.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "starterkit/Ex06_basf2_reconstruction.py"
.. LINE NUMBERS ARE GIVEN BELOW.

.. only:: html

    .. note::
        :class: sphx-glr-download-link-note

        :ref:`Go to the end <sphx_glr_download_starterkit_Ex06_basf2_reconstruction.py>`
        to download the full example code.

.. rst-class:: sphx-glr-example-title

.. _sphx_glr_starterkit_Ex06_basf2_reconstruction.py:


.. _exercise06_label:

The ``requires`` decorator
==========================

.. hint::
    This example demonstrates how to create a simple ``b2luigi`` task that
    executes the reconstruction of previously simulated events. The key point of
    this example is the ``requires`` decorator.

We start with the usual imports. Note that we import the task ``SimulationTask``
class defined in the previous example :ref:`exercise05_label`: it's generally recommended
to keep your code as much modular as possible.

.. GENERATED FROM PYTHON SOURCE LINES 16-26

.. code-block:: Python


    import basf2 as b2
    import reconstruction as re
    import mdst

    import b2luigi
    from b2luigi.basf2_helper import Basf2PathTask
    from Ex05_basf2_simulation import SimulationTask



.. GENERATED FROM PYTHON SOURCE LINES 27-32

Here, I make use of the ``requires`` decorator to require the ``SimulationTask``.
This functionality is very useful when the dependencies of tasks are very
easily defined. The task with the ``requires`` decorator will automatically
create the ``requires`` method that returns the required task. Additionally,
the task also inherits all the parameters of the required task.

.. GENERATED FROM PYTHON SOURCE LINES 35-59

.. code-block:: Python

    @b2luigi.requires(SimulationTask)
    class ReconstructionTask(Basf2PathTask):
        result_dir = "results/Reconstruction"
        batch_system = "local"

        def output(self):
            yield self.add_to_output("reconstruction.root")

        def create_path(self):
            main = b2.Path()

            # Read the simulated events that were created in the simulation task.
            main.add_module("RootInput", inputFileNames=self.get_input_file_names("simulation.root"))

            # Run reconstruction
            main.add_module("Gearbox")
            main.add_module("Geometry")
            re.add_reconstruction(main)

            # Add MDST output.
            mdst.add_mdst_output(path=main, filename=self.get_output_file_name("reconstruction.root"))
            return main



.. GENERATED FROM PYTHON SOURCE LINES 60-63

As already pointed out in the second example, here we only need to
call the ``ReconstructionTask``: the scheduler will resolves all the
required dependencies.

.. GENERATED FROM PYTHON SOURCE LINES 63-65

.. code-block:: Python

    if __name__ == "__main__":
        b2luigi.process(ReconstructionTask(n_events=10))


.. _sphx_glr_download_starterkit_Ex06_basf2_reconstruction.py:

.. only:: html

  .. container:: sphx-glr-footer sphx-glr-footer-example

    .. container:: sphx-glr-download sphx-glr-download-python

      :download:`Download Python source code: Ex06_basf2_reconstruction.py <Ex06_basf2_reconstruction.py>`

    .. container:: sphx-glr-download sphx-glr-download-zip

      :download:`Download zipped: Ex06_basf2_reconstruction.zip <Ex06_basf2_reconstruction.zip>`


.. only:: html

 .. rst-class:: sphx-glr-signature

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