Please run service containers in dedicated network to reach all together
### Description
According to [the documentation](https://docs.gitlab.com/ce/ci/docker/using_docker_images.html#how-docker-integration-works) you just link (--link) service containers to runner.
Firstly linking [deprecated in docker](https://docs.docker.com/engine/userguide/networking/default_network/dockerlinks/).
Second it does not allow reach one service to another.
My intention use services for testing application to do not manage containers lifecycle and I have tried something similar to:
```yaml
main-build-job:
stage: build
script:
-- <something which build and push "${PRIVATE_DOCKER_REGISTRY}/ourapp:${CI_BUILD_REF}_${CI_PIPELINE_ID}">
test-rest:
stage: test
variables:
GIT_STRATEGY: "none"
services:
- ${PRIVATE_DOCKER_REGISTRY}/testdb:latest
- ${PRIVATE_DOCKER_REGISTRY}/ourapp:${CI_BUILD_REF}_${CI_PIPELINE_ID}
script:
- >
i=0; until sleep 1 && (( i++ )) && http --check-status --timeout 1 "http://egaisapp:8080/portal-api/rest/check/db/version"; do
[ $i -ge $WAIT_START_TIMEOUT_SEC ] && echo "Timeout wait APP start!" && exit 2
echo "Waiting APP start (res: $?). Attempt: $i"
done
- time ./gradlew --no-daemon --stacktrace :portal-api:rest-client:test
```
What problem there is `ourapp` container can't reach `testdb`
### Proposal
On start stage generate unique name as you do with runner containers and create network like `runner-713101cd-project-15-concurrent-network`. Then attach all containers (including runner) to it on start. And delete on job end with containers.
### Links / references
In https://gitlab.com/gitlab-org/gitlab-ce/issues/25000 I request much more expensive request which may supersede this one.
issue