Update DryDock Operator

There is a need to pass workflow-related information in the form
of JSON string to Airflow via the ACTION API call from Shipyard.
In this way, we will be able to keep track/correlate actions
performed via Shipyard as well as to pass in the parameters that
we want Airflow to consume for its workflow.

A sample JSON string that we will pass in via Shipyard using the
Action API call will be similar to the following:

{
  "action": {
    "id": "1234567890",
    "name": "node_filter",
    "parameters": {
      "servername": "node2,node3"
    }
  }
}

This patch set is meant to update the DryDock Operator and its
related dags in order to support this implementation

The node_filter information will be passed in via the Shipyard
API call instead

Change-Id: I324959d5f42c98c5fcb1ac44c9677f818bfebbc1

shipyard_airflow/dags/drydock_operator_child.py

@@ -18,7 +18,6 @@ import configparser
 from airflow import DAG
 from airflow.operators import DryDockOperator
 
-
 def sub_dag(parent_dag_name, child_dag_name, args, schedule_interval):
     dag = DAG(
         '%s.%s' % (parent_dag_name, child_dag_name),
@@ -41,11 +40,6 @@ def sub_dag(parent_dag_name, child_dag_name, args, schedule_interval):
     drydock_conf = config.get('drydock', 'site_yaml')
     promenade_conf = config.get('drydock', 'prom_yaml')
 
-    # Convert to Dictionary
-    k8_masters_sting = config.get('drydock', 'k8_masters')
-    k8_masters_list = k8_masters_sting.split(',')
-    k8_masters = {'node_names': k8_masters_list}
-
     # Create Drydock Client
     t1 = DryDockOperator(
         task_id='create_drydock_client',
@@ -92,14 +86,12 @@ def sub_dag(parent_dag_name, child_dag_name, args, schedule_interval):
     t7 = DryDockOperator(
         task_id='drydock_prepare_node',
         action='prepare_node',
-        node_filter=k8_masters,
         dag=dag)
 
     # Deploy Node
     t8 = DryDockOperator(
         task_id='drydock_deploy_node',
         action='deploy_node',
-        node_filter=k8_masters,
         dag=dag)
 
     # Define dependencies

shipyard_airflow/dags/drydock_operator_parent.py

@@ -17,6 +17,7 @@
 import airflow
 from airflow import DAG
 from datetime import timedelta
+from airflow.operators.python_operator import PythonOperator
 from airflow.operators.subdag_operator import SubDagOperator
 from drydock_operator_child import sub_dag
 
@@ -40,9 +41,24 @@ main_dag = DAG(
     max_active_runs=1
 )
 
+# Define push function to store the content of 'action' that is
+# defined via 'dag_run' in XCOM so that it can be used by the
+# DryDock Operators
+def push(**kwargs):
+    # Pushes action XCom
+    kwargs['ti'].xcom_push(key='action',
+                           value=kwargs['dag_run'].conf['action'])
+
+
+action_xcom = PythonOperator(
+    task_id='action_xcom', dag=main_dag, python_callable=push)
+
 subdag = SubDagOperator(
     subdag=sub_dag(parent_dag_name, child_dag_name, args,
                    main_dag.schedule_interval),
     task_id=child_dag_name,
     default_args=args,
     dag=main_dag)
+
+# Set dependencies
+subdag.set_upstream(action_xcom)