Add Unshorten plugin to follow redirects from known short URLs. Curre…

…ntly only knows t.co.

lib/Text/AutoLink/Plugin/Unshorten.pm

@@ -0,0 +1,40 @@
+package Text::AutoLink::Plugin::Unshorten;
+use strict;
+use warnings;
+use base qw(Text::AutoLink::Plugin);
+
+use LWP::UserAgent ();
+my $ua = LWP::UserAgent->new;
+
+sub process
+{
+    my $self = shift;
+    my $ref  = shift;
+
+    $$ref =~ s/https?:\/\/t\.co\/([a-z0-9]+)/
+        $self->unshorten($$ref)
+    /gex;
+}
+
+sub unshorten
+{
+    my $self = shift;
+    my $url  = shift;
+
+    my $request = HTTP::Request->new(HEAD => $url);
+    my $response = $ua->request($request);
+
+    if ($response->redirects) {
+        return $response->request->uri;
+    }
+
+    return $url;
+}
+
+1;
+
+=head1 NAME
+
+Text::AutoLink::Plugin::Unshorten - Follow redirects to unshorten
+
+=cut