FROM python:3.6-alpine

ENV SPARK_VERSION="2.4.8" \
    HADOOP_VERSION="2.7" \
    GRAPHFRAMES_VERSION="0.8.1-spark2.4-s_2.11" \
    APACHE_MIRROR="https://dlcdn.apache.org" \
    SPARK_INSTALL="/usr/local"

RUN apk add --no-cache \
        bash \
        openjdk8-jre \
        tini

RUN apk add --no-cache --virtual .fetch-deps \
        wget \
        tar

# download, install, and symlink spark
RUN cd $SPARK_INSTALL && \
    wget -q --show-progress --progress=bar:force:noscroll $APACHE_MIRROR/spark/spark-$SPARK_VERSION/spark-$SPARK_VERSION-bin-hadoop$HADOOP_VERSION.tgz 2>&1 && \
    tar xzf spark-$SPARK_VERSION-bin-hadoop$HADOOP_VERSION.tgz && \
    ln -s spark-$SPARK_VERSION-bin-hadoop$HADOOP_VERSION spark && \
    rm -f spark-$SPARK_VERSION-bin-hadoop$HADOOP_VERSION.tgz

# download and install graphframes
 RUN cd $SPARK_INSTALL/spark/jars && \
    wget -q --show-progress --progress=bar:force:noscroll https://repos.spark-packages.org/graphframes/graphframes/$GRAPHFRAMES_VERSION/graphframes-$GRAPHFRAMES_VERSION.jar

RUN apk del .fetch-deps && \
    rm -rf /tmp/* && \
    rm -rf /var/cache/* && \
    rm -rf /root/.cache

COPY start-master.sh start-worker.sh /usr/local/bin/

# these need to be separate because you can't reference prior environment
# variables in the same ENV block
ENV SPARK_HOME="$SPARK_INSTALL/spark" \
    SPARK_HOSTNAME="localhost" \
    SPARK_MASTER_PORT="7077" \
    SPARK_MASTER_WEBUI_PORT="8080"

COPY spark-defaults.conf $SPARK_HOME/conf

ENV SPARK_MASTER="spark://$SPARK_HOSTNAME:$SPARK_MASTER_PORT"

# Spark doesn't seem to respond directly to SIGTERM as the exit status is
# for SIGKILL (137), after a pause. Presumably docker-compose down times out.
# Using tini gives immediate exit with status 143 (SIGTERM).
ENTRYPOINT ["/sbin/tini", "--"]

CMD ["/usr/local/bin/start-master.sh"]