Auto save value
===============

.. objectives:: Objectives

   A default value is a value that can be recalculated at different times. It can be useful to consider the default value as a modified value.

.. prerequisites:: Prerequisites

    - We assume that Rougail's library is :ref:`installed <installation>` on your computer.

    - It is possible to retrieve the current state of the various Rougail files manipulated in this tutorial step
      by checking out the corresponding tag of the `rougail-tutorials` git repository.
      Each tag corresponds to a stage of progress in the tutorial.
      Of course, you can also decide to copy/paste or download the tutorial files contents while following the tutorial steps.

    If you want to follow this tutorial with the help of the corresponding :tutorial:`rougail-tutorials git repository <src/branch/1.1>`, 
    this workshop page corresponds to the tag :tutorial:`v1.1_210 <src/tag/v1.1_210/README.md>`

    ::
   
       git clone https://forge.cloud.silique.fr/stove/rougail-tutorials.git
       git switch --detach v1.1_210

The :ref:`configuration` is loaded into :term:`Tiramisu`. In this case, the default values are cached upon the first access to the variable. However, sometimes this value will be recalculated.
If the default value is random, this can cause problems. Indeed, the value can change over time.

The `auto_save` property allows you to say that the calculated value will be considered as modified (therefore not recalculated) on the first access to this variable.

Remember, we just performed a random calculation for the variable `color`:

.. extinclude:: https://forge.cloud.silique.fr/stove/rougail-tutorials/raw/tag/v1.1_201/foxyproxy/00-foxyproxy.yml
   :language: yaml
   :caption: Calculate the default variable `color`.

We just need to set the `auto_save` property to true on this variable:

.. extinclude:: https://forge.cloud.silique.fr/stove/rougail-tutorials/raw/tag/v1.1_210/foxyproxy/00-foxyproxy.yml
   :language: yaml
   :caption: Auto_save for the variable `color`.

Test this variable with this Rougail CLI: 

.. raw:: html
   :class: terminal
   :url: https://forge.cloud.silique.fr/stove/rougail-tutorials/raw/commit/v1.1_210/config/02/cmd_ro.txt

We have this output:

.. raw:: html
   :class: output
   :url: https://forge.cloud.silique.fr/stove/rougail-tutorials/raw/tag/v1.1_210/config/02/output_ro.html

As you can see, the value is the color of the modified variables.

.. note::

   We do not save this value. It is therefore stored in memory. When the Rougail CLI closes, this value is forgotten. It will be recalculated if you run the command again.

.. keypoints:: Key points

   We can auto save a variable.