Devices and Controllers

Tip

from leads import *

Device is the base class of every device, from sensors to motors. Controller is a special type of device that can contain child devices. By introducing controllers, we have a device tree. The tree always starts from a controller node known as the main controller.

Register a Controller

from leads import controller, MAIN_CONTROLLER
from leads_emulation import RandomController


@controller(MAIN_CONTROLLER)
class MainController(RandomController):
    pass

The example above registers RandomController as the main controller. MAIN_CONTROLLER is the tag of the controller. In the device tree, every device have a tag. You can use these predefined tags or custom strings.

Tip

All tags should be composed of lowercase letters and underscores only. It is not fatal, but it will make your project more disciplined.

Pass Arguments to the Controller

To pass arguments to the device constructor, just include them in the decorator.

from leads import controller, MAIN_CONTROLLER
from leads_emulation import RandomController


@controller(MAIN_CONTROLLER, args=(10, 100), kwargs={"skid_possibility": 0.5})
class MainController(RandomController()):
    pass

Register a Device

As the top node of the device tree is always a controller, all devices must have a parent.

from leads import device, controller, MAIN_CONTROLLER, ODOMETER, Odometer
from leads_emulation import RandomController


@controller(MAIN_CONTROLLER)
class MainController(RandomController()):
    pass


@device(ODOMETER, MAIN_CONTROLLER)
class ChildDevice(Odometer):
    pass

Register a Child Controller

Controllers can be child devices of other controllers as well.

from leads import controller, MAIN_CONTROLLER
from leads_emulation import RandomController, SinController


@controller(MAIN_CONTROLLER, args=(10, 100), kwargs={"skid_possibility": 0.5})
class MainController(RandomController()):
    pass


@controller("secondary_controller", MAIN_CONTROLLER)
class SecondaryController(SinController):
    pass