smaller docker image

[skippy]

this cuts the size down to around 400megs; still not tiny but helpful. You can do a similar trick in ubuntu, and the resulting image is fairly close to the debian version

FROM debian:8

ENV BUILD_PACKAGES build-essential
ENV MAIN_PACKAGES wkhtmltopdf python-pip xvfb xauth xfonts-base

RUN apt-get update -qq \
  && apt-get install --no-install-recommends -yq $BUILD_PACKAGES $MAIN_PACKAGES \
  && apt-get remove -y $BUILD_PACKAGES \
  && apt-get autoremove -y \
  && apt-get clean \
  && rm -rf /var/lib/apt/lists/* \
  && truncate -s 0 /var/log/*log

ENTRYPOINT ["wkhtmltopdf"]

# Show the extended help
CMD ["-h"]

[prakashpp]

@skippy I will be happy to receive a PR on the same 👍