# NAME

Mojo::UserAgent::Role::Resume - Role for Mojo::UserAgent that provides resuming capability during downloads

# SYNOPSIS

    use Mojo::UserAgent;

    my $class = Mojo::UserAgent->with_roles('+Resume');

    my $ua = $class->new(max_attempts => 5);

    # blocking:
    my $tx = $ua->get('http://ipv4.download.thinkbroadband.com/100MB.zip');

    # ...or non-blocking:
    $ua->get('http://ipv4.download.thinkbroadband.com/100MB.zip', sub ($ua, $tx) {
        $tx->res->content->asset->move_to('downloaded_file.zip');
        print $tx->res->headers->to_string;
    });

    # The last snippet will save the entire file to downloaded_file.zip, and will print:
    Connection: keep-alive
    Content-Length: 103124119
    Server: nginx
    ETag: "48401320-6400000"
    Last-Modified: Fri, 30 May 2008 14:45:52 GMT
    Date: Thu, 27 Aug 2020 16:25:18 GMT
    Content-Range: bytes 1733481-104857599/104857600
    Content-Type: application/zip
    Access-Control-Allow-Origin: *

# DESCRIPTION

Mojo::UserAgent::Role::Resume is a role for Mojo::UserAgent that allows the user-agent to
retry a URL upon failure.

Retries are made after a connection error or after a server error (HTTP error 5xx) occurs.

It will intelligently determine whether the server it's downloading from properly supports ranged requests,
and if it doesn't, upon failure it will stop asking for a resume and request the complete file again.

It will request the original user-provided URL in its next attempts, not the one that may result from
redirections.

The $tx object returned is the last HTTP transaction that took place.

# ATTRIBUTES

[Mojo::UserAgent::Role::Resume](https://metacpan.org/pod/Mojo%3A%3AUserAgent%3A%3ARole%3A%3AResume) adds the following attribute to the [Mojo::UserAgent](https://metacpan.org/pod/Mojo%3A%3AUserAgent) object:

## max\_attempts

    my $ua = $class->new;
    $ua->max_attempts(5);

The number of attempts it will try (at most). What matters for each download is the value this attribute holds
at the time the first attempt takes place.

# TODO

- Write tests
- Check whether the module should also check whether "content received < total\_size\_based\_on\_headers" when
determining whether to retry
- Add events
- Find the right minimum versions of its dependencies

Despite the above, this module works.

# LICENSE

Copyright (C) Karelcom OÜ.

This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.

# AUTHOR

KARJALA Corp <karjala@cpan.org>