Subarray¶

SKASubarray

A SubArray handling device. It allows the assigning/releasing of resources into/from Subarray, configuring capabilities, and exposes the related information like assigned resources, configured capabilities, etc.

Device Class¶

class ska_tango_base.SKASubarray(*args: Any, **kwargs: Any)[source]¶

Implements the SKA SubArray device

class InitCommand(target, state_model, logger=None)[source]¶

A class for the SKASubarray’s init_device() “command”.

Create a new InitCommand

Parameters

target (object) – the object that this command acts upon; for example, the SKASubarray device for which this class implements the command
state_model (DeviceStateModel) – the state model that this command uses to check that it is allowed to run, and that it drives with actions.
logger (a logger that implements the standard library logger interface) – the logger to be used by this Command. If not provided, then a default module logger will be used.

do()[source]¶

Stateless hook for device initialisation.

Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

class AssignResourcesCommand(target, state_model, logger=None)[source]¶

A class for SKASubarray’s AssignResources() command.

Constructor for AssignResourcesCommand

Parameters

target (object) – the object that this command acts upon; for example, the SKASubarray device for which this class implements the command
state_model (SKASubarrayStateModel) – the state model that this command uses to check that it is allowed to run, and that it drives with actions.
logger (a logger that implements the standard library logger interface) – the logger to be used by this Command. If not provided, then a default module logger will be used.

do(argin)[source]¶

Stateless hook for AssignResources() command functionality.

Parameters: argin (list of str) – The resources to be assigned
Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

class ReleaseResourcesCommand(target, state_model, logger=None)[source]¶

A class for SKASubarray’s ReleaseResources() command.

Constructor for OnCommand()

Parameters

target (object) – the object that this command acts upon; for example, the SKASubarray device for which this class implements the command
state_model (SKASubarrayStateModel) – the state model that this command uses to check that it is allowed to run, and that it drives with actions.
logger (a logger that implements the standard library logger interface) – the logger to be used by this Command. If not provided, then a default module logger will be used.

do(argin)[source]¶

Stateless hook for ReleaseResources() command functionality.

Parameters: argin (list of str) – The resources to be released
Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

class ReleaseAllResourcesCommand(target, state_model, logger=None)[source]¶

A class for SKASubarray’s ReleaseAllResources() command.

Constructor for OnCommand()

Parameters

target (object) – the object that this command acts upon; for example, the SKASubarray device for which this class implements the command
state_model (SKASubarrayStateModel) – the state model that this command uses to check that it is allowed to run, and that it drives with actions.
logger (a logger that implements the standard library logger interface) – the logger to be used by this Command. If not provided, then a default module logger will be used.

do()[source]¶

Stateless hook for ReleaseAllResources() command functionality.

Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

class ConfigureCommand(target, state_model, logger=None)[source]¶

A class for SKASubarray’s Configure() command.

Constructor for ConfigureCommand

Parameters

target (object) – the object that this command acts upon; for example, the SKASubarray device for which this class implements the command
state_model (SKASubarrayStateModel) – the state model that this command uses to check that it is allowed to run, and that it drives with actions.
logger (a logger that implements the standard library logger interface) – the logger to be used by this Command. If not provided, then a default module logger will be used.

do(argin)[source]¶

Stateless hook for Configure() command functionality.

Parameters: argin (str) – The configuration as JSON
Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

class ScanCommand(target, state_model, logger=None)[source]¶

A class for SKASubarray’s Scan() command.

Constructor for ScanCommand

Parameters

target (object) – the object that this command acts upon; for example, the SKASubarray device for which this class implements the command
state_model (SKASubarrayStateModel) – the state model that this command uses to check that it is allowed to run, and that it drives with actions.
logger (a logger that implements the standard library logger interface) – the logger to be used by this Command. If not provided, then a default module logger will be used.

do(argin)[source]¶

Stateless hook for Scan() command functionality.

Parameters: argin (str) – Scan info
Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

class EndScanCommand(target, state_model, logger=None)[source]¶

A class for SKASubarray’s EndScan() command.

Constructor for EndScanCommand

Parameters

target (object) – the object that this command acts upon; for example, the SKASubarray device for which this class implements the command
state_model (SKASubarrayStateModel) – the state model that this command uses to check that it is allowed to run, and that it drives with actions.
logger (a logger that implements the standard library logger interface) – the logger to be used by this Command. If not provided, then a default module logger will be used.

do()[source]¶

Stateless hook for EndScan() command functionality.

Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

class EndCommand(target, state_model, logger=None)[source]¶

A class for SKASubarray’s End() command.

Constructor for EndCommand

Parameters

target (object) – the object that this command acts upon; for example, the SKASubarray device for which this class implements the command
state_model (SKASubarrayStateModel) – the state model that this command uses to check that it is allowed to run, and that it drives with actions.
logger (a logger that implements the standard library logger interface) – the logger to be used by this Command. If not provided, then a default module logger will be used.

do()[source]¶

Stateless hook for End() command functionality.

Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

class AbortCommand(target, state_model, logger=None)[source]¶

A class for SKASubarray’s Abort() command.

Constructor for AbortCommand

Parameters

target (object) – the object that this command acts upon; for example, the SKASubarray device for which this class implements the command
state_model (SKASubarrayStateModel) – the state model that this command uses to check that it is allowed to run, and that it drives with actions.
logger (a logger that implements the standard library logger interface) – the logger to be used by this Command. If not provided, then a default module logger will be used.

do()[source]¶

Stateless hook for Abort() command functionality.

Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

class ObsResetCommand(target, state_model, logger=None)[source]¶

A class for SKASubarray’s ObsReset() command.

Constructor for ObsResetCommand

Parameters

target (object) – the object that this command acts upon; for example, the SKASubarray device for which this class implements the command
state_model (SKASubarrayStateModel) – the state model that this command uses to check that it is allowed to run, and that it drives with actions.
logger (a logger that implements the standard library logger interface) – the logger to be used by this Command. If not provided, then a default module logger will be used.

do()[source]¶

Stateless hook for ObsReset() command functionality.

Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

class RestartCommand(target, state_model, logger=None)[source]¶

A class for SKASubarray’s Restart() command.

Constructor for RestartCommand

Parameters

target (object) – the object that this command acts upon; for example, the SKASubarray device for which this class implements the command
state_model (SKASubarrayStateModel) – the state model that this command uses to check that it is allowed to run, and that it drives with actions.
logger (a logger that implements the standard library logger interface) – the logger to be used by this Command. If not provided, then a default module logger will be used.

do()[source]¶

Stateless hook for Restart() command functionality.

Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

init_command_objects()[source]¶: Sets up the command objects

CapabilityTypes = tango.server.device_property(dtype=('str',))¶

SubID = tango.server.device_property(dtype=str)¶

activationTime = tango.server.attribute(dtype=double, unit=s, standard_unit=s, display_unit=s, doc=Time of activation in seconds since Unix epoch.)¶: Device attribute.

assignedResources = tango.server.attribute(dtype=('str',), max_dim_x=100, doc=The list of resources assigned to the subarray.)¶: Device attribute.

configuredCapabilities = tango.server.attribute(dtype=('str',), max_dim_x=10, doc=A list of capability types with no. of instances in use on this subarray; e.g. Correlators:512, PssBeams:4, PstBeams:4, VlbiBeams:0.)¶: Device attribute.

always_executed_hook()[source]¶: Method that is always executed before any device command gets executed.

delete_device()[source]¶: Method to cleanup when device is stopped.

read_activationTime()[source]¶

Reads the time since device is activated.

Returns: Time of activation in seconds since Unix epoch.

read_assignedResources()[source]¶

Reads the resources assigned to the device.

Returns: Resources assigned to the device.

read_configuredCapabilities()[source]¶

Reads capabilities configured in the Subarray.

Returns: A list of capability types with no. of instances used in the Subarray

is_AssignResources_allowed()[source]¶

Check if command AssignResources is allowed in the current device state.

Raises: tango.DevFailed – if the command is not allowed
Returns: True if the command is allowed
Return type: boolean

AssignResources(argin)[source]¶

Assign resources to this subarray

To modify behaviour for this command, modify the do() method of the command class.

Parameters: argin (list of str) – the resources to be assigned
Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

is_ReleaseResources_allowed()[source]¶

Check if command ReleaseResources is allowed in the current device state.

Raises: tango.DevFailed – if the command is not allowed
Returns: True if the command is allowed
Return type: boolean

ReleaseResources(argin)[source]¶

Delta removal of assigned resources.

To modify behaviour for this command, modify the do() method of the command class.

Parameters: argin (list of str) – the resources to be released
Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

is_ReleaseAllResources_allowed()[source]¶

Check if command ReleaseAllResources is allowed in the current device state.

Raises: tango.DevFailed – if the command is not allowed
Returns: True if the command is allowed
Return type: boolean

ReleaseAllResources()[source]¶

Remove all resources to tear down to an empty subarray.

To modify behaviour for this command, modify the do() method of the command class.

Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

is_Configure_allowed()[source]¶

Check if command Configure is allowed in the current device state.

Raises: tango.DevFailed – if the command is not allowed
Returns: True if the command is allowed
Return type: boolean

Configure(argin)[source]¶

Configures the capabilities of this subarray

To modify behaviour for this command, modify the do() method of the command class.

Parameters: argin (string) – configuration specification
Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

is_Scan_allowed()[source]¶

Check if command Scan is allowed in the current device state.

Raises: tango.DevFailed – if the command is not allowed
Returns: True if the command is allowed
Return type: boolean

Scan(argin)[source]¶

Start scanning

To modify behaviour for this command, modify the do() method of the command class.

Parameters: argin (Array of str) – Information about the scan
Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

is_EndScan_allowed()[source]¶

Check if command EndScan is allowed in the current device state.

Raises: tango.DevFailed – if the command is not allowed
Returns: True if the command is allowed
Return type: boolean

EndScan()[source]¶

End the scan

To modify behaviour for this command, modify the do() method of the command class.

Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

is_End_allowed()[source]¶

Check if command End is allowed in the current device state.

Raises: tango.DevFailed – if the command is not allowed
Returns: True if the command is allowed
Return type: boolean

End()[source]¶

End the scan block.

To modify behaviour for this command, modify the do() method of the command class.

Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

is_Abort_allowed()[source]¶

Check if command Abort is allowed in the current device state.

Raises: tango.DevFailed – if the command is not allowed
Returns: True if the command is allowed
Return type: boolean

Abort()[source]¶

Abort any long-running command such as Configure() or Scan().

To modify behaviour for this command, modify the do() method of the command class.

Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

is_ObsReset_allowed()[source]¶

Check if command ObsReset is allowed in the current device state.

Raises: tango.DevFailed – if the command is not allowed
Returns: True if the command is allowed
Return type: boolean

ObsReset()[source]¶

Reset the current observation process.

To modify behaviour for this command, modify the do() method of the command class.

Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

is_Restart_allowed()[source]¶

Check if command Restart is allowed in the current device state.

Raises: tango.DevFailed – if the command is not allowed
Returns: True if the command is allowed
Return type: boolean

Restart()[source]¶

Restart the subarray. That is, deconfigure and release all resources.

To modify behaviour for this command, modify the do() method of the command class.

Returns: A tuple containing a return code and a string message indicating status. The message is for information purpose only.
Return type: (ResultCode, str)

Device State Model¶

class ska_tango_base.SKASubarrayStateModel(logger, op_state_callback=None, admin_mode_callback=None, obs_state_callback=None)[source]¶

Implements the state model for the SKASubarray

Initialises the model. Note that this does not imply moving to INIT state. The INIT state is managed by the model itself.

Parameters

logger (a logger that implements the standard library logger interface) – the logger to be used by this state model.
op_state_callback (callable) – A callback to be called when a transition implies a change to op state
admin_mode_callback (callable) – A callback to be called when a transition causes a change to device admin_mode
obs_state_callback (callable) – A callback to be called when a transition causes a change to device obs_state

Resource Manager¶

class ska_tango_base.SKASubarrayResourceManager[source]¶

A simple class for managing subarray resources

Constructor for SKASubarrayResourceManager

assign(resources)[source]¶

Assign some resources

Todo: Currently implemented for testing purposes to take a JSON string encoding a dictionary with key ‘example’. In future this will take a collection of resources.
Parameters: resources (JSON string) – JSON-encoding of a dictionary, with resources to assign under key ‘example’

release(resources)[source]¶

Release some resources

Todo: Currently implemented for testing purposes to take a JSON string encoding a dictionary with key ‘example’. In future this will take a collection of resources.
Parameters: resources (JSON string) – JSON-encoding of a dictionary, with resources to assign under key ‘example’

release_all()[source]¶: Release all resources

get()[source]¶

Get current resources

Returns: a set of current resources.
Return type: set of string