.. _architecture:

============
Architecture
============

Microservices
=============

REST API


Plugins and Sensors
===================

Sensors must be groupped in plugins: the idea is that each plugin gives
access to one or (typically) more sensors. Plugins are intended to be used
by ``stevedore`` as extensions, i.e. ``stevedore.extension.Extension``,
such that the plugins are automatically found and loaded.

The plugin implementation is, of course, ``stevedore``-agnostic and they
are just expected to behave as ``limonada.plugin.PluginBase`` although for
now nothing is enforced, from the typing point of view, and all the
mechanism of loading plugins is purely based on duck typing and on the
``stevedore`` machinery of defining extensions.

A plugin must have an entry point in the ``pyptoject.toml`` file, or
similar, and it should belong to the ``limonada.plugins`` namespace.

One example of plugin is ``psutil``. It provides 22 sensors, such as
``CPUTimesSensor``, ``BatterySensor`` etc.

.. note::

   The plan is to have builtin plugins, optional plugins and third party
   plugins, each offering different sensors. Some sensor names could be
   masked by others! A mechanism to select which one to use in such
   situations must be still devised.