MCT Serve realtime subscriptions should manage which channels are sent to each client <Cubesat Issue>

[mudinthewater]

The MCT adaptation for AIT-Core should manage connected clients with a dictionary of subscribed channels to minimize data throughput. This will allow one data source (the MCT server adapter) to receive all telemetry, but send minimal telemetry to each client, minimizing network usage.

[nttoole]

Refactored plugin now maintains set of subscribed telemetry points
This set is used to filter telemetry from AIT so that only subscribed telem is sent to the respective web-socket

For this test, we used the ait_simulate (from AIT-GUI) to add 1553_HS_Packet to the server.
Per the debug below, the plugin receives the packet with all fields, and then broadcasts to all-websockets.
Each web-socket subsets the telemetry to only include subscribe telem.
In this case, the OpenMCT client was displaying the Voltage_A telem:

Browser web-socket messages (indicates telem flowing from AIT OpenMct adaptation, note it contains a single field for the packet):

Plugin Debug (note incoming telem - which are broadcast to sessions - has all packet fields, but outgoing telem for specific socket is subset to subscribed fields only):

2022-03-24T11:45:55.589 | INFO     | AitOpenMctPlugin: Polling Telemetry queue...
2022-03-24T11:45:56.592 | INFO     | AitOpenMctPlugin: Broadcasting {'packet': '1553_HS_Packet', 'data': {'Voltage_A': 1, 'Voltage_B': 1, 'Voltage_C': 1, 'Voltage_D': 1, 'Current_A': -0.0008103727714748784}} to managed web-sockets...
2022-03-24T11:45:56.594 | INFO     | AitOpenMctPlugin: Sending realtime telemetry web-socket msg to websocket 2/140390135607024: {"packet": "1553_HS_Packet", "data": {"Voltage_A": 1}}

2022-03-24T11:45:56.595 | INFO     | AitOpenMctPlugin: Polling Telemetry queue...
2022-03-24T11:45:57.594 | INFO     | AitOpenMctPlugin: Broadcasting {'packet': '1553_HS_Packet', 'data': {'Voltage_A': 2, 'Voltage_B': 2, 'Voltage_C': 2, 'Voltage_D': 2, 'Current_A': 0.0}} to managed web-sockets...
2022-03-24T11:45:57.595 | INFO     | AitOpenMctPlugin: Sending realtime telemetry web-socket msg to websocket 2/140390135607024: {"packet": "1553_HS_Packet", "data": {"Voltage_A": 2}}

2022-03-24T11:45:57.596 | INFO     | AitOpenMctPlugin: Polling Telemetry queue...
2022-03-24T11:45:58.598 | INFO     | AitOpenMctPlugin: Broadcasting {'packet': '1553_HS_Packet', 'data': {'Voltage_A': 3, 'Voltage_B': 3, 'Voltage_C': 3, 'Voltage_D': 3, 'Current_A': 0.0008103727714748784}} to managed web-sockets...
2022-03-24T11:45:58.599 | INFO     | AitOpenMctPlugin: Sending realtime telemetry web-socket msg to websocket 2/140390135607024: {"packet": "1553_HS_Packet", "data": {"Voltage_A": 3}}

2022-03-24T11:45:58.600 | INFO     | AitOpenMctPlugin: Polling Telemetry queue...
2022-03-24T11:45:59.602 | INFO     | AitOpenMctPlugin: Broadcasting {'packet': '1553_HS_Packet', 'data': {'Voltage_A': 4, 'Voltage_B': 4, 'Voltage_C': 4, 'Voltage_D': 4, 'Current_A': 0.0016207455429497568}} to managed web-sockets...
2022-03-24T11:45:59.603 | INFO     | AitOpenMctPlugin: Sending realtime telemetry web-socket msg to websocket 2/140390135607024: {"packet": "1553_HS_Packet", "data": {"Voltage_A": 4}}