my $our_etag = Mojo::ByteStream->new($body . $VERSION)->md5_sum;
$self->res->headers->header('ETag' => $our_etag);
my $browser_etag = $self->req->headers->header('If-None-Match');
return unless $browser_etag && $browser_etag eq $our_etag;
my $our_etag = Mojo::ByteStream->new($body . $VERSION)->md5_sum;
$self->res->headers->header('ETag' => $our_etag);
my $browser_etag = $self->req->headers->header('If-None-Match');
return unless $browser_etag && $browser_etag eq $our_etag;