Source code for airflow.operators.branch_operator

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"""Branching operators"""

from typing import Union, Iterable, Dict

from airflow.models import BaseOperator, SkipMixin

[docs]class BaseBranchOperator(BaseOperator, SkipMixin): """ This is a base class for creating operators with branching functionality, similarly to BranchPythonOperator. Users should subclass this operator and implement the function `choose_branch(self, context)`. This should run whatever business logic is needed to determine the branch, and return either the task_id for a single task (as a str) or a list of task_ids. The operator will continue with the returned task_id(s), and all other tasks directly downstream of this operator will be skipped. """
[docs] def choose_branch(self, context): # type: (Dict) -> Union[str, Iterable[str]] """ Subclasses should implement this, running whatever logic is necessary to choose a branch and returning a task_id or list of task_ids. :param context: Context dictionary as passed to execute() :type context: dict """ raise NotImplementedError
[docs] def execute(self, context): self.skip_all_except(context['ti'], self.choose_branch(context))