Traefik: How to configure route to direct every request to http service? - traefik

Question

I'm too dumb and Google is not helpful.
I'm trying to set up the simplest configuration:
Traefik 2 (in latest Docker container), handling incoming requests...
should direct all incoming requests (http, https) to another service, the Traefik whoami demo container (which I've got already running)...
while terminating the SSL connection, calling the service via http on port 80...
while using a configuration file with explicitly defined routes
How would I configure this? Here's my try:
entryPoints:
web:
address: :80
websecure:
address: :443
log:
filePath: "/home/LogFiles/traefik.log"
level: DEBUG
accessLog:
filePath: "/home/LogFiles/trafik-access.log"
providers:
file:
filename: "/home/traefik.yml"
http:
routers:
route-https:
rule: "Host(`traefik-test.azurewebsites.net`) && PathPrefix(`/whoami`)"
service: "whoami"
tls: {}
route-http:
rule: "Host(`traefik-test.azurewebsites.net`) && PathPrefix(`/whoami`)"
service: "whoami"
services:
whoami:
loadBalancer:
servers:
- url: "http://whoami-test.azurewebsites.net/"
I am not sure about how the https to http conversion works. The documentation says that it's happening automatically. Another part of the doc says you have to use two routers and the tls: {} part tells to terminate the TLS connection. That's what I am doing above. (Is that correct?)
The whomami service URL can be accessed in the browser without problems, via http and https. But when calling it via Traefik (for the above sample this would be https://traefik-test.azurewebsites.net/whoami) I get a 400 and the Browser shows "Bad Request". I suspect the https->http part is not working.
Samples on the web commonly show how to orchestrate multiple containers that get discovered by Traefik. That's not what I'm doing here. I just want to tell Treafik about my already running service. Take every request, route everything to my service via http. Should be simple?
Any hints are appreciated.

Answer 1

There were two errors preventing my configuration from working.
Number one: nasty YAML. See the two spaces before "-"?
servers:
- url: "http://whoami-test.azurewebsites.net/"
They have to go for this to be valid:
servers:
- url: "http://whoami-test.azurewebsites.net/"
Number two: the Host header set by Traefik (which is set to the proxy host) makes the service web app redirect back to my proxy. The passHostHeader: false configuration was necessary:
services:
whoami:
loadBalancer:
passHostHeader: false # <------ added this
servers:
- url: "http://whoami-test.azurewebsites.net/"
Passing the proxy host as "Host" header causes some services to 301-redirect back to the proxy, causing a redirect loop between proxy and service. A .NET Core app (Kestrel) will respond with "Bad Request" instead. Omitting the header is the solution in my case.