hwm.hardware.devices.manager.DeviceManager Class Reference

Manages access to configured hardware devices. More...

Public Member Functions
def	__init__
	Initializes the device manager and all configured devices. More...
def	get_device_driver
	Loads and returns the driver for the specified device. More...

Public Attributes
	config
	devices
	virtual_devices

Private Member Functions
def	_initialize_devices
	Initializes the drivers for each device. More...
def	_validate_devices
	Validates the provided device configuration. More...

Private Attributes
	_command_parser

Detailed Description

Manages access to configured hardware devices.

This class is responsible for providing access to the hardware device drivers currently configured at the ground station. Like the other "manager" classes, there will only be a single instance of this class created early on. When initialized, the device manager initializes the appropriate drivers for the hardware devices specified in the configuration.

Note

All device usage locking is done by the device driver. See the driver base class for more.

Constructor & Destructor Documentation

def hwm.hardware.devices.manager.DeviceManager.__init__	(		self,
			command_parser
	)

Initializes the device manager and all configured devices.

 This constructor initializes the device manager and creates the appropriate driver class instances for all
 configured hardware devices.

Parameters

command_parser

A reference to the active CommandParser instance.

Note

This class relies on configuration loaded into the configuration manager during the startup process. Therefore, if this class is initialized before the appropriate configuration files have been read, an exception will be generated.

Exceptions

This	constructor may pass exceptions raised during the device driver initialization process (see _initialize_devices).

Member Function Documentation

def hwm.hardware.devices.manager.DeviceManager._initialize_devices (   self)

private

Initializes the drivers for each device.

 This method stores references to device driver instances or classes as defined by the device configuration. If a
 device is a physical device, then its driver will be initialized and stored. However, if the device is a virtual
 device then a reference to its class will be stored instead (so it can be initialized on the fly later).

Note

Device drivers should be named so that the lower case version of the driver name (as specified in devices.yml) refers to the package and module in hwm.devices.drivers. Underscores are allowed to improve readability. For example, the driver "Test_Driver" refers to the "Test_Driver" class in the "test_driver" module in the "test_driver" package.

Exceptions

Throws	DevicesAlreadyInitialized if drivers have already been loaded into the device manager.
Throws	DeviceConfigInvalid in the event that device configuration specified in self.config is invalid (wrong format). This may be passed on from _validate_devices().
Throws	DriverNotFound in the event that a driver class can't be located.
Throws	DriverInitError in the event that a driver class can't be initialized (i.e. its constructor throws an exception).

def hwm.hardware.devices.manager.DeviceManager._validate_devices (   self,   device_configuration  )

private

Validates the provided device configuration.

 This method verifies that the provided device configuration conforms to the defined schema.

Note

This method doesn't validate any of the device settings. It is up to the device drivers to do this during initialization.

Exceptions

Throws

DeviceConfigInvalid in the event that the device configuration is invalid.

Parameters

device_configuration

An array containing the available device configuration.

def hwm.hardware.devices.manager.DeviceManager.get_device_driver	(		self,
			device_id
	)

Loads and returns the driver for the specified device.

 This method returns an instance of the device driver class for the specified device. If the requested device is a 
 physical device a reference to a previously initialized driver will be returned. If the requested device is a 
 virtual device a new instance will be constructed and returned.

Note

This method is typically called by pipelines during initialization when loading their devices. Virtual device driver instances are created on the fly because, unlike physical device drivers, they are typically tied to a specific pipeline with each pipeline having its own instance.

Exceptions

Throws

DeviceNotFound if the specified device can't be located.

Parameters

device_id

The ID of the device associated with the returned driver.

Returns

Returns a reference to the driver class for the specified device.

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The documentation for this class was generated from the following file:

• hwm/hardware/devices/manager.py