Extension packaging

To be dynamically discoverable, Opsdroid extensions developed and deployed as regular Python packages must define so-called entry points, one for each individual opsdroid extension.

The entry points are grouped by extension type (skill, connector or database). The groups are called opsdroid_skills, opsdroid_connectors and opsdroid_databases.

Defining entry points for opsdroid is as simple as adding a small dict entry to the setup.py file of the extension package. For example:

 entry_points = {
     'opsdroid_databases': [
         'zodb = opsdroid_zodb.database'
      ]
 },

(an excerpt from setup.py file of the opsdroid-zodb extension package)

In the above example, entry_points is just yet another named keyword argument to the setup() call found in setup.py. It defines a opsdroid ZODB database extension whose name is 'zodb'. It then declares that opsdroid should import the extension from the database module of a opsdroid_zodb package.

An extension package with the above entry point could be used from configuration.yaml simply thus:

databases:
  ## From a installed Python package
  - name: zodb

That's all! Opsdroid will see the zodb extension name, check it against all opsdroid_databases entry points it is aware of, import the extension and use it.

The above entry point example defines just one database extension. To add more database extensions, or also skill(s) or connector(s), simply add them to the same dict data structure, following the extension group naming convention given above.