DOC: Add documentation on how to build the docs

docs/development/build_docs.rst

@@ -0,0 +1,97 @@
+RocketPy documentation
+======================
+
+RocketPy uses `Sphinx <https://www.sphinx-doc.org/>`_ to generate the
+documentation.
+Sphinx makes it easy to create documentation for Python projects and it is
+widely used for Python projects, such as
+`NumPy <https://numpy.org/doc/stable/>`_,
+`Pandas <https://pandas.pydata.org/docs/>`_ and
+`SciPy <https://docs.scipy.org/doc/scipy/>`_.
+
+
+The `ReadTheDocs <https://about.readthedocs.com/?ref=readthedocs.com>`_ is used
+to host the documentation. It is a free service that automatically builds
+documentation from your sphinx source files and hosts them for free.
+
+RocketPy official documentation is available at
+`https://docs.rocketpy.org <https://docs.rocketpy.org/en/latest/index.html>`_.
+
+
+How to build the documentation in your local machine
+----------------------------------------------------
+
+When you find yourself modifying the documentation files and trying to see the
+results, you can build the documentation in your local machine.
+This is important to check if the documentation is being generated correctly
+before pushing the changes to the repository.
+
+To build the documentation in your local machine, you need to install a set of
+requirements that are needed to run the sphinx generator.
+All these requirements are listed in the ``requirements.txt`` file inside the
+``docs`` folder.
+
+To install the requirements, navigate the terminal to the ``docs`` folder and
+run the following command:
+
+.. code-block:: bash
+
+    pip install -r requirements.txt
+
+After installing the requirements, you can build the documentation by running
+the following command in your terminal:
+
+.. code-block:: bash
+
+    make html
+
+The file named ``Makefile`` contains the commands to build the documentation.
+The ``make html`` command will generate the documentation in the ``docs/_build/html``
+folder.
+
+To see the documentation, open the ``docs/_build/html/index.html`` file in your
+browser.
+
+.. note:: Watch out for any warnings or errors that may appear in the terminal
+          when building the documentation. If you find any, fix them before
+          pushing the changes to the repository or at least warn the team about
+          them.
+
+Sometimes you may face problems when building the documentation after several
+times of building it.
+This may happen because sphinx does not clean the ``docs/_build`` folder before
+building the documentation again.
+To clean the ``docs/_build`` folder, run the following command in your terminal:
+
+.. code-block:: bash
+
+    make clean
+
+After cleaning the ``docs/_build`` folder, you can build the documentation again
+by running the ``make html`` command.
+
+If the error persists, it may be related to other files, such as the ``.rst``
+files or the ``conf.py`` file.
+
+.. danger:: Do not modify the Makefile or the ``make.bat`` files. These files are
+            automatically generated by sphinx and any changes will be lost.
+
+
+How to integrate the documentation with ReadTheDocs
+---------------------------------------------------
+
+The documentation is automatically built and hosted by `ReadTheDocs`.
+Every time a commit is pushed to the repository, `ReadTheDocs` will build the
+documentation and host it automatically. 
+This includes other branches besides the master branch.
+However, the documentation will only be available for the master branch, and you
+need to configure the `ReadTheDocs` project to build the documentation for other
+branches.
+
+The connection between the GitHub repository and the `ReadTheDocs` project is
+already configured and defined in the ``readthedocs.yml`` file, available at the
+root of the repository.
+
+.. note:: You need admin permissions to configure the `ReadTheDocs` project. Ask
+          the team for help if you don't have admin permissions.
+

docs/development/index.rst

@@ -8,5 +8,6 @@ Contributing to RocketPy
    Running RocketPy as a Developer <rocketpy_as_developer.rst>
    GitHub Workflow for RocketPy Hackathon 2022 <github_hackathon.rst>
    Style Guide <style_guide>
+   Building the Documentation <build_docs.rst>
 
 This section is still a work in progress. Here you will find information on how to contribute to our code base.