Change base image based on condition in dockerfile

Question

I want to send an argument USE_ALPINE to docker file if it is true i will use alpine image if it is false i will use debian image

the default value for USE_ALPINE i want to set it to false.

Answer 1

Make use of combination of ARG and FROM in Dockerfile.

You can use variables declared in ARG inside FROM statement.

ARG  APP_IMAGE=alpine:latest
FROM ${APP_IMAGE}
CMD  /path/to/mycode

And can also override this value using --build-arg option of docker build command.

docker build -t myapp:v1 --build-arg APP_IMAGE=busybox:latest .