Session Basics

Sessions are a logical way to organise telemetry — like a file system.

An RTA Session does not have to be a 1:1 match for a telemetry recording, and there is no prescribed file or database layout. An RTA service can present any bounded subset of telemetry as a session, with associated metadata and descriptors.

JSON

The RTA API represents sessions in JSON, like this:

{
    "sessions": [
        {
            "identity": "f10f4a19-3831-4dd6-a178-faa94931a5b0",
            "state": "closed",
            "timestamp": "2021-05-06T18:58:56.20289+01:00",
            "startTimestamp": "2021-05-06T18:58:56.20289+01:00",
            "endTimestamp": "2021-05-06T19:08:56.20289+01:00",
            "timeRange": {
                "startTime": 1620323936202890000,
                "endTime": 1620324536202890000
            },
            "identifier": "Session Demo 06 May 2021 18:58",
            "details": {
                "Lab Tech": "Bob Jones",
                "Run": 17
            },
            "configBindings": [
                {
                    "identifier": "6d711dbc-5f0d-47d2-b127-8c9d20bcec01",
                    "channelOffset": 0
                }
            ]
        }
    ]
}

Review the Session Model for more detail.

C# Sample

The Toolkit Session Service provides an API to create and modify sessions using gRPC.

This C# sample — using the MAT.OCS.RTA.Toolkit.API.GrpcClients NuGet Package — produces an equivalent result:

// re-use the channel across service calls
using var sessionChannel = GrpcChannel.ForAddress("http://localhost:2652");
var sessionClient = new SessionStore.SessionStoreClient(sessionChannel);

await sessionClient.CreateOrUpdateSessionAsync(new CreateOrUpdateSessionRequest
{
    Identity = "f10f4a19-3831-4dd6-a178-faa94931a5b0",
    CreateIfNotExists = new()
    {
        Identifier = "Session Demo 06 May 2021 18:58",
        Timestamp = "2021-05-06T18:58:56.20289+01:00",
        State = (int)SessionState.Closed
    },
    Updates =
    {
        new SessionUpdate
        {
            SetTimeRange = new()
            {
                StartTime = 1620323936202890000,
                EndTime = 1620324536202890000
            }
        },
        new SessionUpdate
        {
            SetDetailsJson = new()
            {
                Json = new JObject
                {
                    ["Lab Tech"] = "Bob Jones",
                    ["Run"] = 17
                }.ToString()
            }
        },
        new SessionUpdate
        {
            SetConfigBindings = new()
            {
                ConfigBindings =
                {
                    new ConfigBinding
                    {
                        Identifier = "6d711dbc-5f0d-47d2-b127-8c9d20bcec01"
                    }
                }
            }
        }
    }
});