# -*- coding: utf-8 -*-
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import datetime
import six
from airflow.models import BaseOperator
from airflow.utils import timezone
from airflow.utils.decorators import apply_defaults
from airflow.api.common.experimental.trigger_dag import trigger_dag
import json
class DagRunOrder(object):
def __init__(self, run_id=None, payload=None):
self.run_id = run_id
self.payload = payload
[docs]class TriggerDagRunOperator(BaseOperator):
"""
Triggers a DAG run for a specified ``dag_id``
:param trigger_dag_id: the dag_id to trigger (templated)
:type trigger_dag_id: str
:param python_callable: a reference to a python function that will be
called while passing it the ``context`` object and a placeholder
object ``obj`` for your callable to fill and return if you want
a DagRun created. This ``obj`` object contains a ``run_id`` and
``payload`` attribute that you can modify in your function.
The ``run_id`` should be a unique identifier for that DAG run, and
the payload has to be a picklable object that will be made available
to your tasks while executing that DAG run. Your function header
should look like ``def foo(context, dag_run_obj):``
:type python_callable: python callable
:param execution_date: Execution date for the dag (templated)
:type execution_date: str or datetime.datetime
"""
template_fields = ('trigger_dag_id', 'execution_date')
template_ext = tuple()
ui_color = '#ffefeb'
@apply_defaults
def __init__(
self,
trigger_dag_id,
python_callable=None,
execution_date=None,
*args, **kwargs):
super(TriggerDagRunOperator, self).__init__(*args, **kwargs)
self.python_callable = python_callable
self.trigger_dag_id = trigger_dag_id
if isinstance(execution_date, datetime.datetime):
self.execution_date = execution_date.isoformat()
elif isinstance(execution_date, six.string_types):
self.execution_date = execution_date
elif execution_date is None:
self.execution_date = execution_date
else:
raise TypeError(
'Expected str or datetime.datetime type '
'for execution_date. Got {}'.format(
type(execution_date)))
def execute(self, context):
if self.execution_date is not None:
run_id = 'trig__{}'.format(self.execution_date)
self.execution_date = timezone.parse(self.execution_date)
else:
run_id = 'trig__' + timezone.utcnow().isoformat()
dro = DagRunOrder(run_id=run_id)
if self.python_callable is not None:
dro = self.python_callable(context, dro)
if dro:
trigger_dag(dag_id=self.trigger_dag_id,
run_id=dro.run_id,
conf=json.dumps(dro.payload),
execution_date=self.execution_date,
replace_microseconds=False)
else:
self.log.info("Criteria not met, moving on")