Redirect not working when behind load balancer

[Rhadros]

If Kong is behind a load balancer a check for https is not working because it's always off. You should additionally check for the header value in X-Forwarded-Proto. If not "https" then you should redirect.
This should work behind a load balancer (at least it works on Heroku):

function HttpFilterHandler:access(conf)
  HttpFilterHandler.super.access(self)

  if ngx.var.https ~= "on" and ngx.var.http_x_forwarded_proto ~= "https" then
    return ngx.redirect("https://" .. ngx.var.host .. ngx.var.request_uri, ngx.HTTP_MOVED_PERMANENTLY)
  end
end

[dsteinkopf]

see PR #5 . This also is fixed in my repo dsteinkopf#1 (please use branch repo-dsteinkopf -> https://github.com/dsteinkopf/kong-http-to-https-redirect/tree/repo-dsteinkopf)

[Rhadros]

Sorry for the long delay, but looks the same like my solution. I will close this one, because #5 has more features included