Docker-compose and node container as not the primary one - node.js

Question

I'm new to Docker and I've successfully set up the PHP/Apache/MySQL. But once I try to add the node container (in order to use npm) it always shuts the container down upon composing up. And yes, I understand that I can use node directly without involving docker, but I find it useful for myself.
And as for composer, I want to use volumes in the node container in order to persist node_modules inside of src folder.
I compose it up using docker-compose up -d --build command.
During composing it shows no errors (even node container seems to be successfully built).
If it might help, I can share the log file (it's too big to include it here).
PS. If you find something that can be improved, please let me know.
Thank you in advance!
Dockerfile
FROM php:7.2-apache
RUN apt-get update
RUN a2enmod rewrite
RUN apt-get install zip unzip zlib1g-dev
RUN docker-php-ext-install pdo pdo_mysql mysqli zip
RUN curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer
RUN composer global require laravel/installer
ENV PATH="~/.composer/vendor/bin:${PATH}"
docker-compose.yml
version: '3'
services:
app:
build:
.
volumes:
- ./src:/var/www/html
depends_on:
- mysql
- nodejs
ports:
- 80:80
mysql:
image: mysql:5.7
environment:
MYSQL_ROOT_PASSWORD: qwerty
phpmyadmin:
image: phpmyadmin/phpmyadmin
links:
- mysql:db
ports:
- 8765:80
environment:
MYSQL_ROOT_PASSWORD: qwerty
PMA_HOST: mysql
depends_on:
- mysql
nodejs:
image: node:9.11
volumes:
- ./src:/var/www/html

Answer 1

As this Dockerfile you are using shows, you are not actually runing any application in the node container so as soon as it builds and starts up - it shuts down because it has nothing else to do.
Solution is simple - provide a application that you want to run into the container and run it like:
I've modified a part of your compose file
nodejs:
image: node:9.11
command: node app.js
volumes:
- ./src:/var/www/html
Where app.js is the script in which your app is written, you are free to use your own name.
edit providing a small improvement you asked for
You are not waiting until your database is fully initialized (depends_on is not capable of that), so take a look at one of my previous answers dealing with that problem here