Writing workflows
=================

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    A workflow in AiiDA is a process that can call other workflows and calculations to encode the logic of a typical scientific workflow.
    Currently, there are two ways of implementing a workflow process: work *functions* and work *chains*.
    In this section you will learn how to write both, as well as deal with more advanced topics such as debugging, input validation and error handling.

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    .. link-button:: workfunction
        :type: ref
        :text: Work functions
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    ^^^^^^^^^^^^

    A short module on how to write the basic type of workflows in AiiDA: work functions.
    The module also revises the usage of calculation functions to add simple Python functions to the provenance.

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        * - |time| 30 min
          - |aiida| :aiida-green:`Basic`

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    .. link-button:: workchain
        :type: ref
        :text: Work chains
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    ^^^^^^^^^^^^

    A step-by-step introduction to the basics of writing work chains in AiiDA.
    After completing this module, you will be ready to start writing your own scientific workflows!

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        * - |time| 60 min
          - |aiida| :aiida-green:`Basic`

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    .. link-button:: debugging
        :type: ref
        :text: Debugging work chains
        :classes: btn-light text-left stretched-link font-weight-bold
    ^^^^^^^^^^^^

    When writing your own work chain, things are bound to go wrong!
    Here we list some common issues with AiiDA work chains, what to expect, and how to debug them.

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        * - |time| 20 min
          - |aiida| :aiida-blue:`Intermediate`

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    .. link-button:: realworld
        :type: ref
        :text: A Real-world example - Equation of state
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    ^^^^^^^^^^^^

    A fully explained real-world work chain implemented in AiiDA, that can be used an example to start writing your own work chain.

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        * -
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        * - |time| 30 min
          - |aiida| :aiida-blue:`Intermediate`


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    .. link-button:: https://aiida.readthedocs.io/projects/aiida-core/en/latest/howto/write_workflows.html#extending-workflows
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        :text: Extending work chains
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    ^^^^^^^^^^^^

    Work chains are designed to be modular and reusable.
    This how-to *from the AiiDA documentation* explains how to efficiently extend our work chains.

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        * - |time| 20 min
          - |aiida| :aiida-blue:`Intermediate`

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    .. link-button:: errors
        :type: ref
        :text: Dealing with errors
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    ^^^^^^^^^^^^

    This module explains how to deal with errors in AiiDA workflows, and how to automatically recover from issues that occur for your calculations.

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        * - |time| 60 min
          - |aiida| :aiida-orange:`Advanced`


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    .. link-button:: https://filedn.com/lsOzB8TTUIDz2WkFj8o6qhp/memes/mossfire.gif
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        :text: Input validation
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    ^^^^^^^^^^^^

    **Under construction** 🔨

    Here we explain how to write a *validator* that can check inputs before running a calculation or workflow.

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        * - |time| 20 min
          - |aiida| :aiida-blue:`Intermediate`

.. toctree::
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    workfunction
    workchain
    debugging
    realworld
    validation
    errors