Download a file from the internet.

Get-WebFile.ps1

function Get-WebFile {
	<#
		.SYNOPSIS
			Download a file from the internet.

		.DESCRIPTION
			Download a file from the internet.

		.PARAMETER Url
			URL of file being downloaded

		.PARAMETER TargetPath
			Target path where the downloaded file will be saved. Defaults to the current folder.

		.PARAMETER Timeout
			Request timeout in milliseconds. Default is 100000.

		.EXAMPLE
			Get-WebFile http://some.server.com/file_to_download.zip

			Description
			-----------
			Download file_to_download.zip to the current folder

		.NOTES
			Name: Get-WebFile
			Author: Øyvind Kallstad
			Date: 26.02.2014
			Version: 1.0
	#>
	[CmdletBinding()]
	param(
		[Parameter(Mandatory = $true, Position = 0)]
		[string]$Url,

		[Parameter(Position = 1)]
		[ValidateScript({Test-Path $_ -PathType Container})]
		[string]$TargetPath = (Get-Location).Path,

		[Parameter()]
		[int]$Timeout
	)

	try{
		$target = Join-Path -Path $TargetPath -ChildPath (Split-Path -Leaf $url)

		# Create a web request object.
		$request = [System.Net.WebRequest]::Create($url)

		# Configure timeout if specified. Otherwise default value will be used.
		if($Timeout){
			$request.Timeout = $Timeout
			Write-Verbose "Request timeout set to $Timeout milliseconds"
		}

		# Get a response from the server
		$response = $request.GetResponse()
		if(-not($response.Server)){
			$server = ($response.ResponseUri.ToString()).Split("/")[2]
		}
		else{
			$server = $response.Server
		}

		# Check that the response is ok before continuing.
		if($response.StatusCode -ne 'OK'){
			Write-Warning "A problem occured. The server responded with the following code: $($response.StatusCode)"
			break
		}
		else{
			Write-Verbose "Got a response back from $server"
		}

		# Get a response stream from the server
		$responseStream = $response.GetResponseStream()

		# Check that we are able to read the stream before continuing
		if(-not($responseStream.CanRead)){
			Write-Warning 'Unable to read from server'
			break
		}

		# Set up a target stream. This will also create the destination file.
		$targetStream = New-Object -TypeName System.IO.FileStream -ArgumentList $target, Create
		Write-Verbose "Successfully created $target"

		# Set up a small buffer and start to read.
		$buffer = New-Object byte[] 10KB
		$read = $responseStream.Read($buffer,0,$buffer.length)

		# Take a note of the total downloaded bytes.
		$downloadedBytes = $read

		# As long as there are bytes that have have been read...
		while($read -gt 0){
			# ... write data to the destination file
			$targetStream.Write($buffer,0,$read)
			# New read
			$read = $responseStream.Read($buffer,0,$buffer.length)
			# Recalculate the total downloaded bytes
			$downloadedBytes = $downloadedBytes + $read
			# Calculate percent complete
			$percentComplete = (($downloadedBytes/$response.ContentLength))*100
			# Write progress bar
			Write-Progress  -Activity "Downloading '$(Split-Path -Leaf $url)' from $($server)" -Status "Downloaded $($downloadedBytes) of $($response.ContentLength) bytes." -PercentComplete $percentComplete
		}
		Write-Progress  -Activity "Finished downloading file '$(Split-Path -Leaf $url)'" -Completed
		Write-Verbose 'Finished downloading file'

		# Let's clean up
		$targetStream.Flush()
		$targetStream.Close()
		$targetStream.Dispose()
		$responseStream.Close()
		$responseStream.Dispose()
		Write-Verbose 'Finished closing connections'
	}
	catch{
		# Catching any exceptions
		Write-Warning $_.Exception.Message
	}
}