This will only work for docker services running in bridge network mode. Home assistant runs in “host” network mode, so you will not be able to reference it from another docker container by container name as it is running outside of the docker network. You will have to spell out the host IP address and add :8123. This would be the same for any of your other containers running in host network mode.
I looked at your compose and do not see any network settings in the compose. Not sure how you hardcoded the IP of the caddy service, but I’m running the swag container and found the only way to keep the IP static and not move around on me is to add the IP into the docker compose.
This is my compose for the swag container defining a static IP
version: "2.1"
services:
swag:
image: linuxserver/swag
container_name: swag
restart: unless-stopped
cap_add:
- NET_ADMIN
volumes:
- /home/tim/docker/swag/config:/config
- /etc/localtime:/etc/localtime:ro
environment:
- PGID=1000
- PUID=1000
- [email protected]
- URL=yourdomain.duckdns.org
- SUBDOMAINS=wildcard
- VALIDATION=duckdns
- TZ=yourtimezone
- DUCKDNSTOKEN=yourtoken
- MAXMINDDB_LICENSE_KEY=yourkey #this is optional for location based IP banning
ports:
- "80:80"
- "443:443"
networks:
default:
ipv4_address: 172.21.0.2
More discussion about this as well on this thread - Nginx Reverse Proxy Set Up Guide – Docker - #285 by mwav3