csaxs_bec.devices.pseudo_devices.signal_forwarder.SignalForwarder#

class SignalForwarder(name, signal: str, device_manager=None, scan_info=None, **kwargs)[source]#

Bases: PSIPseudoDeviceBase

Forward one signal unchanged.

Initialize the PSI Device Base class.

Parameters:

name (str) – Name of the device
scan_info (ScanInfo) – The scan info to use.

Methods

`add_instantiation_callback`	Register a callback which will receive each OphydObject instance.
`cancel_on_stop`	Register a status object to be cancelled when the device is stopped.
`check_value`	Check if the value is valid for this object
`clear_sub`	Remove a subscription, given the original callback function
`complete`	Complete the device.
`configure`	Configure the device for something during a run
`describe`	Provide schema and meta-data for `read()`.
`describe_configuration`	Provide schema & meta-data for `read_configuration()`
`destroy`	Destroy the device.
`get`	Get the value of all components in the device
`get_device_tuple`	The device tuple type associated with an Device class
`get_instantiated_signals`	Yields all of the instantiated signals in a device hierarchy
`kickoff`	Kickoff the device.
`on_complete`	Called to inquire if a device has completed a scans.
`on_connected`	Called after the device is connected and its signals are connected.
`on_destroy`	Called when the device is destroyed.
`on_init`	Called when the device is initialized.
`on_kickoff`	Called to kickoff a device for a fly scan.
`on_pre_scan`	Called right before the scan starts on all devices automatically.
`on_stage`	Called while staging the device.
`on_stop`	Called when the device is stopped.
`on_trigger`	Called when the device is triggered.
`on_unstage`	Called while unstaging the device.
`pause`	Attempt to 'pause' the device.
`pre_scan`	Pre-scan function.
`put`	Put a value to all components of the device
`read`	Read data from the device.
`read_configuration`	Dictionary mapping names to value dicts with keys: value, timestamp
`resume`	Resume a device from a 'paused' state.
`set_defaults`	Set class-wide defaults for device communications
`stage`	Stage the device.
`stop`	Stop the device.
`subscribe`	Subscribe to events this event_type generates.
`summary`
`trigger`	Trigger the device.
`unstage`	Unstage the device.
`unsubscribe`	Remove a subscription
`unsubscribe_all`
`wait_for_condition`	Utility method to easily wait for signals or methods to reach an expected state.
`wait_for_connection`	Wait for connection of the pseudo device has to be called manually on BECProcessedSignals
`walk_components`	Walk all components in the Device hierarchy
`walk_signals`	Walk all signals in the Device hierarchy
`walk_subdevice_classes`	Walk all sub-Devices classes in the Device hierarchy
`walk_subdevices`	Walk all sub-Devices in the hierarchy

Attributes

`SUB_ACQ_DONE`
`SUB_DEVICE_MONITOR_1D`
`SUB_DEVICE_MONITOR_2D`
`SUB_DONE_MOVING`
`SUB_FILE_EVENT`
`SUB_MOTOR_IS_MOVING`
`SUB_PROGRESS`
`SUB_READBACK`
`SUB_VALUE`
`attr_name`
`component_names`
`configuration_attrs`
`connected`	If the device is connected.
`connection_timeout`
`destroyed`	Check if the device has been destroyed.
`dotted_name`	Return the dotted name
`event_types`	Events that can be subscribed to via `obj.subscribe`
`hints`
`kind`
`lazy_wait_for_connection`
`name`	name of the device
`parent`	The parent of the ophyd object.
`read_attrs`
`report`	A report on the object.
`root`	Walk parents to find ultimate ancestor (parent's parent...).
`signal`	A descriptor representing a device component (or signal)
`signal_names`
`staged`	Check if the device has been staged.
`stopped`	Check if the device has been stopped.
`subscriptions`
`trigger_signals`

class OphydAttrList(device, kind, remove_kind, recurse_key)#

Bases: MutableSequence

list proxy to migrate away from Device.read_attrs and Device.config_attrs

append(value)#: S.append(value) – append value to the end of the sequence

clear() → None -- remove all items from S#

count(value) → integer -- return number of occurrences of value#

extend(values)#: S.extend(iterable) – extend sequence by appending elements from the iterable

index(value[, start[, stop]]) → integer -- return first index of value.#

Raises ValueError if the value is not present.

Supporting start and stop arguments is optional, but recommended.

insert(index, object)#: S.insert(index, value) – insert value before index

pop([index]) → item -- remove and return item at index (default last).#: Raise IndexError if list is empty or index is out of range.

remove(value)#: S.remove(value) – remove first occurrence of value. Raise ValueError if the value is not present.

reverse()#: S.reverse() – reverse IN PLACE

classmethod add_instantiation_callback(callback, fail_if_late=False)#

Register a callback which will receive each OphydObject instance.

Parameters:

callback (callable) – Expected signature: f(ophydobj_instance)
fail_if_late (boolean) – If True, verify that OphydObj has not yet been instantiated and raise RuntimeError if it has, as a way of verify that no instances will be “missed” by this registry. False by default.

cancel_on_stop(status: StatusBase) → None#

Register a status object to be cancelled when the device is stopped.

Parameters:: status (StatusBase) – The status object to be cancelled.

check_value(value, **kwargs)#

Check if the value is valid for this object

This function does no normalization, but may raise if the value is invalid.

Raises:: ValueError –

clear_sub(cb, event_type=None)#

Remove a subscription, given the original callback function

See also subscribe(), unsubscribe()

Parameters:

cb (callable) – The callback
event_type (str, optional) – The event to unsubscribe from (if None, removes it from all event types)

complete() → DeviceStatus | StatusBase#: Complete the device.

configure(d: Dict[str, Any]) → Tuple[Dict[str, Any], Dict[str, Any]]#

Configure the device for something during a run

This default implementation allows the user to change any of the configuration_attrs. Subclasses might override this to perform additional input validation, cleanup, etc.

Parameters:

d (dict) – The configuration dictionary. To specify the order that the changes should be made, use an OrderedDict.

Returns:

(old, new) tuple of dictionaries
Where old and new are pre- and post-configure configuration states.

property connected#

If the device is connected.

Subclasses should override this

describe() → OrderedDictType[str, Dict[str, Any]]#

Provide schema and meta-data for read().

This keys in the OrderedDict this method returns must match the keys in the OrderedDict return by read().

This provides schema related information, (ex shape, dtype), the source (ex PV name), and if available, units, limits, precision etc.

Returns:: data_keys – The keys must be strings and the values must be dict-like with the event_model.event_descriptor.data_key schema.
Return type:: OrderedDict

describe_configuration() → OrderedDictType[str, Dict[str, Any]]#

Provide schema & meta-data for read_configuration()

This keys in the OrderedDict this method returns must match the keys in the OrderedDict return by read().

This provides schema related information, (ex shape, dtype), the source (ex PV name), and if available, units, limits, precision etc.

Returns:: data_keys – The keys must be strings and the values must be dict-like with the event_model.event_descriptor.data_key schema.
Return type:: OrderedDict

destroy()#: Destroy the device.

property destroyed: bool#: Check if the device has been destroyed.

property dotted_name: str#: Return the dotted name

property event_types#: Events that can be subscribed to via obj.subscribe

get(**kwargs)#

Get the value of all components in the device

Keyword arguments are passed onto each signal.get(). Components beginning with an underscore will not be included.

classmethod get_device_tuple()#

The device tuple type associated with an Device class

This is a tuple representing the full state of all components and dynamic device sub-components.

get_instantiated_signals(*, attr_prefix=None)#

Yields all of the instantiated signals in a device hierarchy

Parameters:: attr_prefix (string, optional) – The attribute prefix. If None, defaults to self.name
Yields:: (fully_qualified_attribute_name, signal_instance)

kickoff() → DeviceStatus | StatusBase#: Kickoff the device.

property name#: name of the device

on_complete() → DeviceStatus | StatusBase | None#: Called to inquire if a device has completed a scans.

on_connected() → None#: Called after the device is connected and its signals are connected. Default values for signals should be set here.

on_destroy() → None#: Called when the device is destroyed. Cleanup resources here.

on_init() → None#

Called when the device is initialized.

No signals are connected at this point. If you like to set default values on signals, please use on_connected instead.

on_kickoff() → DeviceStatus | StatusBase | None#: Called to kickoff a device for a fly scan. Has to be called explicitly.

on_pre_scan() → DeviceStatus | StatusBase | None#: Called right before the scan starts on all devices automatically.

on_stage() → DeviceStatus | StatusBase | None#

Called while staging the device.

Information about the upcoming scan can be accessed from the scan_info (self.scan_info.msg) object.

on_stop() → None#: Called when the device is stopped.

on_trigger() → DeviceStatus | StatusBase | None#: Called when the device is triggered.

on_unstage() → DeviceStatus | StatusBase | None#: Called while unstaging the device.

property parent#

The parent of the ophyd object.

If at the top of its hierarchy, parent will be None

pause() → None#

Attempt to ‘pause’ the device.

This is called when ever the RunEngine is interrupted.

A device may have internal state that means plans can not safely be re-wound. This method may: put the device in a ‘paused’ state and/or raise NoReplayAllowed to indicate that the plan can not be rewound.

Raises:: bluesky.run_engine.NoReplayAllowed –

pre_scan() → DeviceStatus | StatusBase | None#: Pre-scan function.

put(dev_t, **kwargs)#

Put a value to all components of the device

Keyword arguments are passed onto each signal.put()

Parameters:: dev_t (DeviceTuple or tuple) – The device tuple with the value(s) to put (see get_device_tuple)

read() → OrderedDictType[str, Dict[str, Any]]#

Read data from the device.

This method is expected to be as instantaneous as possible, with any substantial acquisition time taken care of in trigger().

The OrderedDict returned by this method must have identical keys (in the same order) as the OrderedDict returned by describe().

By convention, the first key in the return is the ‘primary’ key and maybe used by heuristics in bluesky.

The values in the ordered dictionary must be dict (-likes) with the keys {'value', 'timestamp'}. The 'value' may have any type, the timestamp must be a float UNIX epoch timestamp in UTC.

Returns:: data – The keys must be strings and the values must be dict-like with the keys {'value', 'timestamp'}
Return type:: OrderedDict

read_configuration() → OrderedDictType[str, Dict[str, Any]]#

Dictionary mapping names to value dicts with keys: value, timestamp

To control which fields are included, change the Component kinds on the device, or modify the configuration_attrs list.

property report#: A report on the object.

resume() → None#

Resume a device from a ‘paused’ state.

This is called by the bluesky.run_engine.RunEngine when it resumes from an interruption and is responsible for ensuring that the device is ready to take data again.

property root#: Walk parents to find ultimate ancestor (parent’s parent…).

classmethod set_defaults(*, connection_timeout=10.0)#

Set class-wide defaults for device communications

This may be called only before any instances of Device are made.

This setting applies to the class it is called on and all its subclasses. For example,

>>> Device.set_defaults(...)

will apply to any Device subclass.

Parameters:: connection_timeout (float, optional) – Time (seconds) allocated for establishing a connection with the IOC.
Raises:: RuntimeError – If called after EpicsSignalBase has been instantiated for the first time.

stage() → list[object] | DeviceStatus | StatusBase#: Stage the device.

property staged: Staged#: Check if the device has been staged.

stop(*, success: bool = False) → None#

Stop the device.

Parameters:: success (bool) – True if the action was successful, False otherwise.

property stopped: bool#: Check if the device has been stopped.

subscribe(callback, event_type=None, run=True)#

Subscribe to events this event_type generates.

The callback will be called as cb(*args, **kwargs) with the values passed to _run_subs with the following additional keys:

sub_type : the string value of the event_type obj : the host object, added if ‘obj’ not already in kwargs

if the key ‘timestamp’ is in kwargs _and_ is None, then it will be replaced with the current time before running the callback.

The *args, **kwargs passed to _run_subs will be cached as shallow copies, be aware of passing in mutable data.

Warning

If the callback raises any exceptions when run they will be silently ignored.

Parameters:

callback (callable) –
A callable function (that takes kwargs) to be run when the event is generated. The expected signature is
```
def cb(*args, obj: OphydObject, sub_type: str, **kwargs) -> None:
```
The exact args/kwargs passed are whatever are passed to _run_subs
event_type (str, optional) –
The name of the event to subscribe to (if None, defaults to the default sub for the instance - obj._default_sub)

This maps to the sub_type kwargs in _run_subs
run (bool, optional) – Run the callback now