Service "nginx-proxy" uses an undefined network "nginx-proxy" - docker

Question

I am trying to run a WordPress site inside of a docker container on Ubuntu VPS using Nginx-Proxy.
I created the following docker-compose.yml file
version: '3.4'
services:
nginx-proxy:
image: jwilder/nginx-proxy
container_name: nginx-proxy
ports:
- 80:80
- 443:443
restart: always
networks:
- nginx-proxy
volumes:
- /var/run/docker.sock:/tmp/docker.sock:ro
- /etc/nginx/vhost.d:/etc/nginx/vhost.d:ro
- /etc/certificates:/etc/nginx/certs
wordpress:
image: wordpress
container_name: wordpress
restart: always
ports:
- 8080:80
environment:
- VIRTUAL_HOST=wordpress.domain.com
- VIRTUAL_PORT=5500
- WORDPRESS_DB_HOST=db
- WORDPRESS_DB_USER=db_username
- WORDPRESS_DB_PASSWORD=db_password
- WORDPRESS_DB_NAME=db_name
depends_on:
- nginx-proxy
- db
networks:
- nginx-proxy
volumes:
- wordpress:/var/www/html
ports:
- 5500:5500
expose:
- 5500
db:
image: mysql:latest
container_name: db
restart: always
environment:
MYSQL_DATABASE: db_name
MYSQL_USER: db_username
MYSQL_PASSWORD: db_password
MySQL_RANDOM_ROOT_PASSWORD: '1'
depends_on:
- nginx-proxy
networks:
- nginx-proxy
volumes:
- db:/var/lib/mysql
ports:
- 5600:5600
expose:
- 5600
volumes:
wordpress:
db:
Every time I run docker-compose up I get the following error
Service "nginx-proxy" uses an undefined network "nginx-proxy"
I created a network using the following command
docker network create nginx-proxy
Here is the output of docker network ls
Why do I get that error? How can I fix it?

Answer 1

Anything you name in a per-service networks: block needs to be declared in a top-level networks: block.
version: '3.4'
services:
nginx-proxy:
networks:
- nginx-proxy # <-- matches below
volumes: { ... }
networks:
nginx-proxy: # <-- matches above
# may be empty, but this block is required
If you don't declare any networks: at all, Compose creates a network named default and attaches containers to it. For almost all uses this is what you need. So it may be simpler to just delete the networks: blocks entirely.
version: '3.4'
services:
nginx-proxy:
image: jwilder/nginx-proxy
# No networks:; just use automatic [default]
(You similarly do not need to manually provide a container_name:, or to expose: ports at the Compose level.)