PowerShell

REST Read Response with Stream API

See more REST Examples

Demonstrates how to make a REST call that returns a binary body, and to receive the body through a stream API. PowerShell

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

$success = $false

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

$rest = New-Object Chilkat.Rest

# Connect to the Amazon AWS REST server.
$bTls = $true
$port = 443
$bAutoReconnect = $true
$success = $rest.Connect("s3.amazonaws.com",$port,$bTls,$bAutoReconnect)

# ----------------------------------------------------------------------------
# Important: For buckets created in regions outside us-east-1,
# there are three important changes that need to be made.
# See Working with S3 Buckets in Non-us-east-1 Regions for the details.
# ----------------------------------------------------------------------------

# Provide AWS credentials for the REST call.
$authAws = New-Object Chilkat.AuthAws
$authAws.AccessKey = "AWS_ACCESS_KEY"
$authAws.SecretKey = "AWS_SECRET_KEY"
$authAws.ServiceName = "s3"
$success = $rest.SetAuthAws($authAws)

# Set the bucket name via the HOST header.
# In this case, the bucket name is "chilkat100".
$rest.Host = "chilkat100.s3.amazonaws.com"

# Send the request to download the JPG.
$success = $rest.SendReqNoBody("GET","/starfish.jpg")
if ($success -ne $true) {
    $($rest.LastErrorText)
    exit
}

# Read the response header.
$responseStatusCode = $rest.ReadResponseHeader()
if ($responseStatusCode -lt 0) {
    $($rest.LastErrorText)
    exit
}

$("Response status code = " + $responseStatusCode)

# We expect a 200 response status if the JPG data is coming.
# Otherwise, we'll get a string response body with an error message(or no response body).
if ($responseStatusCode -ne 200) {
    $errResponse = $rest.ReadRespBodyString()
    if ($rest.LastMethodSuccess -ne $true) {
        $($rest.LastErrorText)
    }
    else {
        $($errResponse)
    }

    exit
}

$bodyStream = New-Object Chilkat.Stream
# Set a 10 second read timeout for the stream. 
# (Give up if no data arrives within 10 seconds after calling a read method.)
$bodyStream.ReadTimeoutMs = 10000

# Create a background thread task to read the response body (which feeds
# it to the bodyStream object.)
$readResponseBodyTask = $rest.ReadRespBodyStreamAsync($bodyStream,$true)

# Start the task. 
$success = $readResponseBodyTask.Run()

# The application can now read the bodyStream...
while (($bodyStream.EndOfStream -ne $true)) {

    # Read the next chunk of bytes (whatever is immediately available,
    # or wait for more data (up to 10 seconds because we set the stream's ReadTimeoutMs property)
    $nextChunk = $bodyStream.ReadBytes()
    if ($bodyStream.LastMethodSuccess -ne $true) {
        $("Failed to receive more response data.")
        # Make sure the background task is aborted/cancelled.
        $success = $readResponseBodyTask.Cancel()

        exit
    }

    # OK.. the app has the next chunk of the body, and may do whatever it wishes with it...
}

$("Successfully received the entire response body.")