.. currentmodule:: royalnet

Creating a new Pack
====================================

Prerequisites
------------------------------------

You'll need to have `Python 3.8 <https://www.pyth1on.org/downloads/release/python-382/>`_ and `poetry <https://github.com/python-poetry/poetry>`_
to develop Royalnet Packs.

Creating the repository
------------------------------------

To create a new pack, create a new repository based on the `Royalnet Pack template <https://github.com/Steffo99/royalnet-pack-template>`_
and clone it to your workspace.

After cloning the template, run ``poetry install`` to create a virtualenv and install the dependencies for the pack in it.

pyproject.toml
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The ``pyproject.toml`` file contains information about your Python project that will be read by ``poetry`` while building
the pack and publishing it to PyPI.

Choose a name for your Pack and set it in the ``tool.property.name`` field: ::

    [tool.poetry]
        # TODO: Insert here your Pack name!
        name = "pastapack"
        # ...

Follow the instructions in the other ``# TODO`` comments to finish editing the file.

examplepack
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The ``examplepack`` folder contains the source code of your pack, and should be renamed to the name you set in the ``pyproject.toml`` file.

It should contain six folders: ::

    examplepack
    ├── commands
    ├── events
    ├── stars
    ├── tables
    ├── types
    └── utils

The commands folder
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The commands folder should contain all commands that your Pack will add to the Royalnet instances it is installed in.

To learn how to create a new :class:`~commands.Command`, read the :doc:`command` page.

The events folder
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The events folder should contain all events (remote procedure calls) that your Pack will add to the Royalnet instances it is installed in.

To learn how to create a new :class:`~commands.Event`, read the :doc:`event` page.

The stars folder
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The stars folder should contain all stars (webserver routes) that your Pack will add to the Royalnet instances it is installed in.

To learn how to create a new :class:`~constellation.PageStar`, read the :doc:`star` page.

The tables folder
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The tables folder should contain all Alchemy tables (SQLAlchemy-compatible SQL tables) that your Pack will add to the Royalnet instances it is installed in.

To learn how to create a new table, read the :doc:`table` page.

The utils folder
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The utils folder should contain the utility functions and classes that your Pack uses.

Its contents are imported **before** the commands, events and stars but **after** the tables, so **you can't import them** in the files contained in the ``tables`` folder, or you will create a `circular import <https://stackabuse.com/python-circular-imports/>`_!

Files in this folder are **forbidden from importing modules** from the ``commands``, ``events`` and ``stars`` folders, as that will create a circular import too.

The types folder
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The types folder should contain the enums and custom types that are used in your tables.

Please note that the contents of this folder are imported **before** everything else in the pack.

Its contents **can be imported anywhere** in the Pack, including the ``tables`` folder, without creating a circular import.

However, its files are **forbidden from importing anything else** from the rest of the pack!

Adding new dependencies to the Pack
------------------------------------

As the Pack is actually a Python package, you can use ``poetry`` to add new dependencies!

Use ``poetry add packagename`` to add and install a new dependency from the PyPI.

Updating the dependencies
------------------------------------

You can update all your dependencies by using: ``poetry update``.

The README.md file
------------------------------------

The README.md file is the first thing that users of your pack will see!

It's recommended to describe accurately how to install and configure the pack, so other users will be able to use it too!

Publishing the pack
------------------------------------

To publish your Pack on the PyPI, run ``poetry publish --build``.

Poetry will build your Pack and upload it to the PyPI for you!