#!/bin/bash
: '
 @vendor    Chorke Academia, Inc.
 @web       https://cdn.chorke.org/docs/academia
 @version   1.0.00
 @since     1.0.00
'

:<<EOF
if [[ -x "$(command -v curl)" ]];then \
sudo apt -qq update;\
export PYSPARK_PYTHON='/usr/bin/python3';\
export SPARK_MASTER='spark://ns12-pc04:7077';\
export SPARK_HOME='/opt/cli/spark-3.3.2-bin-hadoop3';\
export JAVA_HOME='/usr/lib/jvm/java-11-openjdk-amd64';\
bash <(curl -s 'https://cdn.chorke.org/exec/cli/bash/install/apache-spark/3.3.2-slave-debian.sh.txt');\
else printf 'curl \033[0;31mnot found! \033[0m:(\n';fi
EOF


:<<EOF
if [[ -x "$(command -v curl)" ]];then \
sudo apt -qq update;\
export PYSPARK_PYTHON='/usr/bin/python3';\
export SPARK_MASTER='spark://ns12-pc04:7077';\
export SPARK_HOME='/opt/cli/spark-3.3.2-bin-hadoop3';\
export JAVA_HOME='/usr/lib/jvm/java-17-openjdk-amd64';\
bash <(curl -s 'https://cdn.chorke.org/exec/cli/bash/install/apache-spark/3.3.2-slave-debian.sh.txt');\
else printf 'curl \033[0;31mnot found! \033[0m:(\n';fi
EOF


function validate(){
    export SPARK_HOME='/opt/cli/spark-3.3.2-bin-hadoop3'
    if [ -f '/etc/systemd/system/spark-slave.service' ];then
        printf '\napache-spark \033[0;31malready installed \033[0m:)\n'
        exit 0
    fi
    if [ ! -f "${JAVA_HOME}/bin/java" ]||[ ! -x "$(command -v java)" ];then
        printf '\njava \033[0;31mnot found! \033[0m:(\n'
        exit 0
    fi
    if [ ! -f "${PYSPARK_PYTHON}" ]||[ ! -x "$(command -v python3)" ];then
        printf '\npython3 \033[0;31mnot found! \033[0m:(\n'
        exit 0
    fi
}

function download(){
    if [ ! -d "${SPARK_HOME}" ];then
        if [ ! -d '/opt/cli' ];then sudo mkdir -p /opt/cli;fi
        sudo wget -cq https://archive.apache.org/dist/spark/spark-3.3.2/spark-3.3.2-bin-hadoop3.tgz -P /opt/cli/
        sudo tar -xzf /opt/cli/spark-3.3.2-bin-hadoop3.tgz -C /opt/cli/
        sudo rm  -rf  /opt/cli/spark-3.3.2-bin-hadoop3.tgz
        sudo mkdir -p ${SPARK_HOME}/etc
    fi
}

function approve(){
    sudo addgroup --quiet --system spark
    sudo adduser  --quiet --system --ingroup spark --no-create-home --disabled-password spark
    sudo chown -R spark:spark ${SPARK_HOME}
}

function install(){
    if [ ! -f "${SPARK_HOME}/etc/env" ];then
        sudo tee -a ${SPARK_HOME}/etc/env >/dev/null <<EOF
JAVA_HOME="${JAVA_HOME}"
SPARK_HOME="${SPARK_HOME}"
PYSPARK_PYTHON="${PYSPARK_PYTHON}"
EOF
    fi

    sudo tee -a /etc/systemd/system/spark-slave.service >/dev/null <<EOF
[Unit]
Description=Apache Spark Slave
Documentation=https://spark.apache.org/docs/3.3.2
Wants=network-online.target
After=network-online.target
AssertFileNotEmpty=${SPARK_HOME}/etc/env

[Service]
User=spark
Group=spark
Type=forking
SuccessExitStatus=143

WorkingDirectory=${SPARK_HOME}/sbin
EnvironmentFile=${SPARK_HOME}/etc/env
ExecStartPre=/bin/bash -c "if [ -z \"\${PYSPARK_PYTHON}\" ]; then echo \"Variable PYSPARK_PYTHON not set in ${SPARK_HOME}/etc/env\"; exit 1; fi"
ExecStartPre=/bin/bash -c "if [ -z \"\${SPARK_HOME}\" ]; then echo \"Variable SPARK_HOME not set in ${SPARK_HOME}/etc/env\"; exit 1; fi"
ExecStartPre=/bin/bash -c "if [ -z \"\${JAVA_HOME}\" ]; then echo \"Variable JAVA_HOME not set in ${SPARK_HOME}/etc/env\"; exit 1; fi"
ExecStartPost=/bin/bash -c "echo \$MAINPID > ${SPARK_HOME}/etc/spark-slave.pid"
ExecStart=${SPARK_HOME}/sbin/start-slave.sh ${SPARK_MASTER}
ExecStop=${SPARK_HOME}/sbin/stop-slave.sh

[Install]
WantedBy=multi-user.target
EOF
}

function launch(){
    sudo systemctl daemon-reload
    sudo systemctl enable spark-slave.service
    sudo systemctl start  spark-slave.service
    sudo systemctl status spark-slave.service
}

function init(){
    validate
    download
    approve
    install
    launch
}

init