How to transform AWS lambda function for writing Timestream data to write Multi-measureme records

Question

I have a lambda function working to write measurement data to a Timestream table. The measurements each have a row in the Timestream table as this is the standard in Timestream. In nov 2021, AWS announced the Multi-Measure record functionality for Timestream tables. Because this would make my datastructure a lot simpler, I tried to transform the lambda function to do that.

I have a decoder.js file that takes care of putting a json payload with measurements of several remotely monitored generator sets (objects) in the right data structure before writing them to a Timestream table by the export handler in the index.js file. This is de code of de decoder function that works fine thus far (the runtime is Node.js 14.x):

function decodeMeasurement(payload, objectnr)

{
 var output = [];
 
 const dimensions = [{
   'Name': "genset_name",   
   'Value': payload.objects[objectnr].name.toString()
 },
 {
   'Name': 'imei',   
   'Value': payload.objects[objectnr].imei.toString()
 }];

 for (var variablenr = 0; variablenr < payload.objects[objectnr].variables.length; variablenr++){
   output.push ({
     'Dimensions': dimensions,
     'MeasureName': payload.objects[objectnr].variables[variablenr].name.toString(),
     'MeasureValue': payload.objects[objectnr].variables[variablenr].value.value.toString(),
     'MeasureValueType': 'DOUBLE',
     'Time': Date.parse(payload.objects[objectnr].variables[variablenr].value.date).toString()
    });
 
 }
    return (output);
}

I've tried to re-code this into the new MultiMeasurement Record structure, but it failed thusfar.

function decodeMeasurement(payload, objectnr)

{
 var output = [];
 console.log('The number of variables is:️ ', payload.objects[objectnr].variables.length);
 const dimensions = [{
   'Name': "genset_name",   
   'Value': payload.objects[objectnr].name.toString()
 },
 {
   'Name': 'imei',   
   'Value': payload.objects[objectnr].imei.toString()
 }];

 for (var variablenr = 0; variablenr < payload.objects[objectnr].variables.length; variablenr++){
   output.push ({
     'Dimensions': dimensions,
     'MeasureName': 'measurementvalues',
     'MeasureValueType': 'MULTI',
     'MeasureValues':{
       'Name': payload.objects[objectnr].variables[variablenr].name.toString(),
       'Value': payload.objects[objectnr].variables[variablenr].value.value.toString(),
       'Type': 'DOUBLE'},
     'Time': Date.parse(payload.objects[objectnr].variables[variablenr].value.date).toString()
    });
  }
    return (output);
}

I can't figure out what's wrong to the new code, I hope to get some tips that could make this work. Thanks!

Answer 1

Got it. Had to put the MeasureValues in an Array []. that worked!