.gitlab-ci.yml

image: ondrejsika/ci

variables:
    COMPOSE_PROJECT_NAME: p$CI_PIPELINE_ID
    COMPOSE_FILE: docker-compose.yml:docker-compose-test.yml

stages:
    - build
    - test

before_script:
    - docker login $CI_REGISTRY -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD


build:
    stage: build
    script:
        - docker-compose build
        - docker-compose push

test:
    stage: test
    script:
        - docker-compose pull
        - docker-compose up --no-build --abort-on-container-exit test
    after_script:
        - docker-compose down --volumes

docker-compose-traefik.yml

version: '3.7'
services:
    redis:
        image: redis
    counter:
        build: .
        image: reg.istry.cz/ondrej/counter
        depends_on: 
            - redis
        labels: 
            traefik.enable: true 
            traefik.frontend.rule: Host:counter.127.0.0.1.xip.io
    traefik:
        image: traefik:alpine
        command: |
            --web \
            --docker \
            --docker.watch \
            --entryPoints="Name:http Address::80" \
            --docker.exposedbydefault=false
        ports:
            - "80:80"
            - "8080:8080"
        volumes:
            - /var/run/docker.sock:/var/run/docker.sock

docker-compose-yaml-anchors.yml

version: '3.7'

x-service-template: &service-template
    image: debian
    command: env
    environment: &service-env-template
        A: 1
        B: 2

services:
    service1:
        <<: *service-template
        environment:
            <<: *service-env-template
            C: 3a
    service2:
        <<: *service-template
        environment:
            <<: *service-env-template
            C: 3b