gistfile1.pl

#!/usr/bin/env perl

use AnyEvent;
use AnyEvent::Redis;
use Plack::Request;
use v5.12;

my $redis = AnyEvent::Redis->new;

sub {
  my $req = Plack::Request->new(shift);
  my $params = $req->parameters;
  my ($key) = $req->path =~ /^\/(.+)/;

  if (!defined $key) {
    return [404, [], ["not found"]];
  }

  return sub {
    my $res = shift;
    given ($req->method) {
      when ("GET") {
        $redis->get($key, sub {
          my $value = shift;
          if ($value) {
            $res->([200, [], [$value]]);
          }
          else {
            $res->([404, [], ["not found"]]);
          }
        });
      }
      when ("PUT") {
        my $value = $params->{value};
        $redis->set($key, $value, sub {
          $res->([200, [], [$value]]);
        });
      }
      default {
        $res->([405, [], ["method not allowed"]]);
      }
    }
  };
};