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It is not a replacement for [Amazon::S3](https://metacpan.org/pod/Amazon%3A%3AS3) or [Net::Amazon::S3](https://metacpan.org/pod/Net%3A%3AAmazon%3A%3AS3), which
support the full S3 API surface including multipart upload, bucket
management, ACLs, versioning, and presigned URLs. If you need those
features, use one of those distributions instead.

[Amazon::S3::Thin](https://metacpan.org/pod/Amazon%3A%3AS3%3A%3AThin) is another excellent lightweight S3 client with a
similar philosophy and a longer track record. It is more complete than
this module - supporting presigned URLs, bulk delete, and
virtual-hosted-style requests - and returns raw [HTTP::Response](https://metacpan.org/pod/HTTP%3A%3AResponse)
objects so callers handle status codes and errors
themselves. `Amazon::S3::Lite` differs in three ways: it has no
dependency on LWP (`Amazon::S3::Thin` defaults to [LWP::UserAgent](https://metacpan.org/pod/LWP%3A%3AUserAgent)),
it returns parsed hashrefs rather than raw response objects, and it
has first-class support for Lambda IAM role credential rotation. If
you need the broader feature set or prefer direct HTTP access,
`Amazon::S3::Thin` is a fine choice.

# CONSTRUCTOR

## new

    my $s3 = Amazon::S3::Lite->new(\%options);

Returns a new `Amazon::S3::Lite` object. Options:

- region (options, default: us-east-1)

    The AWS region for your bucket, e.g. `us-east-1`.

- aws\_access\_key\_id / aws\_secret\_access\_key

    Static credentials. `token` may also be supplied for STS temporary
    credentials (as used by Lambda execution roles).

    These are only consulted if no `credentials` object is provided.

- token

    Optional STS session token, used alongside static credentials for
    temporary credential sets.

- credentials

    An object providing credential getters. The object must respond to:

        $creds->aws_access_key_id
        $creds->aws_secret_access_key
        $creds->token            # may return undef

    Any object that satisfies this interface is accepted -
    [Amazon::Credentials](https://metacpan.org/pod/Amazon%3A%3ACredentials), [Paws::Credential::\*](https://metacpan.org/pod/Paws%3A%3ACredential%3A%3A%2A), or your own. The
    getters are called at request time, so objects that refresh expiring
    credentials transparently are supported.

- logger

    An object providing the standard log methods:

        $logger->trace(...)
        $logger->debug(...)
        $logger->info(...)
        $logger->warn(...)
        $logger->error(...)

    If not supplied, the module looks for [Log::Log4perl](https://metacpan.org/pod/Log%3A%3ALog4perl). If available,
    it calls `Log::Log4perl::easy_init` with the configure log level (or
    WARN) and logs to STDERR.  If Log::Log4perl is not installed, a
    minimal internal logger.

- host

    Override the S3 endpoint host. Defaults to `s3.amazonaws.com`.
    Useful for S3-compatible services (MinIO, Ceph, LocalStack).

- secure

    Use HTTPS. Default is 1 (true). Set to 0 only for testing against
    local S3-compatible endpoints.

- timeout

    HTTP request timeout in seconds. Default is 30.

## Credential resolution order

When no `credentials` object is passed, credentials are resolved in
this order:

1. Constructor arguments `aws_access_key_id` and `aws_secret_access_key`.
2. Environment variables `AWS_ACCESS_KEY_ID`, `AWS_SECRET_ACCESS_KEY`,
and optionally `AWS_SESSION_TOKEN`.
3. [Amazon::Credentials](https://metacpan.org/pod/Amazon%3A%3ACredentials), if installed. This covers IAM instance roles,
Lambda execution roles, ECS task roles, and `~/.aws/credentials`
profiles.
4. If none of the above yield credentials, the constructor croaks.

# METHODS

All methods croak on unrecoverable errors (network failure, HTTP 5xx).
HTTP 404 is not an exception - methods that can meaningfully return
`undef` for a missing resource do so.

## list\_objects\_v2

    my $result = $s3->list_objects_v2($bucket, %options);

Lists objects in `$bucket` using the S3 ListObjectsV2 API.

Options:

- prefix

    Limit results to keys beginning with this string.

- delimiter

    Group keys sharing a common prefix up to this delimiter. Grouped
    prefixes are returned in `common_prefixes`.

- max\_keys

share/README.md  view on Meta::CPAN

- start\_after

    Return only keys lexicographically after this value.

Returns a hashref:

    {
      bucket                 => 'my-bucket',
      prefix                 => 'logs/',
      is_truncated           => 0,
      next_continuation_token => undef,        # set when is_truncated is true
      key_count              => 42,
      objects                => [
        {
          key           => 'logs/2024-01-01.gz',
          size          => 102400,
          last_modified => '2024-01-01T00:00:00.000Z',
          etag          => 'abc123',
          storage_class => 'STANDARD',
        },
        ...
      ],
      common_prefixes        => [],            # populated when delimiter is set
    }

## list\_all\_objects\_v2

    my @objects = $s3->list_all_objects_v2($bucket, %options);

Convenience wrapper around ["list\_objects\_v2"](#list_objects_v2) that automatically
follows continuation tokens and returns a flat list of all matching
object hashrefs in a single call.

Accepts the same options as `list_objects_v2` except
`continuation_token` (which is managed internally) and `delimiter`
(which is silently ignored - see below).

    my @logs = $s3->list_all_objects_v2('my-bucket', prefix => 'logs/');

    foreach my $obj (@logs) {
      printf "%s  %d bytes\n", $obj->{key}, $obj->{size};
    }

Be mindful of memory when listing buckets with large numbers of
objects.  For very large listings, use ["list\_objects\_v2"](#list_objects_v2) directly
and process each page as it arrives.

`delimiter` and `common_prefixes` are not supported by this method.
The purpose of `list_all_objects_v2` is a complete flat listing of
all matching keys. Hierarchical directory-style traversal using
`delimiter` is inherently page-by-page and should use
["list\_objects\_v2"](#list_objects_v2) directly.

Returns a (possibly empty) list of object hashrefs, each with the same
fields as the elements of `objects` in the `list_objects_v2`
response.

- log\_level

    Log level for the internal logger. Accepted values: `trace`, `debug`,
    `info`, `warn`, `error`, `fatal`. Default is `warn`. Only consulted
    when no `logger` object is supplied and Log::Log4perl is not available
    or not yet initialized.

## get\_object

    my $obj = $s3->get_object($bucket, $key);
    my $obj = $s3->get_object($bucket, $key, %options);

Fetches the object at `$key` in `$bucket`.

Returns `undef` if the key does not exist (HTTP 404).

Returns a hashref on success:

    {
      content        => '...',          # raw bytes; absent when filename is used
      content_type   => 'application/json',
      content_length => 1024,
      etag           => 'abc123',
      last_modified  => 'Tue, 01 Jan 2024 00:00:00 GMT',
      metadata       => {               # x-amz-meta-* headers, lowercased
        source => 'lambda',
      },
    }

Options:

- range

    An HTTP Range header value, e.g. `bytes=0-1023`, for partial fetches.

- filename

    Path to a local file where the object body should be written. When
    supplied, the response body is streamed directly to disk via
    HTTP::Tiny's `:content_file` mechanism and `content` is omitted from
    the returned hashref. The file is created or overwritten.

        my $meta = $s3->get_object('my-bucket', 'data/dump.csv',
          filename => '/tmp/dump.csv',
        );
        # $meta->{content} is absent; file is on disk

    This is the recommended approach for large objects in Lambda where
    holding the full body in memory is undesirable.

## head\_object

    my $meta = $s3->head_object($bucket, $key);

Fetches metadata for `$key` without retrieving the object body.
Useful for existence checks and reading `x-amz-meta-*` headers
cheaply.

Returns `undef` if the key does not exist (HTTP 404).

Returns a hashref on success with the same fields as `get_object`
except `content`, which is always absent.