anchor.diff:  # Dockerfile for Tor Relay Server with obfs4proxy
  -#
  -# This will install the Tor Debian package and obfs4proxy using
  -# the official instructions for installing Tor on Debian
  -#
  -# Usage:
  -#   docker run -d --init --restart=always -p 9001:9001 chriswayg/tor-server
   #
   # TODO:
   # - add GeoIP
  
positive.code:     TERM=xterm
  
  RUN set -x \
  	&& apt-get update \
  	&& DEBIAN_FRONTEND=noninteractive apt-get install --no-install-recommends --no-install-suggests -y \
        apt-transport-https \
  
negative.code: 		APT_KEY_DONT_WARN_ON_DANGEROUS_USAGE="True" apt-key adv --keyserver "$server" --keyserver-options timeout=10 --recv-keys "$GPGKEY" && found=yes && break; \
  	done; \
  	test -z "$found" && echo >&2 "error: failed to fetch GPG key $GPGKEY" && exit 1; \
    apt-get remove --purge --auto-remove -y gnupg && apt-get clean && rm -rf /var/lib/apt/lists/* && \
    \
    echo "deb https://deb.torproject.org/torproject.org stretch main"   >  /etc/apt/sources.list.d/tor-apt-sources.list && \
    echo "deb http://deb.torproject.org/torproject.org obfs4proxy main" >> /etc/apt/sources.list.d/tor-apt-sources.list && \
  # Install tor and obfs4proxy & backup torrc
    apt-get update && \
    DEBIAN_FRONTEND=noninteractive apt-get install --no-install-recommends --no-install-suggests -y \
      tor \
      deb.torproject.org-keyring \
      obfs4proxy && \
    mv -v /etc/tor/torrc /etc/tor/torrc.default && \
    apt-get clean && rm -rf /var/lib/apt/lists/*
  
  # Copy Tor configuration file
  COPY ./config/torrc /etc/tor/torrc
  