Retrieves your YouTube video run-time, in hours, using dependency-free PowerShell code

Get-YouTubeVideoRuntime.ps1

$ErrorActionPreference = 'stop'

function Get-YouTubeChannel {
  [CmdletBinding()]
  param (
    [Parameter(Mandatory = $true)]
    [string] $Username,
    [Parameter(Mandatory = $true)]
    [string] $AccessToken
  )
  $Uri = 'https://www.googleapis.com/youtube/v3/channels?part=contentDetails&forUsername={1}&access_token={0}' -f $AccessToken, $Username
  Invoke-RestMethod -Uri $Uri
}

function Get-YouTubePlaylistItems {
  [CmdletBinding()]
  [OutputType([String[]])]
  param (
    [Parameter(Mandatory = $true)]
    [string] $PlaylistId,
    [Parameter(Mandatory = $true)]
    [string] $AccessToken
  )

  $VideoIdList = [System.Collections.ArrayList]::new()
  $NextPageToken = ''
  
  do {
    $Result = Invoke-RestMethod -Uri ('https://www.googleapis.com/youtube/v3/playlistItems?pageToken={2}&part=contentDetails&maxResults=50&playlistId={1}&access_token={0}' -f $AccessToken, $PlaylistId, $NextPageToken)
    $NextPageToken = $Result.nextPageToken
    if ($NextPageToken) { Write-Verbose -Message $NextPageToken }
  
    foreach ($Video in $Result.items) {
      $null = $VideoIdList.Add($Video.contentDetails.videoId)
    }
  } while ($Result.nextPageToken)
  
  return $VideoIdList
}

function Get-YouTubeVideoDetail {
  [CmdletBinding()]
  param (
    [Parameter(Mandatory = $true)]
    [System.Collections.ArrayList] $Id,
    [Parameter(Mandatory = $true)]
    [string] $AccessToken
  )

  function Add-DurationSecondsProperty {
    [CmdletBinding()]
    param (
      [Parameter(ValueFromPipeline = $true)]
      $Object
    )
    process {
      $input | Add-Member -PassThru -MemberType ScriptProperty -Name DurationSeconds -Value {
        $RegEx = 'PT(?<Minutes>\d+)M(?<Seconds>\d+)S|PT(?<Seconds>\d+)S|PT(?<Minutes>\d+)M'
        $Matched = $this.contentDetails.duration -match $RegEx
        if ($Matched) {
          $Minutes = [int]$Matches['Minutes']
          $Seconds = [int]$Matches['Seconds']
          return ($Minutes*60) + $Seconds
        }
        else { return 0 }
      }
    }
  }

  $VideoDetailList = [System.Collections.ArrayList]::new()
  $NextPageToken = ''

  for ($i = 0; $i -lt $Id.Count; $i += 50) {
    $ItemCount = if (($Id.Count - $i) -gt 50) { 50 } else { $Id.Count - $i }
    Write-Verbose -Message $ItemCount
    $Uri = 'https://www.googleapis.com/youtube/v3/videos?part=contentDetails&pageToken={2}&maxResults=50&id={1}&access_token={0}' -f $AccessToken, ($Id.GetRange($i, $ItemCount) -join ','), $NextPageToken
    Write-Verbose -Message $Uri
    $VideoDetailResult = Invoke-RestMethod -Uri $Uri
    $null = $VideoDetailList.AddRange(($VideoDetailResult.items | Add-DurationSecondsProperty))
    $NextPageToken = $VideoDetailResult.nextPageToken
  }

  return $VideoDetailList
}

# Use the Google oAuth Playground to obtain an access token.
# Make sure the token is generated, with the appropriate oAuth scope for YouTube Data API v3.
# I tested it with just this oAuth scope: https://www.googleapis.com/auth/youtube
$Token = 'PutYourAccessTokenHere'
$Username = 'PutYourYouTubeUsernameHere'

$Channel = Get-YouTubeChannel -Username $Username -AccessToken $Token
$VideoIdList = Get-YouTubePlaylistItems -PlaylistId $Channel.items[0].contentDetails.relatedPlaylists.uploads -AccessToken $Token
$VideoDetailResult = Get-YouTubeVideoDetail -Id $VideoIdList -AccessToken $Token -Verbose

# Result will be the number of hours of play-time
($VideoDetailResult.DurationSeconds | Measure-Object -Sum).Sum/60/60