How to set Traefik 2.4 service name in docker-compose labels - docker

Question

Is there any way to set traefik.http.services name in docker-compose labels?
Lets say i have simple docker-compose.yml:
version: '3.4'
services:
traefik:
image: "traefik:v2.4.2"
command:
- --log.level=warning
- --api.insecure=true
- --api.dashboard=true
- --providers.docker=true
- --providers.docker.exposedbydefault=false
- --entrypoints.web.address=:80
ports:
- "80:80"
volumes:
- "/var/run/docker.sock:/var/run/docker.sock:ro"
labels:
- traefik.enable=true
# Dashboard
- traefik.http.routers.traefik.rule=Host(`traefik.localhost`)
# this is interesting - traefik is naming his api service somehow
- traefik.http.routers.traefik.service=api#internal
- traefik.http.services.traefik.loadbalancer.server.port=8080
whoami:
image: "traefik/whoami"
labels:
- traefik.enable=true
- traefik.http.routers.webwho.rule=Host(`who.localhost`)
This works great, after docker-compose up i can see the dashboard at http://traefik.localhost and "whoami" at http://who.localhost
The problem is the name of 'whoami' traefik service - it is something like whoami-{name_of_project} which is problem when i want to reference it in other label.
For example, i want to use new 'foo' docker service as 404.html provider (in this example i will use traefik/whoami image, which is silly, but hey, this is only example ;) )
I do that by using low priority "catch all" router:
version: '3.4'
services:
traefik:
image: "traefik:v2.4.2"
command:
- --log.level=warning
- --api.insecure=true
- --api.dashboard=true
- --api.debug=true
- --providers.docker=true
- --providers.docker.exposedbydefault=false
- --entrypoints.web.address=:80
ports:
- "80:80"
volumes:
- "/var/run/docker.sock:/var/run/docker.sock:ro"
labels:
- traefik.enable=true
# Dashboard
- traefik.http.routers.traefik.rule=Host(`traefik.localhost`)
# this is interesting - traefik is naming his api service somehow
- traefik.http.routers.traefik.service=api#internal
- traefik.http.services.traefik.loadbalancer.server.port=8080
whoami:
image: "traefik/whoami"
labels:
- traefik.enable=true
- traefik.http.routers.webwho.rule=Host(`who.localhost`)
foo:
image: "traefik/whoami"
labels:
- traefik.enable=true
- traefik.http.routers.error-router.rule=HostRegexp(`{host:.+}`)
- traefik.http.routers.error-router.priority=1
- traefik.http.routers.error-router.middlewares=error-pages-middleware
- traefik.http.middlewares.error-pages-middleware.errors.status=400-599
# nope!
# actual name of this service (as seen in traefik dashboard) is something like 'foo-test'
# and this will not work.
# (btw, there is very clear Error Message in traefik console about service foo does not exists,
# making debugging pleasant experience :) Thank you Traefik!)
- traefik.http.middlewares.error-pages-middleware.errors.service=foo
- traefik.http.middlewares.error-pages-middleware.errors.query=/{status}.html
but i have no idea how to set name of traefik service so i can reference it as value of the traefik.http.middlewares.error-pages-middleware.errors.service=??? label - service name foo-test isnt static (that 'test' is name of my directory which contains docker-compose.yml) and it keep changing from time to time (especially when used with visual studio .dcproj)
So - is there any way to set name of service?
What did i try:
Google & doc. Nope, but maybe because i dont know what to ask.
Setting container_name: foo does not help at all.
Interestlingly, if i add label - traefik.http.services.foo.loadbalancer.server.port=80 it automagically name the traefik service as foo which is exactly what i want and everything works. But this feels like "Plan B" because i dont want to set port, i want to set the name of the service.
using traefic dynamic configuration
[http.services]
[http.services.foo.loadBalancer]
[[http.services.foo.loadBalancer.servers]]
url = "http://foo:80/"
should work (i didnt tested it) -- but again, i dont want to set whole url, i want to set the name of service...

Answer 1

Looks like (at least in v2.4) there isnt any other way than
labels:
- traefik.http.services.<<name_of_service>>.loadbalancer.server.port=80
AFAIK even in the documentation, there is only one mention:
labels:
- "traefik.http.routers.myproxy.rule=Host(`example.net`)"
# service myservice gets automatically assigned to router myproxy
- "traefik.http.services.myservice.loadbalancer.server.port=80"
(source: https://doc.traefik.io/traefik/routing/providers/docker/ )