Reverse-proxy to external host

I would like to forward every request to the host 'sentry.example.com' with authentication to a external URL, without using redirection. The service is not directly available in my cluster and can only be reached externally. Is this possible to Traefik v2.0? If so how can I configure this using docker and on which service do I have to configure the routes?

Example:

sentry[dot]example[dot]com --> https://xxxxxx@sentry[dot]io/xxxxxx
sentry[dot]example[dot]com/test?q=1 --> xxxxxx@sentry[dot]io/xxxxxx/test?q=1

create a service using socat and apply the AddHeaders middleware to add the Authorization header.

  foo:
    image: alpine/socat
    command: tcp-listen:8080,fork,reuseaddr tcp:sentry.example.com8080
    deploy:
      labels:
         ...