Infos

This page lists all the Infos that are defined internal to Malcolm. Note that Malcolm enabled support modules may add their own Info derived classes.

Each module may define Infos for use in the parts it defines or in other module’s parts hosted in the controllers it defines.

builtin module Infos

class malcolm.modules.builtin.infos.LabelInfo(label: str)

Used to tell the Controller the label of the Block should change

Parameters:label – The new title of the Block

class malcolm.modules.builtin.infos.HealthInfo(alarm: malcolm.core.alarm.Alarm, ts: malcolm.core.timestamp.TimeStamp = None)

Used to tell the Controller a part has an alarm or not

Parameters:alarm – The alarm that should be used for the health of the block

class malcolm.modules.builtin.infos.PortInfo(name: str, port: malcolm.core.tags.Port)

Info about a port to be used by other child parts for connection

Parameters:

• name – The name of the attribute
• port – The type of the port

class malcolm.modules.builtin.infos.SinkPortInfo(name: str, port: malcolm.core.tags.Port, disconnected_value: str, value: Any)

Info about a Sink Port from the attribute tag

Parameters:

• name – The name of the attribute
• port – The type of the port
• disconnected_value – The value that will be set when the Sink port is disconnected, E.g. ‘’ or ‘ZERO’
• value – Initial value of the attribute

class malcolm.modules.builtin.infos.SourcePortInfo(name: str, port: malcolm.core.tags.Port, connected_value: str)

Info about a Source Port from the attribute tag

Parameters:

• name – The name of the attribute
• port – The type of the port
• connected_value – The value that a Sink Port will be set to when connected to this Source Port, E.g. ‘PCOMP1.OUT’ or ‘DET.STATS’

class malcolm.modules.builtin.infos.LayoutInfo(mri: str, x: float, y: float, visible: bool)

Info about the position and visibility of a child block in a layout

Parameters:

• mri – Malcolm full name of child block
• x – X Coordinate of child block
• y – Y Coordinate of child block
• visible – Whether child block is visible

class malcolm.modules.builtin.infos.PartExportableInfo(names: Sequence[str], port_infos: List[malcolm.modules.builtin.infos.PortInfo])

Info about the exportable fields and port infos for a Part

Parameters:

• names – The list of fields that the Part thinks are exportable
• port_infos – The list of PortInfo objects that the Part exposes

class malcolm.modules.builtin.infos.PartModifiedInfo(modified: Dict[str, str])

Info about whether the part was modified or not

Parameters:modified – {attr_name: message} for all attributes that have been modified from the saved value

class malcolm.modules.builtin.infos.RequestInfo(request: malcolm.core.request.Request, mri: str)

Info saying that the part has received a request that needs servicing. Reporting this will send to the correct controller, but not wait for completion

Parameters:

• request – The request that needs servicing, with callback filled in
• mri – The mri of the controller that should handle it

scanning module Infos

These are used by parts hosted in a RunnableController

class malcolm.modules.scanning.infos.DatasetType

NeXus type of a produced dataset

PRIMARY = 'primary'

Detector data, like the 2D data from an imaging detector

SECONDARY = 'secondary'

Calculated from detector data, like the sum of each frame

MONITOR = 'monitor'

Data that only makes sense when considered with detector data, like a measure of beam current with an ion chamber

POSITION_SET = 'position_set'

The demand positions of an axis as specified by the generator

POSITION_VALUE = 'position_value'

The readback positions of an axis that moves during the scan

POSITION_MIN = 'position_min'

The minimum value of the readback position of an axis in each frame

POSITION_MAX = 'position_max'

The maximum value of the readback position of an axis in each frame

class malcolm.modules.scanning.infos.ParameterTweakInfo(parameter: str, value: Any)

Info about a configure() parameter that needs to be tweaked

Parameters:

• parameter – Parameter name, e.g. “generator”
• value – The value it should be changed to

class malcolm.modules.scanning.infos.ConfigureParamsInfo(metas: Dict[str, malcolm.core.models.VMeta], required: List[str], defaults: Dict[str, Any])

Info about the parameters that should be passed to the Part in configure. The Controller will validate these when Block.configure() is called, and pass them to all Parts that have registered interest in them.

Parameters:

• metas – Metas for the extra parameters
• required – List of required parameters
• defaults – Default values for parameters

class malcolm.modules.scanning.infos.RunProgressInfo(steps: int)

Info about how far the current run has progressed

Parameters:steps – The number of completed steps

class malcolm.modules.scanning.infos.MinTurnaroundInfo(gap: float, interval: float)

Info about the minimum time gap that should be left between points that are not joined together

Parameters:

• gap – The minimum time gap in seconds
• interval – the minimum interval between two turnaround points

class malcolm.modules.scanning.infos.DatasetProducedInfo(name: str, filename: str, type: malcolm.modules.scanning.infos.DatasetType, rank: int, path: str, uniqueid: str)

Declare that we will write the following dataset to file

Parameters:

• name – Dataset name
• filename – Filename relative to the fileDir we were given
• type – What NeXuS dataset type it produces
• rank – The rank of the dataset including generator dims
• path – The path of the dataset within the file
• uniqueid – The path of the UniqueID dataset within the file

class malcolm.modules.scanning.infos.MotionTrigger

Request from a trigger source to the motion controller of what triggers it needs

NONE = 0

No Triggers required

ROW_GATE = 1

Trigger that spans each continuous joined section

EVERY_POINT = 2

One trigger for each point

class malcolm.modules.scanning.infos.MotionTriggerInfo(trigger: malcolm.modules.scanning.infos.MotionTrigger)

Declare that we need triggers of a certain sort from the motor controller

Parameters:trigger – What type is required

class malcolm.modules.scanning.infos.DetectorMutiframeInfo(mri: str)

Declare that we are able to produce mutiple frames per point for this detector

Parameters:mri – The mri of the detector in the DetectorTable

class malcolm.modules.scanning.infos.ExposureDeadtimeInfo(readout_time: float, frequency_accuracy: float, min_exposure: float)

Detector exposure time should be generator.duration - deadtime

Parameters:

• readout_time – The per frame readout time of the detector
• frequency_accuracy – The crystal accuracy in ppm
• min_exposure – The minimum exposure time this detector supports

calculate_exposure(duration: float, exposure: float = 0.0) → float

Calculate the exposure to set the detector to given the duration of the frame and the readout_time and frequency_accuracy

web module Infos

These are used by parts hosted in a HTTPServerComms.

class malcolm.modules.web.infos.HandlerInfo(regexp: str, request_class: Type[<MagicMock name='mock.RequestHandler' id='139916663443664'>], **kwargs)

Tornado RequestHandlers that should make up the webserver application

Parameters:

• regex – Path for this handler to get requests from. E.g. r”/ws”
• request_class – Request handler to instantiate for this
• **kwargs – Keyword args to be passed to request_class constructor