Perl

REST Stream Response to File (Streaming Download) (Amazon S3)

See more Amazon S3 (new) Examples

Demonstrates how to stream the response body directly to a file. (The example shows how to stream a JPG from the Amazon S3 service.) Chilkat2 Perl

use strict;
use warnings;
use Chilkat2;

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

my $rest = Chilkat2::Rest->new;

# Connect to the Amazon AWS REST server.
my $bTls = 1;
my $port = 443;
my $bAutoReconnect = 1;
my $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.
my $authAws = Chilkat2::AuthAws->new;
$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) {
    print $rest->LastErrorText, "\n";
    exit;
}

# Read the response header.
my $responseStatusCode = $rest->ReadResponseHeader();
if ($responseStatusCode < 0) {
    print $rest->LastErrorText, "\n";
    exit;
}

print 'Response status code = ', $responseStatusCode, "\n";

# 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 == 200) {
    my $bodyStream = Chilkat2::Stream->new;

    # The stream's sink will be a file.
    $bodyStream->SinkFile('qa_output/starfish.jpg');

    # Read the response body to the stream.  Given that we've
    # set the stream's sink to a file, it will stream directly
    # to the file.
    $success = $rest->ReadRespBodyStream($bodyStream, 1);
    if (!$success) {
        print $rest->LastErrorText, "\n";
        exit;
    }

    print "Successfully received the JPG file.\n";
} else {
    my $errResponse = $rest->ReadRespBodyString();
    if (!$rest->LastMethodSuccess) {
        print $rest->LastErrorText, "\n";
    } else {
        print $errResponse, "\n";
    }
}