Example of Dockerfile for teaching

docker-compose.base.yml

services:
  db:
    image: mysql:5.7 

docker-compose.build.yml

services:
  db:
    build:
      context: ./dir
      dockerfile: Dockerfile-alternate

docker-compose.devices.yml

services:
  db:
    image: mysql:5.7 
    devices:
      - "/dev/ttyUSB0:/dev/ttyUSB0"

docker-compose.environment.yml

services:
  db:
    image: mysql:5.7
    environment:
      MYSQL_ROOT_PASSWORD: somewordpress

docker-compose.links.yml

services:
  db:
    container_name: db
    image: mysql:5.7
  php:
    image: php
    depends_on:
      - db
    links:
      - db
    

docker-compose.ports.yml

services:
  db:
    image: mysql:5.7
    ports:
      - "3306:3306"
      - "8000-8010:1234-1244"

docker-compose.volumes.yml

services:
  db:
    image: mysql:5.7
    volumes:
      - "data/config:/etc/mysql/config"
      - "dbdata:/var/data/mysql
      
volumes:
 dbdata:

docker-compose.yml

version: '3'
services:
   db:
     image: mysql:5.7
     volumes:
       - db_data:/var/lib/mysql
   wordpress:
     depends_on:
       - db
     image: wordpress:latest
     ports:
       - "8000:80"
     restart: always
volumes:
    db_data:

Dockerfile.php.example

FROM debian:latest

RUN apt-get update && apt-get upgrade -y && apt-get install -y php-cli && \ 
    mkdir /monDossier && mkdir /monDossier/share
   
COPY monScript.php /monDossier
ADD http://proof.ovh.net/files/1Mb.dat /monDossier

RUN mv /monDossier/monScript.php /monDossier/index.php

VOLUME /monDossier/share
EXPOSE 80
WORKDIR /monDossier
CMD php -S 0.0.0.0:80