Generate and push image

docker login
docker build -t pokyunn/php:tagname .
docker push pokyunn/php:tagname

ex:

docker build -t pokyunn/php:7.2-fpm-alpine ./7.2/alpine/fpm
docker push pokyunn/php:7.2-fpm-alpine

Cleanup local

docker container prune -f
docker image prune -af