.docker/php7.3/Dockerfile
FROM php:7.3-alpine
COPY --from=mlocati/php-extension-installer /usr/bin/install-php-extensions /usr/bin/
COPY --from=composer/composer:latest-bin /composer /usr/bin/composer
ENV COMPOSER_ALLOW_SUPERUSER 1
WORKDIR /docker
# Workaround to keep container running
CMD ["tail", "-f", "/dev/null"]