How to write your own plugin

To develop your own Rasahub plugin and provide it as a pypi package there are a few steps needed.

First, create a directory to store all your plugin files, for example: ‘example-plugin’. Then, create another directory in your newly created one with the name of your plugin with rasahub_ prefix. For example: rasahub_example.

In example-plugin you have to create following files:

• LICENSE.txt - containing the license information of your plugin
• MANIFEST.in - containing following string:

include LICENSE README.rst

• README.rst - with a basic documentation of your plugin
• setup.py - with setup information for python.

Content of setup.py

In setup.py you state the plugins name, dependency, version and so on. A basic example of setup.py looks like this:

from setuptools import setup, find_packages

install_requires = [
    'rasahub',
]

tests_requires = [
]

extras_requires = {
    'test': tests_requires
}

setup(name='rasahub-example',
      version='0.0.1',
      description='Example plugin for Rasahub',
      url='http://github.com/frommie/rasahub-example',
      author='Jon Doe',
      author_email='jon.doe@foobar.baz',
      license='MIT',
      classifiers=[
          'Development Status :: 3 - Alpha',
          'License :: OSI Approved :: MIT License',
          'Intended Audience :: Developers',
          'Programming Language :: Python :: 2.7',
          'Topic :: Software Development',
      ],
      keywords='rasahub example plugin',
      packages=find_packages(exclude=['docs', 'tests']),
      install_requires=install_requires,
      tests_require=tests_requires,
      extras_require=extras_requires,
)

The Plugin Itself

After we created all the python-related files we can start developing the plugin itself! In your rasahub_example directory create a file called __init__.py . There you define your Plugin class and the initialization method:

from rasahub import RasahubPlugin
from rasahub.message import RasahubMessage

import fancy_api

    class ExamplePlugin(RasahubPlugin):
        """
        ExamplePlugin is subclass of RasahubPlugin
        """
        def __init__(self, parameter = 'default-value'):
            """
            Initializes the example plugin
            """

            super(HumhubConnector, self).__init__()

            self.apiconnection = fancy_api.connect(parameter)


        def send(self, messagedata, main_queue):
            """
            Sends message to example plugin output like socket connection or
            database
            """
            self.apiconnection.save(messagedata)


        def receive(self):
            """
            Receives message from plugin input
            """
            return self.apiconnection.receive()


        def process_command(self, command, payload, out_message):
            """
            Command hook before sending, returns a Rasahub message object
            """
            reply = RasahubMessage(
                message = "Command unknown",
                message_id = payload['message_id'],
                target = payload['message_target'],
                source = payload['message_source']
            )
            return reply


            def end(self):
                """
                Closes connections
                """
                self.apiconnection.close()