Last Updated: 2024-04-24

I could not get the Project B code running because it used an 8-year old PHP version not available on Mac anymore. Thus I reached for Docker.

I learned the following things:

• base containers for PHP (or whatever programming language you think of) do not necessarily contain the tools for installing dependencies (e.g. composer), so you might need to install them in your Dockerfile.
• if you don't set a working directory it will be some default like /var/www/html (typical root of a web server), therefore $ docker-compose run app composer install may not work since it may not be in the context of your actual app. Therefore set WORKDIR in your Dockerfile.
• if you run a command with docker you need the container name. But with docker-compose you use the service name implicitly given as the key under services in the docker-compose.yml file.
• you need to have RUN apt-get update if you plan on installing ANY apt-get packages. i.e. the container starts with no database of what is available. This saves space.
• all the basics like git, zip, unzip and friends will not be there (and need to be installed)