Attempt to rewrite minimal Traefik example to use TLS does not work - docker-compose

Question

The minimal example from https://doc.traefik.io/traefik/user-guides/docker-compose/basic-example/ works on my local machine. However, when I try to adapt this to use TLS I run into an issue. I'm a Traefik newbie, so I might be doing a stupid mistake.
This is my attempt:
version: "3.3"
services:
traefik:
image: "traefik:v2.8"
container_name: "traefik"
command:
- "--log.level=DEBUG"
- "--accesslog=true"
- "--api.insecure=true"
- "--providers.docker=true"
- "--providers.docker.exposedbydefault=false"
- "--entrypoints.web.address=:80"
- "--entrypoints.websecure.address=:443"
ports:
- "443:443"
- "8080:8080"
volumes:
- "/var/run/docker.sock:/var/run/docker.sock:ro"
whoami:
image: "traefik/whoami"
container_name: "simple-service"
labels:
- "traefik.enable=true"
- "traefik.http.routers.whoami.rule=Host(`127.0.0.1`)"
- "traefik.http.routers.whoami.entrypoints=websecure"
So the major modification is to use "traefik.http.routers.whoami.entrypoints=websecure" instead of "traefik.http.routers.whoami.entrypoints=web"
Running
$ curl -k https://127.0.0.1
I get
404 page not found
The traefik log shows no routing related issues and the internal traefik setup for routing etc shown using curl https://127.0.0.1:8080/api/rawdata | jq . looks the same as the one of the working example, except the changed port.

Answer 1

So I opted for new answer instead of just editing the old answer. (Reason being even incorrect answers teach something).
My reference is this great post by Marc Mogdanz (link: https://marcmogdanz.de/posts/infrastructure-with-traefik-and-cloudflare/).
The direct answer to your query is:
Expose port 8080 but do not publish it
Add a host name rule. This will allow Traefik to route a URL request to its own port 8080.
The affected part of the compose file would be as follows (assuming that the URL https://dashboard.example.com is the desired URL to reach the dashboard):
expose:
- 8080
...
labels:
- "traefik.enable=true"
- "traefik.http.routers.traefik.rule=Host(`dashboard.example.com`)"
- "traefik.http.routers.traefik.tls=true"
- "traefik.http.services.traefik.loadbalancer.server.port=8080"
Finally, I noticed you are testing on localhost. If you are testing on a local machine, use localhost for the dashboard and keep 127.0.0.1 for whoami.
Or, alternately, add a static entry for a subdomain (see https://stackoverflow.com/a/19016600).
Either way, Traefik is looking at the SNI requested - not necessarily the IP address - when matching the Host rule.
Request ----> Docker:443 ---> {Traefik}-"SNI?"---"127.0.0.1"---> {whoami}
| \
| \
8080<---"dashboard.localhost"

Answer 2

Add the following entry to your Traefik:
"--entrypoints.websecure.address=:8080"
Normally it would be 8080 for http and 8443 for https alternative ports, but since your example specifically states https://~:8080, I have adapted it accordingly.