How to extend Dockerimages via docker-compose - docker

Question

i try to extend my Basic Images from Webdevops.
I'll try to add the base-app to my Container that already exists.
Thats my docker-compose:
version: "3"
services:
base-app:
image: "webdevops/base-app"
restart: always
apache:
image: "webdevops/php-apache-dev:7.2"
container_name: apache
restart: always
ports:
- '80:80'
- '443:443'
depends_on:
- mysql
- base-app
volumes:
- "./:/app"
environment:
- XDEBUG_MODE=develop,debug
- XDEBUG_CLIENT_HOST=host.docker.internal
- XDEBUG_CLIENT_PORT=9003 # 9000=xdebug v2, 9003=v3
- XDEBUG_REMOTE_CONNECT_BACK=0
- XDEBUG_REMOTE_AUTOSTART=1
- XDEBUG_IDE_KEY=docker
- XDEBUG_START_WITH_REQUEST=trigger
extra_hosts:
- "host.docker.internal:host-gateway"
mysql:
image: "mysql:latest"
restart: always
container_name: mysql
ports:
- '3306:3306'
volumes:
- './mysql:/var/lib/mysql'
depends_on:
- base-app
environment:
MYSQL_ROOT_PASSWORD: 'xxxxx'
How to extend my Images with base-app?

Answer 1

You can extend any image using a Dockerfile. For example, you might write a Dockerfile
FROM webdevops/php-apache-dev:7.2
COPY . /app
You can do other steps as required, like RUNning an installation command or setting an alternate CMD you need this image to run. You generally should avoid putting host names or credentials of any sort into the Docker image, leave these as environment: settings in the Compose file.
In your docker-compose.yml file, use a build: block to indicate this image should be built. Do not include an image: line; unless you're specifically planning to push this extended image to a registry; and if you do it must have a different name from the base image.
services:
apache:
build: . # _instead of_ image:
restart: always
depends_on: [...]
ports: [...]
environment: [...]
# no volumes: since the code is already in the image
# container_name: is usually unnecessary