(PowerShell) REST Download Bandwidth Throttle

Demonstrates how to use download bandwidth throttling with the REST API. This example will download a file from Drobox using a file stream, with a limit on the bandwidth that can be used for the transfer.

Chilkat .NET Downloads Chilkat .NET Assemblies

Add-Type -Path "C:\chilkat\ChilkatDotNet47-9.5.0-x64\ChilkatDotNet47.dll"

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

# A Dropbox access token should have been previously obtained.
# Dropbox access tokens do not expire.
# See Dropbox Access Token.

# To use bandwidth throttling, the connection should be made using the socket API.
# This provides numerous properties to customize the connection, such as
# BandwidthThrottleDown, BandwidthThrottleUp, ClientIpAddress, ClintPort, Http Proxy,
# KeepAlive, PreferIpv6, RequireSslCertVerify, SoRcvBuf, SoSndBuf, SoReuseAddr,
# SOCKS proxy, TcpNoSDelay, TlsPinSet, TlsCipherSuite, SslAllowedCiphers, etc.

$socket = New-Object Chilkat.Socket
$maxWaitMs = 5000
$success = $socket.Connect("content.dropboxapi.com",443,$true,$maxWaitMs)
if ($success -ne $true) {
    $($socket.LastErrorText)
    $("Connect Fail Reason: " + $socket.ConnectFailReason)
    exit
}

# Set the download bandwidth throttle rate to 50000 bytes per second.
$socket.BandwidthThrottleDown = 50000

$rest = New-Object Chilkat.Rest

# Tell the REST object to use the connected socket.
$rest.UseConnection($socket,$true)

# The remainder of this example is identical to the example at:
# Dropbox Download File.

# Add request headers.
$rest.AddHeader("Authorization","Bearer DROPBOX_ACCESS_TOKEN")

# The download "parameters" are contained in JSON passed in an HTTP request header.
# This is the JSON indicating the file to be downloaded:
# { 
#    "path": "/Homework/lit/hamlet.xml",
# }

$json = New-Object Chilkat.JsonObject
$json.AppendString("path","/Homework/lit/hamlet.xml")
$rest.AddHeader("Dropbox-API-Arg",$json.Emit())

# Setup a file stream for the download
$fileStream = New-Object Chilkat.Stream
$fileStream.SinkFile = "qa_output/hamletFromDropbox.xml"

# Indicate that the call to FullRequestNoBody should send the response body
# to fileStream if the response status code is 200.
# If a non-success response status code is received, then nothing
# is streamed to the output file and the error response is returned by FullRequestNoBody.
$expectedStatus = 200
$rest.SetResponseBodyStream($expectedStatus,$true,$fileStream)

$responseStr = $rest.FullRequestNoBody("POST","/2/files/download")
if ($rest.LastMethodSuccess -ne $true) {
    $($rest.LastErrorText)
    exit
}

# When successful, Dropbox responds with a 200 response code.
if ($rest.ResponseStatusCode -ne 200) {
    # Examine the request/response to see what happened.
    $("response status code = " + $rest.ResponseStatusCode)
    $("response status text = " + $rest.ResponseStatusText)
    $("response header: " + $rest.ResponseHeader)
    $("response body (if any): " + $responseStr)
    $("---")
    $("LastRequestStartLine: " + $rest.LastRequestStartLine)
    $("LastRequestHeader: " + $rest.LastRequestHeader)
    exit
}

# Information about the downloaded file is also available as JSON in a response header.
# The "dropbox-api-result" response header contains the information.  For example:
$apiResult = $rest.ResponseHdrByName("dropbox-api-result")
$($apiResult)

# In this case, the pretty-formatted dropbox-api-result JSON looks like this:
# { 
#   "name": "hamlet.xml",
#   "path_lower": "/homework/lit/hamlet.xml",
#   "path_display": "/Homework/lit/hamlet.xml",
#   "id": "id:74FkdeNuyKAAAAAAAAAAAQ",
#   "client_modified": "2016-06-02T23:19:00Z",
#   "server_modified": "2016-06-02T23:19:00Z",
#   "rev": "9482db15f",
#   "size": 279658
# }

# Load the JSON, pretty-print it, and demonstrate how to get some values...
$jsonResult = New-Object Chilkat.JsonObject
$jsonResult.EmitCompact = $false
$jsonResult.Load($apiResult)
# Show the JSON pretty-printed...
$($jsonResult.Emit())

# Sample code to get data from the JSON response:
$size = $jsonResult.IntOf("size")
$("size = " + $size)

$rev = $jsonResult.StringOf("rev")
$("rev = " + $rev)

$clientModified = $jsonResult.StringOf("client_modified")
$ckdt = New-Object Chilkat.CkDateTime
$ckdt.SetFromTimestamp($clientModified)
$bLocalTime = $true
$dt = $ckdt.GetDtObj($bLocalTime)
$([string]$dt.Day + "/" + $dt.Month + "/" + $dt.Year + " " + $dt.Hour + ":" + $dt.Minute)