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:mod:`airflow.operators.python_operator`
========================================
.. py:module:: airflow.operators.python_operator
Module Contents
---------------
.. py:class:: PythonOperator(python_callable, op_args=None, op_kwargs=None, provide_context=False, templates_dict=None, templates_exts=None, *args, **kwargs)
Bases: :class:`airflow.models.BaseOperator`
Executes a Python callable
.. seealso::
For more information on how to use this operator, take a look at the guide:
:ref:`howto/operator:PythonOperator`
:param python_callable: A reference to an object that is callable
:type python_callable: python callable
:param op_kwargs: a dictionary of keyword arguments that will get unpacked
in your function
:type op_kwargs: dict (templated)
:param op_args: a list of positional arguments that will get unpacked when
calling your callable
:type op_args: list (templated)
:param provide_context: if set to true, Airflow will pass a set of
keyword arguments that can be used in your function. This set of
kwargs correspond exactly to what you can use in your jinja
templates. For this to work, you need to define `**kwargs` in your
function header.
:type provide_context: bool
:param templates_dict: a dictionary where the values are templates that
will get templated by the Airflow engine sometime between
``__init__`` and ``execute`` takes place and are made available
in your callable's context after the template has been applied. (templated)
:type templates_dict: dict[str]
:param templates_exts: a list of file extensions to resolve while
processing templated fields, for examples ``['.sql', '.hql']``
:type templates_exts: list[str]
.. attribute:: template_fields
:annotation: = ['templates_dict', 'op_args', 'op_kwargs']
.. attribute:: ui_color
:annotation: = #ffefeb
.. attribute:: shallow_copy_attrs
:annotation: = ['python_callable', 'op_kwargs']
.. method:: execute(self, context)
.. method:: execute_callable(self)
.. py:class:: BranchPythonOperator
Bases: :class:`airflow.operators.python_operator.PythonOperator`, :class:`airflow.models.SkipMixin`
Allows a workflow to "branch" or follow a path following the execution
of this task.
It derives the PythonOperator and expects a Python function that returns
a single task_id or list of task_ids to follow. The task_id(s) returned
should point to a task directly downstream from {self}. All other "branches"
or directly downstream tasks are marked with a state of ``skipped`` so that
these paths can't move forward. The ``skipped`` states are propagated
downstream to allow for the DAG state to fill up and the DAG run's state
to be inferred.
Note that using tasks with ``depends_on_past=True`` downstream from
``BranchPythonOperator`` is logically unsound as ``skipped`` status
will invariably lead to block tasks that depend on their past successes.
``skipped`` states propagates where all directly upstream tasks are
``skipped``.
.. method:: execute(self, context)
.. py:class:: ShortCircuitOperator
Bases: :class:`airflow.operators.python_operator.PythonOperator`, :class:`airflow.models.SkipMixin`
Allows a workflow to continue only if a condition is met. Otherwise, the
workflow "short-circuits" and downstream tasks are skipped.
The ShortCircuitOperator is derived from the PythonOperator. It evaluates a
condition and short-circuits the workflow if the condition is False. Any
downstream tasks are marked with a state of "skipped". If the condition is
True, downstream tasks proceed as normal.
The condition is determined by the result of `python_callable`.
.. method:: execute(self, context)
.. py:class:: PythonVirtualenvOperator(python_callable, requirements=None, python_version=None, use_dill=False, system_site_packages=True, op_args=None, op_kwargs=None, provide_context=False, string_args=None, templates_dict=None, templates_exts=None, *args, **kwargs)
Bases: :class:`airflow.operators.python_operator.PythonOperator`
Allows one to run a function in a virtualenv that is created and destroyed
automatically (with certain caveats).
The function must be defined using def, and not be
part of a class. All imports must happen inside the function
and no variables outside of the scope may be referenced. A global scope
variable named virtualenv_string_args will be available (populated by
string_args). In addition, one can pass stuff through op_args and op_kwargs, and one
can use a return value.
Note that if your virtualenv runs in a different Python major version than Airflow,
you cannot use return values, op_args, or op_kwargs. You can use string_args though.
:param python_callable: A python function with no references to outside variables,
defined with def, which will be run in a virtualenv
:type python_callable: function
:param requirements: A list of requirements as specified in a pip install command
:type requirements: list[str]
:param python_version: The Python version to run the virtualenv with. Note that
both 2 and 2.7 are acceptable forms.
:type python_version: str
:param use_dill: Whether to use dill to serialize
the args and result (pickle is default). This allow more complex types
but requires you to include dill in your requirements.
:type use_dill: bool
:param system_site_packages: Whether to include
system_site_packages in your virtualenv.
See virtualenv documentation for more information.
:type system_site_packages: bool
:param op_args: A list of positional arguments to pass to python_callable.
:type op_kwargs: list
:param op_kwargs: A dict of keyword arguments to pass to python_callable.
:type op_kwargs: dict
:param provide_context: if set to true, Airflow will pass a set of
keyword arguments that can be used in your function. This set of
kwargs correspond exactly to what you can use in your jinja
templates. For this to work, you need to define `**kwargs` in your
function header.
:type provide_context: bool
:param string_args: Strings that are present in the global var virtualenv_string_args,
available to python_callable at runtime as a list[str]. Note that args are split
by newline.
:type string_args: list[str]
:param templates_dict: a dictionary where the values are templates that
will get templated by the Airflow engine sometime between
``__init__`` and ``execute`` takes place and are made available
in your callable's context after the template has been applied
:type templates_dict: dict of str
:param templates_exts: a list of file extensions to resolve while
processing templated fields, for examples ``['.sql', '.hql']``
:type templates_exts: list[str]
.. method:: execute_callable(self)
.. method:: _pass_op_args(self)
.. method:: _execute_in_subprocess(self, cmd)
.. method:: _write_string_args(self, filename)
.. method:: _write_args(self, input_filename)
.. method:: _read_result(self, output_filename)
.. method:: _write_script(self, script_filename)
.. method:: _generate_virtualenv_cmd(self, tmp_dir)
.. method:: _generate_pip_install_cmd(self, tmp_dir)
.. staticmethod:: _generate_python_cmd(tmp_dir, script_filename, input_filename, output_filename, string_args_filename)
.. method:: _generate_python_code(self)