How to copy file for one time a day - elegant solution - powershell

Question

I have remote server, where will be uploaded one file per day. I don't know when the file will be uploaded. I need to COPY this file to another server for processing and I need to do this just once per file (once a day). When the file is uploaded on remote server, I need to copy it within a hour, so I have to run this script at least once per hour. I'm using this script:
# Get yesterday date
$date = (Get-Date).Adddays(-1) | Get-Date -Format yyyyMMdd
$check = ""
$check = Get-Content c:\checkiftransfered.txt
# Test if file checkiftransfered.txt contains True or False. If it contains True, file for this day was already copyied
if ($check -ne "True") {
#Test if file exists - it has specific name and yesterday date
if(Test-Path \\remoteserver\folder\abc_$date.xls) {
Copy-Item \\remoteserver\folder\abc_$date.xls \\remoteserver2\folder\abc_$date.xls
# Write down information that file was already copyied
$check = "True" | Out-File c:\checkiftransfered.txt
} else { Write-Host "File has not been uploaded."}
} else { Write-Host "File has been copyied."}
# + I will need another script that will delete the checkiftransfered.txt at 0:00
It will work fine, I think, but I'm looking for more elegant solution - the best way how to solve it. Thank you

Answer 1

In PowerShell V3, Test-Path has a handy -NewerThan and -OlderThan parameters so you could simplify to this:
$yesterday = (Get-Date).AddDays(-1)
$date = $yesterday | Get-Date -Format yyyyMMdd
$path = "\\remoteserver\folder\abc_$date.xls"
if (Test-Path $path -NewerThan $yesterday)
{
Copy-Item $path \\remoteserver2\folder\abc_$date.xls -Verbose
(Get-Item $path).LastWriteTime = $yesterday
}
This eliminates the need to track copy status in a separate by using the LastWriteTime. One note about using -NewerThan and -OlderThan - don't use them together. It doesn't work as expected.
And lest we forget about some great native tools, here's a solution using robocopy:
robocopy $srcdir $destdir /maxage:1 /mot:60
The /mot:n option will cause robocopy to continuously monitor the source dir - every 60 minutes as specified above.

Answer 2

There is a much, much easier and more reliable way. You can use the FileSystemWatcher class.
$watcher = New-Object System.IO.FileSystemWatcher
$watcher.Path = 'C:\Uploads'
$watcher.IncludeSubdirectories = $true
$watcher.EnableRaisingEvents = $true
$created = Register-ObjectEvent $watcher "Created" -Action {
Sleep (30*60)
Copy-Item $($eventArgs.FullPath) '\\remoteserver2\folder\'
}
So lets take a look at what we doing here, we create a new watcher and tell it to watch C:\Uploads when a new file is uploaded there the file system sends a notification through the framework to our program, which in turn fires the created event. When that happens, we tell our program to sleep to for 30 minutes to allow the upload to finish (that may be to long depending on the size of the upload) then we call Copy-Item on the event arguments which contains a full path to our new file.
By the way you would need to paste this in a powershell window and leave it open on the server, alternatively you could use the ISE and leave that open. Either way it is way more reliable that what you currently have.