airflow.utils.session import provide_session
-from airflow.utils.state import State
-
-log = logging.getLogger(__name__)
-
-
-@provide_session
-def delete_dag(dag_id: str, keep_records_in_log: bool = True, session=None) -> int:
-    """
-    :param dag_id: the dag_id of the DAG to delete
-    :param keep_records_in_log: whether keep records of the given dag_id
-        in the Log table in the backend database (for reasons like auditing).
-        The default value is True.
-    :param session: session used
-    :return count of deleted dags
-    """
-    log.info("Deleting DAG: %s", dag_id)
-    running_tis = (
-        session.query(models.TaskInstance.state)
-        .filter(models.TaskInstance.dag_id == dag_id)
-        .filter(models.TaskInstance.state == State.RUNNING)
-        .first()
-    )
-    if running_tis:
-        raise AirflowException("TaskInstances still running")
-    dag = session.query(DagModel).filter(DagModel.dag_id == dag_id).first()
-    if dag is None:
-        raise DagNotFound(f"Dag id {dag_id} not found")
-
-    # Scheduler removes DAGs without files from serialized_dag table every dag_dir_list_interval.
-    # There may be a lag, so explicitly removes serialized DAG here.
-    if SerializedDagModel.has_dag(dag_id=dag_id, session=session):
-        SerializedDagModel.remove_dag(dag_id=dag_id, session=session)
-
-    count = 0
-
-    for model in models.base.Base._decl_class_registry.values():
-        if hasattr(model, "dag_id"):
-            if keep_records_in_log and model.__name__ == 'Log':
-                continue
-            cond = or_(model.dag_id == dag_id, model.dag_id.like(dag_id + ".%"))
-            count += session.query(model).filter(cond).delete(synchronize_session='fetch')
-    if dag.is_subdag:
-        parent_dag_id, task_id = dag_id.rsplit(".", 1)
-        for model in TaskFail, models.TaskInstance:
-            count += (
-                session.query(model).filter(model.dag_id == parent_dag_id, model.task_id == task_id).delete()
-            )
-
-    # Delete entries in Import Errors table for a deleted DAG
-    # This handles the case when the dag_id is changed in the file
-    session.query(models.ImportError).filter(models.ImportError.filename == dag.fileloc).delete(
-        synchronize_session='fetch'
-    )
-
-    return count
+warnings.warn(
+    "This module is deprecated. Please use `airflow.api.common.delete_dag` instead.",
+    DeprecationWarning,
+    stacklevel=2,
+)

airflow/api/common/experimental/get_code.py

@@ -16,11 +16,14 @@
 # specific language governing permissions and limitations
 # under the License.
 """Get code APIs."""
+from deprecated import deprecated
+
 from airflow.api.common.experimental import check_and_get_dag
 from airflow.exceptions import AirflowException, DagCodeNotFound
 from airflow.models.dagcode import DagCode
 
 
+@deprecated(reason="Use DagCode().get_code_by_fileloc() instead", version="2.2.3")
 def get_code(dag_id: str) -> str:
     """Return python code of a given dag_id.
 

airflow/api/common/experimental/get_dag_run_state.py

@@ -19,9 +19,12 @@
 from datetime import datetime
 from typing import Dict
 
+from deprecated import deprecated
+
 from airflow.api.common.experimental import check_and_get_dag, check_and_get_dagrun
 
 
+@deprecated(reason="Use DagRun().get_state() instead", version="2.2.3")
 def get_dag_run_state(dag_id: str, execution_date: datetime) -> Dict[str, str]:
     """Return the Dag Run state identified by the given dag_id and execution_date.
 

airflow/api/common/experimental/get_task.py

@@ -16,10 +16,13 @@
 # specific language governing permissions and limitations
 # under the License.
 """Task APIs.."""
+from deprecated import deprecated
+
 from airflow.api.common.experimental import check_and_get_dag
 from airflow.models import TaskInstance
 
 
+@deprecated(reason="Use DAG().get_task", version="2.2.3")
 def get_task(dag_id: str, task_id: str) -> TaskInstance:
     """Return the task object identified by the given dag_id and task_id."""
     dag = check_and_get_dag(dag_id, task_id)

airflow/api/common/experimental/get_task_instance.py

@@ -18,11 +18,14 @@
 """Task Instance APIs."""
 from datetime import datetime
 
+from deprecated import deprecated
+
 from airflow.api.common.experimental import check_and_get_dag, check_and_get_dagrun
 from airflow.exceptions import TaskInstanceNotFound
 from airflow.models import TaskInstance
 
 
+@deprecated(version="2.2.3", reason="Use DagRun.get_task_instance instead")
 def get_task_instance(dag_id: str, task_id: str, execution_date: datetime) -> TaskInstance:
     """Return the task instance identified by the given dag_id, task_id and execution_date."""
     dag = check_and_get_dag(dag_id, task_id)

airflow/api/common/experimental/pool.py

@@ -16,11 +16,14 @@
 # specific language governing permissions and limitations
 # under the License.
 """Pool APIs."""
+from deprecated import deprecated
+
 from airflow.exceptions import AirflowBadRequest, PoolNotFound
 from airflow.models import Pool
 from airflow.utils.session import provide_session
 
 
+@deprecated(reason="Use Pool.get_pool() instead", version="2.2.3")
 @provide_session
 def get_pool(name, session=None):
     """Get pool by a given name."""
@@ -34,12 +37,14 @@ def get_pool(name, session=None):
     return pool
 
 
+@deprecated(reason="Use Pool.get_pools() instead", version="2.2.3")
 @provide_session
 def get_pools(session=None):
     """Get all pools."""
     return session.query(Pool).all()
 
 
+@deprecated(reason="Use Pool.create_pool() instead", version="2.2.3")
 @provide_session
 def create_pool(name, slots, description, session=None):
     """Create a pool with a given parameters."""
@@ -70,6 +75,7 @@ def create_pool(name, slots, description, session=None):
     return pool
 
 
+@deprecated(reason="Use Pool.delete_pool() instead", version="2.2.3")
 @provide_session
 def delete_pool(name, session=None):
     """Delete pool by a given name."""