use strict;
use warnings;
use Mojo::UserAgent;

my $url =
'https://public-api.wordpress.com/rest/v1/read/feed/?url=the-art-of-autism.com';

my $ua = Mojo::UserAgent->new;

my $feedurl = $ua->get( $url )->result->json->{'feeds.meta.links.feed'};
print $feedurl;