my @methods = qw/ get post response /; # Used by Env/GlipGlop.

package Env {
    use Moo;
    has "method" =>
        is => "rwp",
        isa => sub {
            grep $_ eq $_[0], @methods
                or die "No such method: $_[0]";
        };
};

package GlipGlop {
    use Moo;
    use Scalar::Util "blessed";

    has agent =>
        is => "lazy",
        handles => \@methods,
        isa => sub {
            @methods == grep $_[0]->can($_), @methods
                or die "ua must be able to ", join ", ", @methods;
        };

    sub _build_agent {
        require WWW::Mechanize;
        WWW::Mechanize->new( autocheck => 0 );
    }

    has env =>
        is => "rwp",
        isa => sub { blessed $_[0] eq "Env" },
        handles => [ "method" ],
        default => sub {
            no warnings "uninitialized";
            Env->new({ method => lc $ENV{REQUEST_METHOD} || "get" });
        };

    sub do_something_with_a_uri {
        my $self = shift;
        my $uri = shift || die "uri is required";
        my $method = $self->method; # "env" handles this.
        # You have to work out how to keep the JSON/Env stuff.
        $self->$method($uri); # the "ua" handles the @methods.
    }
};

use strictures;

my $gg = GlipGlop->new;
my $uri = shift || "http://example.org";
my $response = $gg->do_something_with_a_uri($uri);
my ( $title ) = $response->content =~ m{<title[^>]*>([^<]+)}i;
print $title, $/;

__END__
moo@cow~>perl pm-1142751
Example Domain
moo@cow~>perl pm-1142751 "http://perlmonks.org/?node_id=1142751"
Better syntax for dynamic method on internal object ?