NAME

       AWS::Signature4 - Create a version4 signature for Amazon Web Services

SYNOPSIS

        use AWS::Signature4;
        use HTTP::Request::Common;
        use LWP;

        my $signer = AWS::Signature4->new(-access_key => 'AKIDEXAMPLE',
                                          -secret_key => 'wJalrXUtnFEMI/K7MDENG+bPxRfiCYEXAMPLEKEY');
        my $ua     = LWP::UserAgent->new();

        # Example POST request
        my $request = POST('https://iam.amazonaws.com',
                           [Action=>'ListUsers',
                            Version=>'2010-05-08']);
        $signer->sign($request);
        my $response = $ua->request($request);

        # Example GET request
        my $uri     = URI->new('https://iam.amazonaws.com');
        $uri->query_form(Action=>'ListUsers',
                         Version=>'2010-05-08');

        my $url = $signer->signed_url($uri); # This gives a signed URL that can be fetched by a browser
        my $response = $ua->get($url);

DESCRIPTION

       This module implement's Amazon Web Service's Signature version 4
       (http://docs.aws.amazon.com/general/latest/gr/signature-version-4.html).

METHODS

       $signer = AWS::Signature4->new(-access_key => $account_id,-secret_key => $private_key);
           Create a signing object using your AWS account ID and secret key. You may also use the
           temporary security tokens received from Amazon's STS service, either by passing the
           access and secret keys derived from the token, or by passing a
           VM::EC2::Security::Token produced by the VM::EC2 module.

           Arguments:

            Argument name       Argument Value
            -------------       --------------
            -access_key         An AWS access key (account ID)

            -secret_key         An AWS secret key

            -security_token     A VM::EC2::Security::Token object

           If a security token is provided, it overrides any values given for -access_key or
           -secret_key.

           If the environment variables EC2_ACCESS_KEY and/or EC2_SECRET_KEY are set, their
           contents are used as defaults for -access_key and -secret_key.

       $signer->sign($request [,$region] [,$payload_sha256_hex])
           Given an HTTP::Request object, add the headers required by AWS and then sign it with a
           version 4 signature by adding an "Authorization" header.

           The request must include a URL from which the AWS endpoint and service can be derived,
           such as "ec2.us-east-1.amazonaws.com." In some cases (e.g. S3 bucket operations) the
           endpoint does not indicate the region. In this case, the region can be forced by
           passing a defined value for $region. The current date and time will be added to the
           request using an "X-Amz-Date header." To force the date and time to a fixed value,
           include the "Date" header in the request.

           The request content, or "payload" is retrieved from the HTTP::Request object by
           calling its content() method.. Under some circumstances the payload is not included
           directly in the request, but is in an external file that will be uploaded as the
           request is executed. In this case, you must pass a second argument containing the
           results of running sha256_hex() (from the Digest::SHA module) on the content.

           The method returns a true value if successful. On errors, it will throw an exception.

       $url = $signer->signed_url($request)
           This method will generate a signed GET URL for the request. The URL will include
           everything needed to perform the request.

       my $url $signer->signed_url($request_or_uri [,$expires])
           Pass an HTTP::Request, a URI object, or just a plain URL string containing the proper
           endpoint and parameters needed for an AWS REST API Call. This method will return an
           appropriately signed request as a URI object, which can be shared with non-AWS users
           for the purpose of, e.g., accessing an object in a private S3 bucket.

           Pass an optional $expires argument to indicate that the URL will only be valid for a
           finite period of time. The value of the argument is in seconds.

       $signing_key =
       AWS::Signature4->signing_key($secret_access_key,$service_name,$region,$date)
           Return just the signing key in the event you wish to roll your own signature.

SEE ALSO

       VM::EC2

AUTHOR

       Lincoln Stein <lincoln.stein@gmail.com>.

       Copyright (c) 2014 Ontario Institute for Cancer Research

       This package and its accompanying libraries is free software; you can redistribute it
       and/or modify it under the terms of the GPL (either version 1, or at your option, any
       later version) or the Artistic License 2.0.  Refer to LICENSE for the full license text.
       In addition, please see DISCLAIMER.txt for disclaimers of warranty.