Powershell script that uses the gmail-backup.com cmd line tool to download emails from gmail in chunks of X days and store them in separate folders

gmail-backup.ps1

## usage
## Download gmail-backup from www.gmail-backup.com and put it under "tools" folder relative to the script
## The idea is to download emails in small batches to avoid network issues and make a re-start easier. It also helps to avoid huge folders
## INPUT: the storage folder, amount of days to make the cut, start date, end date, credentials
## EXAMPLE:
## new-backup "d:\mail" 30 (get-date -year 2004 -month 01 -day 01) (get-date -y 2006 -month 01 -day 01) "youremail" "yourpwd"

function log($msg) {
  $msg = (get-date).ToString("yyyyMMdd hh:mm:ss") + " $msg"
  add-content log.txt $msg
}

function new-backup($rootFolder, $daysBatch, $start, $end, $mail, $pwd) {
  $from = $start  
  do {
    $to = $from.AddDays($daysBatch)      
    $fromFormatted = $from.ToString("yyyyMMdd")
    $toFormatted = $to.ToString("yyyyMMdd")
    $path = [System.IO.Path]::Combine($rootFolder, "$fromFormatted-$toFormatted")
    if (-not (test-path $path)) {
      $newPath = new-item -path $path -type directory
      write-host "Backing up $fromFormatted to $toFormatted"
      write-host "NOTE: if you want to see the progress, open log.txt"
      log "Starting backup of $fromFormatted to $toFormatted"
      $execPath = [System.IO.Path]::Combine((Get-Location), "tool\gmail-backup.exe")      
      $params =  "backup $path $mail $pwd $fromFormatted $toFormatted"      
      start-process -FilePath $execPath -ArgumentList $params -RedirectStandardOutput temp.txt -Wait 
      add-content log.txt (get-content temp.txt)
      log "Finished backup of $fromFormatted to $toFormatted"
      remove-item temp.txt
    }
    
    $from = $to
  } while ($from -lt $end)   
}