By using AWS re:Post, you agree to the Terms of Use
/TwinMaker: using lambda to fetch data for non-timeSeries properties/

TwinMaker: using lambda to fetch data for non-timeSeries properties

0

Hello! I've been trying to use IoT RoboRunner + IoT TwinMaker + AWS Grafana to create a dashboard. As one of the most basic things to show is a list of the current workers/robots.

Take the following componentTypes: (parent, to be inherited from, to keep the lambda function common) Ideally, the lambda function would be able to see the event, and the associated telemetryAssetId, and reply with an appropriate payload.

{
  "componentTypeId": "com.example.lambda_reader",
  "workspaceId": "MyWorkspace",
  "functions": {
    "dataReader": {
      "implementedBy": {
        "lambda": {
          "arn": "arn:aws:lambda:us-east-1:<account>:function:RoboRunnerWorkerInfo"
        }
      }
    }
  },
  "propertyDefinitions": {
    "telemetryAssetId": {
      "dataType": {
        "type": "STRING"
      },
      "isExternalId": true,
      "isStoredExternally": false,
      "isTimeSeries": false,
      "isRequiredInEntity": true
    }
  }
}

and the child, which inherits from the above

{
    "componentTypeId": "com.example.myworkspace.worker_list",
    "extendsFrom": [
        "com.example.lambda_reader"
    ],
    "propertyDefinitions": {
        "telemetryAssetId": {
            "defaultValue" : { "stringValue": "WorkerList" }
        },
        "workerList": {
            "dataType": {
              "type": "LIST",
              "netstedType": {
                "type": "STRING"
              }
            },
            "isTimeSeries": false,
            "isStoredExternally": true
        }
    }
}

When adding these two componentTypes, the latter shows up as abstract unless isTimeSeries is set to true. Is this intended behavior? Seems like I should be able to do this? Any help is appreciated!

3 Answers
1

Hi, to explain little bit more into the detail, if a property is marked as IsStoredExternally means TwinMaker will only keep the property schema but not the value. So to access the property value you'll need to invoke the unified data access APIs with a defined connector.

For time-series property, you can use GetPropertyValueHistory API to access the property value, you need to define dataReader connector and while querying the property value in runtime, TwinMaker will forward the request to your connector to resolve it.

For non-time-series property, you can use GetPropertyValue API to access, and as you already found out, you need to define attributePropertyValueReaderByEntity connector for that.

We'll continue polishing our documentation to make it clear. Let us know if you are interested in more details on the topic.

Best,

answered 25 days ago
0
Accepted Answer

I was able to fetch non-timeseries properties by specifying a function under a different name than dataReader.

So, instead of

  "functions": {
    "dataReader": {
      "implementedBy": {
        "lambda": {
          "arn": "arn:aws:lambda:us-east-1:<account>:function:RoboRunnerWorkerInfo"
        }
      }
    }

for non-timeseries properties, it should be

  "functions": {
    "attributePropertyValueReaderByEntity": {
      "implementedBy": {
        "lambda": {
          "arn": "arn:aws:lambda:us-east-1:<account>:function:RoboRunnerWorkerInfo"
        }
      }
    }

Which is absolutely nowhere in the documentation. I arrived at it by sifting through github and finding https://github.com/aws-samples/aws-iot-twinmaker-samples/blob/main/src/modules/s3/component-types/s3_component_type.json

answered 25 days ago
-1

Are you unblocked?

answered a month ago
  • That really should have been a comment, not an answer

You are not logged in. Log in to post an answer.

A good answer clearly answers the question and provides constructive feedback and encourages professional growth in the question asker.

Guidelines for Answering Questions