Sample Perl Code Using DreamObjects S3-compatible API

This article lists several Perl code examples to interact with DreamObjects.

Creating a Connection

Create a connection so you can interact with the server.

use Amazon::S3;
my $access_key = 'put your access key here!';
my $secret_key = 'put your secret key here!';

my $conn = Amazon::S3->new({
        aws_access_key_id     => $access_key,
        aws_secret_access_key => $secret_key,
        host                  => '',
        secure                => 1,
        retry                 => 1,

Listing Owned Buckets

Get a list of Amazon::S3::Bucket objects you own and print out the bucket name and creation date of each bucket.

my @buckets = @{$conn->buckets->{buckets} || []};
foreach my $bucket (@buckets) {
        print $bucket->bucket . "\t" . $bucket->creation_date . "\n";

The output will look something like this:

mahbuckat1   2011-04-21T18:05:39.000Z
mahbuckat2   2011-04-21T18:05:48.000Z
mahbuckat3   2011-04-21T18:07:18.000Z

Creating a Bucket

Create a new bucket called my-new-bucket.

my $bucket = $conn->add_bucket({ bucket => 'my-new-bucket' });

Listing a Bucket’s Content

Get a list of hashes with info about each object in the bucket and print out each object’s name, the file size, and last modified date.

my @keys = @{$bucket->list_all->{keys} || []};
foreach my $key (@keys) {
        print "$key->{key}\t$key->{size}\t$key->{last_modified}\n";

The output will look something like this:

myphoto1.jpg 251262  2011-08-08T21:35:48.000Z
myphoto2.jpg 262518  2011-08-08T21:38:01.000Z

Deleting a Bucket

The Bucket must be empty, otherwise it won’t work.


Forced Delete for Non-empty Buckets

not available in the Amazon::S3 perl module

Creating an Object

Create a file hello.txt with the string "Hello World!"

        'hello.txt', 'Hello World!',
        { content_type => 'text/plain' },

Change an Object’s ACL

Make the object hello.txt publicly readable and secret_plans.txt to be private.

        key       => 'hello.txt',
        acl_short => 'public-read',
        key       => 'secret_plans.txt',
        acl_short => 'private',

Download an Object (to a file)

Download the object perl_poetry.pdf and save it in /home/larry/documents/.

$bucket->get_key_filename('perl_poetry.pdf', undef,

Delete an Object

Delete the object goodbye.txt.


Generate Object Download URLs (signed and unsigned)

This generates an unsigned download URL for hello.txt. This works because hello.txt was made public by setting the ACL above. Then this generates a signed download URL for secret_plans.txt that will work for 1 hour. Signed download URLs will work for the time period even if the object is private (when the time period is up, the URL will stop working).

The Amazon::S3 module does not have a way to generate download URLs, so these examples use another module instead. Unfortunately, most modules for generating these URLs assume that you are using Amazon. For this reason, a more obscure module, Muck::FS::S3 is used. This should be the same as Amazon’s sample S3 perl module, but this sample module is not in CPAN. So, you can either use CPAN to install Muck::FS::S3, or install Amazon’s sample S3 module manually. If you go the manual route, you can remove Muck::FS:: from the example below.

use Muck::FS::S3::QueryStringAuthGenerator;
my $generator = Muck::FS::S3::QueryStringAuthGenerator->new(
        0, # 0 means use 'http'. set this to 1 for 'https'

my $hello_url = $generator->make_bare_url($bucket->bucket, 'hello.txt');
print $hello_url . "\n";

$generator->expires_in(3600); # 1 hour = 3600 seconds
my $plans_url = $generator->get($bucket->bucket, 'secret_plans.txt');
print $plans_url . "\n";

The output will look something like this:

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Article last updated .