service behind HTTPS will not return short url with HTTPS

[posativ]

~> curl -X POST https://krz.us/api/v1/short \
    -d '{"url": "http://google.de/", "key": null}' \
    -H "Content-Type: application/json"
{"wish": null, "url_long": "http://google.de/", "url_short": "http://krz.us/3iJ"}

[izzy]

I guess the server/proxy is missing a header to tell the server it's run over HTTPS. I'm not sure if Flask will autodetect the header then. Will test that later™