Using Events

Using Events#

The design of the client, and the SDK in general, is synchronous. A synchronous design is generally preferred for automation scripts, but in some other cases, like a user interface, an asynchronous design can be preferable.

The SDK has no integration with any asynchronous library (such as asyncio or third-party libraries), but an optional event queue is offered to allow for custom integration.

Note

The Scrutiny GUI is built using QT. The SDK event queue is read in a thread and used to trigger QT signals, making the bridge between the synchronous and asynchronous worlds.

Example#

from scrutiny import sdk
from scrutiny.sdk.client import ScrutinyClient

client = ScrutinyClient()
client.listen_events(ScrutinyClient.Events.LISTEN_DEVICE_READY | ScrutinyClient.Events.LISTEN_DEVICE_GONE | ScrutinyClient.Events.LISTEN_DATALOGGER_STATE_CHANGED )
with client.connect('localhost', 8765):
    while True:
        event = client.read_event(timeout=0.5)
        if event is not None:
            if isinstance(event, ScrutinyClient.Events.DeviceReadyEvent):
                print(f"Device connected. Session ID : {event.session_id} ")
            elif isinstance(event, ScrutinyClient.Events.DeviceGoneEvent):
                print(f"Device has disconnected. Session ID : {event.session_id} ")
            elif isinstance(event, ScrutinyClient.Events.DataloggerStateChanged):
                if event.details.state == sdk.DataloggerState.DataReady:
                    print(f"Datalogging acquisition ready!")

Methods#

ScrutinyClient.listen_events(enabled_events, disabled_events=0)[source]#

Select which events are to be listen for when calling read_event.

Parameters:

  • enabled_events (int) – A flag value contructed by ORing values from ScrutinyClient.Events

  • disabled_events (int) –

Raises:

  • TypeError – Given parameter not of the expected type

  • ValueError – If the flag value is negative

Return type:

None

ScrutinyClient.read_event(timeout=None)[source]#

Read an event from the event queue using a blocking read operation

Parameters:

timeout (float | None) – Maximum amount of time to block. Blocks indefinetely if None

Returns:

The next event in the queue or None if there is no events after timeout is expired

Return type:

ConnectedEvent | DisconnectedEvent | DeviceReadyEvent | DeviceGoneEvent | SFDLoadedEvent | SFDUnLoadedEvent | DataloggerStateChanged | StatusUpdateEvent | None

class scrutiny.sdk.client.ScrutinyClient.Events#
class DataloggerStateChanged#

Triggered when the datalogger state changes or when the completion ratio is updated while acquiring

details: DataloggingInfo#

The state of the datalogger and the completion ratio

LISTEN_ALL = 4294967295#

Listen to all events

LISTEN_CONNECTED = 1#

Listen for events of type ConnectedEvent

LISTEN_DATALOGGER_STATE_CHANGED = 64#

Listen for events of type DataloggerStateChanged

LISTEN_DEVICE_GONE = 8#

Listen for events of type DeviceGoneEvent

LISTEN_DEVICE_READY = 4#

Listen for events of type DeviceReadyEvent

LISTEN_DISCONNECTED = 2#

Listen for events of type DisconnectedEvent

LISTEN_NONE = 0#

Listen to no events

LISTEN_SFD_LOADED = 16#

Listen for events of type SFDLoadedEvent

LISTEN_SFD_UNLOADED = 32#

Listen for events of type SFDUnLoadedEvent

LISTEN_STATUS_UPDATE_CHANGED = 128#

Listen for events of type DataloggerStateChanged

class StatusUpdateEvent#

Triggered when the a new server status is received

info: ServerInfo#

The status info received

Events#

class scrutiny.sdk.client.ScrutinyClient.Events.ConnectedEvent#

Triggered when the client connects to a Scrutiny server

host: str#

The server hostname

port: int#

The server port

class scrutiny.sdk.client.ScrutinyClient.Events.DisconnectedEvent#

Triggered when the client disconnects from a Scrutiny server

host: str#

The server hostname

port: int#

The server port

class scrutiny.sdk.client.ScrutinyClient.Events.DeviceReadyEvent#

Triggered when the server establish a communication with a device and the handshake phase is completed

session_id: str#

A unique ID assigned to the communication session. This ID will change if the same device disconnects and reconnects.

class scrutiny.sdk.client.ScrutinyClient.Events.DeviceGoneEvent#

Triggered when the the communication between the server and a device stops

session_id: str#

The unique ID assigned to the communication session.

class scrutiny.sdk.client.ScrutinyClient.Events.SFDLoadedEvent#

Triggered when the server loads a Scrutiny Firmware Description file, making Aliases and Variables available through the API

firmware_id: str#

The firmware ID that matches the SFD

class scrutiny.sdk.client.ScrutinyClient.Events.SFDUnLoadedEvent#

Triggered when the server unloads a Scrutiny Firmware Description file

firmware_id: str#

The firmware ID that matches the SFD

class scrutiny.sdk.client.ScrutinyClient.Events.DataloggerStateChanged#

Triggered when the datalogger state changes or when the completion ratio is updated while acquiring

details: DataloggingInfo#

The state of the datalogger and the completion ratio