Docker container can not resolve .test domain running on localhost - docker

Question

I have magento running in a docker container using this tutorial (https://github.com/markshust/docker-magento).
The docker container is accessed via https://magento.test and this works fine in the browser. We have a script in magento that is trying to connect to https://magento.test from within the container but this fails with Could not resolve host: magento.test.
Basically the host can access magento.test and connect to the docker container. But the docker container can not connect to itself.
I have tried adding extra hosts to the docker-composer.yml (see below) but this has not worked. I am guessing the IP 127.0.0.1 is incorrect.
version: "3"
services:
app:
image: markoshust/magento-nginx:1.18-8
ports:
- "80:8000"
- "443:8443"
volumes: &appvolumes
- ~/.composer:/var/www/.composer:cached
- ~/.ssh/id_rsa:/var/www/.ssh/id_rsa:cached
- ~/.ssh/known_hosts:/var/www/.ssh/known_hosts:cached
- appdata:/var/www/html
- sockdata:/sock
- ssldata:/etc/nginx/certs
extra_hosts: &appextrahosts
## Selenium support, replace "magento.test" with URL of your site
- "magento.test:127.0.0.1"
phpfpm:
image: markoshust/magento-php:7.4-fpm-15
volumes: *appvolumes
env_file: env/phpfpm.env
#extra_hosts: *appextrahosts
db:
image: mariadb:10.4
command:
--max_allowed_packet=64M
--optimizer_use_condition_selectivity=1
--optimizer_switch="rowid_filter=off"
ports:
- "3306:3306"
env_file: env/db.env
volumes:
- dbdata:/var/lib/mysql
redis:
image: redis:6.2-alpine
ports:
- "6379:6379"
elasticsearch:
image: markoshust/magento-elasticsearch:7.16-0
ports:
- "9200:9200"
- "9300:9300"
environment:
- "discovery.type=single-node"
## Set custom heap size to avoid memory errors
- "ES_JAVA_OPTS=-Xms1g -Xmx1g"
## Avoid test failures due to small disks
## More info at https://github.com/markshust/docker-magento/issues/488
- "cluster.routing.allocation.disk.threshold_enabled=false"
- "index.blocks.read_only_allow_delete"
rabbitmq:
image: markoshust/magento-rabbitmq:3.9-0
ports:
- "15672:15672"
- "5672:5672"
volumes:
- rabbitmqdata:/var/lib/rabbitmq
env_file: env/rabbitmq.env
mailcatcher:
image: sj26/mailcatcher
ports:
- "1080:1080"
## Blackfire support, uncomment to enable
#blackfire:
# image: blackfire/blackfire:2
# ports:
# - "8307"
# env_file: env/blackfire.env
## Selenium support, uncomment to enable
#selenium:
# image: selenium/standalone-chrome-debug:3.8.1
# ports:
# - "5900:5900"
# extra_hosts: *appextrahosts
volumes:
appdata:
dbdata:
rabbitmqdata:
sockdata:
ssldata:
Any help would be greatly appreciated, thanks!

Answer 1

Does host network usage solve your problem?
services:
app:
image: markoshust/magento-nginx:1.18-8
network_mode: "host" # share host network
ports:
- "80:8000"
- "443:8443"
volumes: &appvolumes
- ~/.composer:/var/www/.composer:cached
- ~/.ssh/id_rsa:/var/www/.ssh/id_rsa:cached
- ~/.ssh/known_hosts:/var/www/.ssh/known_hosts:cached
- appdata:/var/www/html
- sockdata:/sock
- ssldata:/etc/nginx/certs
extra_hosts: &appextrahosts
## Selenium support, replace "magento.test" with URL of your site
- "magento.test:127.0.0.1"