FROM alpine:3.5 MAINTAINER First O'Last # comment run echo \ 123 $bar RUN apk --update add rsync dumb-init # Test env with both syntax ENV FOO = "BAR" ENV FOO \ "BAR" COPY foo "bar" COPY foo \ "bar" HEALTHCHECK \ --interval=5m --timeout=3s \ CMD curl -f http://localhost/ || exit 1 # ONBUILD keyword, then with linebreak ONBUILD ADD . /app/src ONBUILD \ RUN echo 123 $bar # Potential JSON array parsing, mixed with linebreaks VOLUME \ /foo VOLUME \ ["/bar"] VOLUME ["/bar"] VOLUME /foo CMD ["foo", "bar"]