Port forwarding problem using Traefik and docker-compose - docker-compose

Question

I want the next port forwarding:
http://traefik.service.localhost/ -> Traefik UI
http://api.service.localhost/ -> 'Hello-Word' page from api-service
Here is my attempt to create appropriate docker-compose.yml file:
version: '3.8'
services:
reverse-proxy:
image: traefik:v2.4
container_name: reverse-proxy
command:
- "--api.insecure=true"
- "--providers.docker"
ports:
- "80:80"
- "8080:8080"
labels:
- traefik.enable=true
- traefik.docker.network=pred-network
volumes:
- /var/run/docker.sock:/var/run/docker.sock
networks:
- pred-network
api-service:
image: x86_64/prediction-service:0.8.1
container_name: api-service
environment:
SERVING_SERVICE: model-service
expose:
- 80
labels:
- traefik.enable=true
- traefik.http.routers.api-service.rule=Host(`api.service.localhost`)
networks:
- pred-network
networks:
pred-network:
I am getting the following:
http://traefik.service.localhost/ -> HTTP Error 404. The requested resource is not found.
http://api.service.localhost/ -> HTTP Error 404. The requested resource is not found.
The only link that actually works:
http://api.service.localhost:8080/ -> Traefik UI
If I would include:
ports:
- "8070:80"
into api-service part of docker-compose.yml I could access my 'Hello-Word':
http://localhost:8070/ -> "Hello-Word"
In this case it not get routed through Traefik but directly through api-service. Is it possible to do it over Traefik?

Answer 1

To have a service routed by traefik with docker, you should have labels. Traefik will fetch those labels in order to know how to do routing.
Thus, to have request of api.service.localhost routed to your api service, you should have the label that define the corresponding rule:
traefik.http.routers.service.rule=Host(`api.service.localhost`)
As for the label of Traefik, you should have two labels:
traefik.http.routers.traefik.rule=Host(`traefik.service.localhost`)
traefik.http.routers.traefik.service=api#internal
Beside those traefik labels, you should tell traefik to expose the dashboard using a specific service by adding this configuration: --api.dashboard (More help to expose the dashboard here).
Note, if your api service uses another port than the one by default, you could add this label:
traefik.http.services.service.loadbalancer.server.port=80
Ps, do not expose twice the port 80, you only need to expose it for the traefik container.