Docker: container state exit 0 - docker

Question

i have a problem with docker container.
That's my docker-compose file with 5 services
version: '3'
networks:
laravel:
services:
nginx:
image: nginx:stable-alpine
container_name: nginx
ports:
- "8088:80"
volumes:
- ./src:/var/www/html
- ./nginx/default.conf:/etc/nginx/conf.d/default.conf
depends_on:
- mysql
- php
networks:
- laravel
mysql:
image: mysql:5.7.22
container_name: mysql
restart: unless-stopped
tty: true
ports:
- "4306:3306"
environment:
MYSQL_DATABASE: homestead
MYSQL_USER: homestead
MYSQL_PASSWORD: secret
MYSQL_ROOT_PASSWORD: secret
SERVICE_TAGS: dev
SERVICE_NAME: mysql
networks:
- laravel
php:
build:
context: .
dockerfile: Dockerfile
container_name: php
volumes:
- ./src:/var/www/html
ports:
- "9000:9000"
networks:
- laravel
redis:
image: redis:5.0.0-alpine
restart: always
container_name: redis
ports:
- "6379:6379"
networks:
- laravel
composer:
image: composer:latest
container_name: composer
volumes:
- ./src:/var/www/html
tty: true
working_dir: /var/www/html
networks:
- laravel
then i run
docker-compose up -d
and then
docker-compose ps
to see my container and i always get the composer contaier down with code 0. that's the screenshot
:
can someone explain me why i can't put this container up. Thanks a lot

Answer 1

composer isn't a program that stays alive. It's a program that does specific some work and then exits.
There's not much purpose in keeping it "up", since it's not going to do anything like the other processes do (nginx intercepts web traffic and writes response, mysql accepts database connections and reads/writes from a database, php serves web content, redis can be connected to as a cache).