Retriable implementation in PowerShell completely ripped off from an implementation in Ruby.

retry.ps1

# complete rip off of http://blog.mirthlab.com/2012/05/25/cleanly-retrying-blocks-of-code-after-an-exception-in-ruby/
# 
# usage
#  retriable -tries 5 -action { do-work-that-could-throw-exception }
#

function retriable($tries=3, $interval=1, [scriptblock]$action)
{
  $retry_count = 1
  $the_exception = $null

  do
  {

    $is_error = $false


    try
    {
      & $action
      
      # reset in case it worked this last try
      #
      $is_error = $false
    }
    catch
    {
      #cache off exception to throw if we've exhausted our retries
      #
      $the_exception = $_
      
      $is_error = $true
      
      write-debug "[retriable] caught exception"   
      write-debug "[retriable] attempt $retry_count of $tries failed, trying again"
      
      if ( $retry_count -ge $tries )
      {
        write-debug "[retriable] exhausted $retry_count retry attempts"
      }
      else
      {
        write-debug "[retriable] waiting $interval seconds"
        sleep -seconds $interval
      }
      
    }

    $retry_count = $retry_count + 1
   
  }  while($is_error -eq $true -and $retry_count -le $tries)

  if ( $is_error )
  {
    throw $the_exception
  }
}