Missing definition for DataloggerService2 SinkType

[danskorka]

In file protobuf/Services/DataLogger/SessionPropertyName.proto, the comment for SPN_SinkType reads

The type of sink used by the session. Must be of type <cref name="SinkType" /></summary>

However, no definition for SinkType is provided.

Should either provide definition, or comment should specify which core type and values to use.

[danskorka]

If I send a IDataLogger2ConfigureSessionRequest with a SessionProperty with name SPN_SinkType and value of ObjectType CT_Int32, I get a ConfigureSessionResponse with error code InvalidConfig.

logs/Output.log shows:
Arp.Services.DataLogger.Internal.Session ERROR - Session 'created_with_grpc': No SinkType provided for SinkProperties!

It seems the definition of SinkType is needed-

[martinboers]

Testing using grpcurl with AXC F 2152 FW 2025.6.

It's possible to successfully create a datalogger session:

$ grpcurl -insecure -format json -d '{"sessionName":"mysession", "persistent":"false"}' 192.168.1.10:50051 Arp.Services.DataLogger.Services.Grpc.IDataLoggerService2.CreateSession
{}

... and to successfully configure the datalogger session:

$ grpcurl -insecure -format json -d '{"sessionname":"mysession", "properties":{"Name":"SPN_SamplingInterval","Value":{"TypeCode":"CT_Int64","Int64Value":"2000000"}},"properties":{"Name":"SPN_PublishInterval","Value":{"TypeCode":"CT_Int64","Int64Value":"2000000"}},"properties":{"Name":"SPN_BufferCapacity","Value":{"TypeCode":"CT_Uint16","Uint16Value":"200"}},"properties":{"Name":"SPN_SinkType","Value":{"TypeCode":"CT_Int32","Int32Value":"2"}}}' 192.168.1.10:50051 Arp.Services.DataLogger.Services.Grpc.IDataLoggerService2.ConfigureSession
{}

... but the configuration never takes the value of the SPN_SinkType parameter:

$ grpcurl -insecure -format json -d '{"sessionname":"mysession"}' 192.168.1.10:50051 Arp.Services.DataLogger.Services.Grpc.IDataLoggerService2.GetSessionConfiguration
{
  "properties": [
    {
      "Name": "SPN_SamplingInterval",
      "Value": {
        "TypeCode": "CT_Int64",
        "Int64Value": "2000000"
      }
    },
    {
      "Name": "SPN_PublishInterval",
      "Value": {
        "TypeCode": "CT_Int64",
        "Int64Value": "2000000"
      }
    },
    {
      "Name": "SPN_BufferCapacity",
      "Value": {
        "TypeCode": "CT_Uint16",
        "Uint16Value": 200
      }
    },
    {
      "Name": 6,
      "Value": {
        "TypeCode": "CT_String",
        "StringValue": ""
      }
    },
    {
      "Name": "SPN_SinkType",
      "Value": {
        "TypeCode": "CT_Int32",
        "Int32Value": 1
      }
    }
  ]
}

Questions for the developers:

1. How can the SPN_SinkType parameter be set?
2. There is a parameter with the name "6". What does this represent?

[martinboers]

I now have answers to these questions from the gRPC server developers.

1. How can the SPN_SinkType parameter be set?

Here is an example of a valid datalogger session configuration, using a local gRPC client (the previous example used a remote client, which also works):

• Create a datalogger session:

grpcurl -format json -d '{"sessionName":"mysession", "persistent":"false"}' --plaintext unix:///run/plcnext/grpc.sock Arp.Services.DataLogger.Services.Grpc.IDataLoggerService2.CreateSession

• Configure the datalogger session with a Sink Type of "2" (i.e. persistent database):

grpcurl -format json -d '{"sessionname":"mysession", "properties":{"Name":"SPN_SamplingInterval","Value":{"TypeCode":"CT_Int64","Int64Value":"2000000"}},"properties":{"Name":"SPN_PublishInterval","Value":{"TypeCode":"CT_Int64","Int64Value":"2000000"}},"properties":{"Name":"SPN_BufferCapacity","Value":{"TypeCode":"CT_Uint16","Uint16Value":"200"}},"properties":{"Name":"SPN_SinkType","Value":{"TypeCode":"CT_Int32","EnumValue":"2"}},"properties":{"Name":"SPN_SinkProperties","Value":{"TypeCode":"CT_String","StringValue":"rollover=false;maxFiles=1;maxFileSize=5000000;storeChangesOnly=true;writeInterval=1000;dst=/opt/plcnext/RscClientDB.db;deleteRatio=5"}}}' --plaintext unix:///run/plcnext/grpc.sock Arp.Services.DataLogger.Services.Grpc.IDataLoggerService2.ConfigureSession

Notes:

• For some reason the Sink Type value must be specified with a Type Code of CT_Int32, but with an EnumValue (in this case, "2").
• When configuring a Sink Type of 2, Sink Properties must also be specified, otherwise the configuration will be rejected. The Sink Properties define the properties of the database file.

2. There is a parameter with the name "6". What does this represent?

This parameter represents the "Task Context". More recent firmware versions show the correct name for this parameter, rather than a number.

[danskorka]

@martinboers Thank you for your responses. I will have capacity to test this beginning of the next year. Happy holidays :-)

[danskorka]

Sorry for the long delay. I can confirm that this:

the Sink Type value must be specified with a Type Code of CT_Int32, but with an EnumValue (in this case, "2")

works.

I still feel that is a bug in the protbuf files.

[martinboers]

In firmware version 2026.6 it will be possible to se the Sink Type value with a Type Code of CT_Int32 and an Int32Value (rather than an EnumValue). This will then be consistent with the information about this parameter that has always been returned by the service:

       "Name": "SPN_SinkType",
      "Value": {
        "TypeCode": "CT_Int32",
        "Int32Value": 1
      }