Converting Fitbit Weight Measurement Data to Withings Import Format

Convert-FitbitToWithingsWeightMeasurements.ps1

Function Convert-FitbitToWithingsWeightMeasurements {
  [CmdletBinding()]
  Param(
    [Parameter()]
    [String]
    $Folder =(Get-Location).Path
  )

  # Create a collection (a List for memory efficiency) to hold output
  $WithingsWeightMeasurements = New-Object System.Collections.Generic.List[System.Object]

  # Search for all files that start with weight and end with .json
  $JsonFilesCount = 0
  $WeightMeasurementsCount = 0
  Get-ChildItem $Folder -Filter weight-*.json |
  Foreach-Object {
    $JsonFilesCount += 1
    # Get JSON content and then add them to the collection
    Get-Content $_.FullName | Out-String | ConvertFrom-Json | ForEach-Object {
      $WeightMeasurementsCount += 1
      $WithingsWeightMeasurements.Add([PSCustomObject]@{
        Date = $([DateTime]$_.date).ToString('yyyy-MM-dd') + " " + $([DateTime]$_.time).ToString("hh:mm:ss")
        Weight = $_.weight
        FatMass = if($_.fat -le 1) {""} else {[Math]::Round(($_.weight * ($_.fat / 100)),2)}
      }) | Out-Null
      # - Date must be in yyyy-mm-dd hh:mm:ss format (example: 2013-11-22 08:35:00)
      # - Values must be in US numbers format (with a point as decimal mark)
      # - Numerical values must be in the same unit set in your dashboard
      # - Fat mass (optional - format : kg) (OR 'lb' based on "same unit set in your dashboard")
      # Fat isn't always available from Fitbit either
    }
  }

  # - Do not exceed 300 rows in a file
  # Split to 299 value arrays
  $ImportSizeLimit = 299

  Write-Host "Captured $WeightMeasurementsCount weight measurements from $JsonFilesCount exported Fitbit files. Splitting data to $ImportSizeLimit batches for import."

  $WeightMeasurementImportFiles = New-Object System.Collections.ArrayList
  $WeightItemsTemp = New-Object System.Collections.ArrayList
  $WithingsWeightMeasurements | ForEach-Object {
    $WeightItemsTemp.Add($_) | Out-Null
    If ($WeightItemsTemp.Count -ge $ImportSizeLimit) {
      $WeightMeasurementImportFiles.Add($WeightItemsTemp.ToArray()) | Out-Null
      $WeightItemsTemp.Clear()
    }
  }

  # Capture the last set of items
  if ($WeightItemsTemp.Count -gt 0) {
    $WeightMeasurementImportFiles.Add($WeightItemsTemp.ToArray()) | Out-Null
    $WeightItemsTemp.Clear()
  }

  # Create output folder
  $OutputFolder = Join-Path -Path (Get-Location).Path -ChildPath "FilesToImport"
  If (-Not (Test-Path -Path $OutputFolder)) {
    Write-Host "- Creating folder for generated files at $OutputFolder"
    New-Item -Path $OutputFolder -ItemType Directory | Out-Null
  }

  # Write each file
  for ($i = 0; $i -lt $WeightMeasurementImportFiles.Count; $i++) {
    $WeightMeasurementImportFilePath = Join-Path -Path $OutputFolder -ChildPath "Withings-Weight-Import-$i.csv"
    Write-Host "- Exporting $($i+1)/$($WeightMeasurementImportFiles.Count) weight measurement import batches to $WeightMeasurementImportFilePath."
    # - File must have a header
    # - File must be in a CSV format with commas as column separators and without field separators
    $WeightMeasurementImportFiles[$i] | Export-Csv $WeightMeasurementImportFilePath -NoTypeInformation -Force -Delimiter ',' -UseQuotes Never
  }

  Write-Host "Conversion of Fitbit data complete. Please see instructions at https://support.withings.com/hc/en-us/articles/201491477-Health-Mate-Online-Dashboard-Importing-data for importing."

}

output.txt

PS /code/FitbitToWithingsWeightConversion> . ./Convert-FitbitToWithingsWeightMeasurements.ps1
PS /code/FitbitToWithingsWeightConversion> Convert-FitbitToWithingsWeightMeasurements ./ImportDataOriginal/
Captured 1898 weight measurements from 82 exported Fitbit files. Splitting data to 299 batches for import.
- Exporting 1/7 weight measurement import batches to /Users/rob/code/mine/FitbitToWithingsWeightConversion/FilesToImport/Withings-Weight-Import-0.csv.
- Exporting 2/7 weight measurement import batches to /Users/rob/code/mine/FitbitToWithingsWeightConversion/FilesToImport/Withings-Weight-Import-1.csv.
- Exporting 3/7 weight measurement import batches to /Users/rob/code/mine/FitbitToWithingsWeightConversion/FilesToImport/Withings-Weight-Import-2.csv.
- Exporting 4/7 weight measurement import batches to /Users/rob/code/mine/FitbitToWithingsWeightConversion/FilesToImport/Withings-Weight-Import-3.csv.
- Exporting 5/7 weight measurement import batches to /Users/rob/code/mine/FitbitToWithingsWeightConversion/FilesToImport/Withings-Weight-Import-4.csv.
- Exporting 6/7 weight measurement import batches to /Users/rob/code/mine/FitbitToWithingsWeightConversion/FilesToImport/Withings-Weight-Import-5.csv.
- Exporting 7/7 weight measurement import batches to /Users/rob/code/mine/FitbitToWithingsWeightConversion/FilesToImport/Withings-Weight-Import-6.csv.
Conversion of Fitbit data complete. Please see instructions at https://support.withings.com/hc/en-us/articles/201491477-Health-Mate-Online-Dashboard-Importing-data for importing.

This was to get my data into Withings and subsequently into Health. I posted this over at https://support.withings.com/hc/en-us/community/posts/360031291453-Import-Fitbit-Aria-Scale-Info.