entrypoint.sh

#!/usr/bin/env bash

#!/bin/bash
#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

# echo commands to the terminal output
set -ex

# Check whether there is a passwd entry for the container UID
myuid=$(id -u)
mygid=$(id -g)
# turn off -e for getent because it will return error code in anonymous uid case
set +e
uidentry=$(getent passwd $myuid)
set -e

# If there is no passwd entry for the container UID, attempt to create one
if [ -z "$uidentry" ] ; then
    if [ -w /etc/passwd ] ; then
        echo "$myuid:x:$myuid:$mygid:${SPARK_USER_NAME:-anonymous uid}:${SPARK_HOME}:/bin/false" >> /etc/passwd
    else
        echo "Container ENTRYPOINT failed to add passwd entry for anonymous UID"
    fi
fi

###Todo: ensure that MAHOUT_HOME is properly established as an env var.
SPARK_CLASSPATH="$SPARK_CLASSPATH:${SPARK_HOME}/jars/*:${$MAHOUT_HOME}/lib/*"
env | grep SPARK_JAVA_OPT_ | sort -t_ -k4 -n | sed 's/[^=]*=\(.*\)/\1/g' > /tmp/java_opts.txt
readarray -t SPARK_EXECUTOR_JAVA_OPTS < /tmp/java_opts.txt

if [ -n "$SPARK_EXTRA_CLASSPATH" ]; then
  SPARK_CLASSPATH="$SPARK_CLASSPATH:$SPARK_EXTRA_CLASSPATH"
fi



if ! [ -z ${HADOOP_CONF_DIR+x} ]; then
  SPARK_CLASSPATH="$HADOOP_CONF_DIR:$SPARK_CLASSPATH:$MAHOUT_CLASSPATH";
fi

case "$1" in
  driver)
    shift 1
    CMD=(
      "$SPARK_HOME/bin/spark-submit"
      --conf "spark.driver.bindAddress=$SPARK_DRIVER_BIND_ADDRESS"
      --conf "spark.executor.extraLibraryPath"=\
         "${MAHOUT_HOME}/lib/mahout-spark_*-dependency-reduced.jar"
      --deploy-mode client
      "$@"
    )
    ;;
  executor)
    shift 1
    CMD=(
      ${JAVA_HOME}/bin/java
      "${SPARK_EXECUTOR_JAVA_OPTS[@]}"
      -Xms$SPARK_EXECUTOR_MEMORY
      -Xmx$SPARK_EXECUTOR_MEMORY
      -cp "$SPARK_CLASSPATH:$MAHOUT_CLASSPATH"
      org.apache.spark.executor.CoarseGrainedExecutorBackend
      --driver-url $SPARK_DRIVER_URL
      --executor-id $SPARK_EXECUTOR_ID
      --conf spark.executor.extraLibraryPath=\
        "$MAHOUT_HOME/lib/mahout-spark_*-dependency-reduced.jar"
      --cores $SPARK_EXECUTOR_CORES
      --app-id $SPARK_APPLICATION_ID
      --hostname $SPARK_EXECUTOR_POD_IP
    )
    ;;

  *)
    echo "Non-spark-on-k8s command provided, proceeding in pass-through mode..."
    CMD=("$@")
    ;;
esac

# Execute the container CMD under tini for better hygiene
exec /sbin/tini -s -- "${CMD[@]}"