emqx

#!/usr/bin/env bash
# -*- tab-width:4;indent-tabs-mode:nil -*-
# ex: ts=4 sw=4 et

set -e

DEBUG="${DEBUG:-0}"
if [ "$DEBUG" -eq 1 ]; then
    set -x
fi

RUNNER_ROOT_DIR="$(cd "$(dirname "$(readlink "$0" || echo "$0")")"/..; pwd -P)"
# shellcheck disable=SC1090
. "$RUNNER_ROOT_DIR"/releases/emqx_vars

EMQX_LICENSE_CONF=''
REL_NAME="emqx"
ERTS_PATH="$RUNNER_ROOT_DIR/erts-$ERTS_VSN/bin"
export EMQX_DESCRIPTION

RUNNER_SCRIPT="$RUNNER_BIN_DIR/$REL_NAME"
CODE_LOADING_MODE="${CODE_LOADING_MODE:-embedded}"
REL_DIR="$RUNNER_ROOT_DIR/releases/$REL_VSN"

WHOAMI=$(whoami)

# Make sure log directory exists
mkdir -p "$RUNNER_LOG_DIR"

# Make sure data directory exists
mkdir -p "$RUNNER_DATA_DIR"

export ROOTDIR="$RUNNER_ROOT_DIR"
export ERTS_DIR="$ROOTDIR/erts-$ERTS_VSN"
export BINDIR="$ERTS_DIR/bin"
export EMU="beam"
export PROGNAME="erl"
DYNLIBS_DIR="$RUNNER_ROOT_DIR/dynlibs"
ERTS_LIB_DIR="$ERTS_DIR/../lib"

# Fix bin permission for all erts bin files
# the 'x' attributes may get lost if the files are extracted from a relup package
find "$BINDIR" -exec chmod a+x {} \;

# cuttlefish try to read environment variables starting with "EMQX_"
export CUTTLEFISH_ENV_OVERRIDE_PREFIX='EMQX_'

usage() {
    local command="$1"

    case "$command" in
    start)
        echo "Start EMQX service in daemon mode"
        ;;
    stop)
        echo "Stop the running EMQX program"
        ;;
    console)
        echo "Boot up EMQX service in an interactive Erlang shell"
        echo "This command needs a tty"
        ;;
    console_clean)
        echo "This command does NOT boot up the EMQX service"
        echo "It only starts an interactive Erlang shell with all the"
        echo "EMQX code available"
        ;;
    foreground)
        echo "Start EMQX in foreground mode without an interactive shell"
        ;;
    pid)
        echo "Print out EMQX process identifier"
        ;;
    ping)
        echo "Check if the EMQX node is up and running"
        echo "This command exit with 0 silently if node is running"
        ;;
    escript)
        echo "Execute a escript using the Erlang runtime from EMQX package installation"
        echo "For example $REL_NAME escript /path/to/my/escript my_arg1 my_arg2"
        ;;
    attach)
        echo "This command is applicable when EMQX is started in daemon mode."
        echo "It attaches the current shell to EMQX's control console"
        echo "through a named pipe."
        echo "WARNING: try to use the safer alternative, remote_console command."
        ;;
    remote_console)
        echo "Start an interactive shell running an Erlang node which "
        echo "hidden-connects to the running EMQX node".
        echo "This command is mostly used for troubleshooting."
        ;;
    ertspath)
        echo "Print path to Erlang runtime dir"
        ;;
    rpc)
        echo "Usge $REL_NAME rpc MODULE FUNCTION [ARGS, ...]"
        echo "Connect to the EMQX node and make an Erlang RPC"
        echo "This command blocks for at most 60 seconds."
        echo "It exits with non-zero code in case of any RPC failure"
        echo "including connection error and runtime exception"
        ;;
    rpcterms)
        echo "Usge $REL_NAME rpcterms MODULE FUNCTION [ARGS, ...]"
        echo "Connect to the EMQX node and make an Erlang RPC"
        echo "The result of the RPC call is pretty-printed as an "
        echo "Erlang term"
        ;;
    root_dir)
        echo "Print EMQX installation root dir"
        ;;
    eval)
        echo "Evaluate an Erlang expression in the EMQX node"
        ;;
    versions)
        echo "List installed EMQX versions and their status"
        ;;
    unpack)
        echo "Usage: $REL_NAME unpack [VERSION]"
        echo "Unpacks a release package VERSION, it assumes that this"
        echo "release package tarball has already been deployed at one"
        echo "of the following locations:"
        echo "      releases/<relname>-<version>.zip"
        ;;
    install)
        echo "Usage: $REL_NAME install [VERSION]"
        echo "Installs a release package VERSION, it assumes that this"
        echo "release package tarball has already been deployed at one"
        echo "of the following locations:"
        echo "      releases/<relname>-<version>.zip"
        echo ""
        echo "     --no-permanent   Install release package VERSION but"
        echo "                      don't make it permanent"
        ;;
    uninstall)
        echo "Usage: $REL_NAME uninstall [VERSION]"
        echo "Uninstalls a release VERSION, it will only accept"
        echo "versions that are not currently in use"
        ;;
    upgrade)
        echo "Usage: $REL_NAME upgrade [VERSION]"
        echo "Upgrades the currently running release to VERSION, it assumes"
        echo "that a release package tarball has already been deployed at one"
        echo "of the following locations:"
        echo "      releases/<relname>-<version>.zip"
        echo ""
        echo "     --no-permanent   Install release package VERSION but"
        echo "                      don't make it permanent"
        ;;
    downgrade)
        echo "Usage: $REL_NAME downgrade [VERSION]"
        echo "Downgrades the currently running release to VERSION, it assumes"
        echo "that a release package tarball has already been deployed at one"
        echo "of the following locations:"
        echo "      releases/<relname>-<version>.zip"
        echo ""
        echo "     --no-permanent   Install release package VERSION but"
        echo "                      don't make it permanent"
        ;;
    *)
        echo "Usage: $REL_NAME COMMAND [help]"
        echo ''
        echo "Commonly used COMMANDs:"
        echo "  start:      Start EMQX in daemon mode"
        echo "  console:    Start EMQX in an interactive Erlang shell"
        echo "  foreground: Start EMQX in foreground mode without an interactive shell"
        echo "  stop:       Stop the running EMQX node"
        echo "  restart:    Restart the running EMQX node"
        echo "  ctl:        Administration commands, execute '$REL_NAME ctl help' for more details"
        echo ''
        echo "More:"
        echo "  Shell attach:  remote_console | attach"
        echo "  Up/Down-grade: upgrade | downgrade | install | uninstall"
        echo "  Install info:  ertspath | root_dir | versions"
        echo "  Runtime info:  pid | ping | versions"
        echo "  Config check:  check_conf"
        echo "  Advanced:      console_clean | escript | rpc | rpcterms | eval"
        echo ''
        echo "Execute '$REL_NAME COMMAND help' for more information"
        ;;
    esac
}

COMMAND="${1:-}"

if [ -z "$COMMAND" ]; then
    usage 'help'
    exit 1
elif [ "$COMMAND" = 'help' ]; then
    usage 'help'
    exit 0
fi

if [ "${2:-}" = 'help' ]; then
    ## 'ctl' command has its own usage info
    if [ "$COMMAND" != 'ctl' ]; then
        usage "$COMMAND"
        exit 0
    fi
fi

# Simple way to check the correct user and fail early
check_user() {
    # Validate that the user running the script is the owner of the
    # RUN_DIR.
    if [ "$RUNNER_USER" ] && [ "x$WHOAMI" != "x$RUNNER_USER" ]; then
        if [ "x$WHOAMI" != "xroot" ]; then
            echo "You need to be root or use sudo to run this command"
            exit 1
        fi
        CMD="\"$RUNNER_SCRIPT\" "
        for ARG in "$@"; do
            CMD="${CMD} \"$ARG\""
        done
        # This will drop priviledges into the runner user
        # It exec's in a new shell and the current shell will exit
        exec su - "$RUNNER_USER" -c "$CMD"
    fi
}

# Make sure the user running this script is the owner and/or su to that user
check_user "$@"
ES=$?
if [ "$ES" -ne 0 ]; then
    exit $ES
fi

# Echo to stderr on errors
echoerr() { echo "$*" 1>&2; }

die() {
    set +x
    echoerr "ERROR: $1"
    errno=${2:-1}
    exit "$errno"
}

assert_node_alive() {
    if ! relx_nodetool "ping" > /dev/null; then
        die "node_is_not_running!" 1
    fi
}

check_erlang_start() {
    # set ERL_CRASH_DUMP_BYTES to zero so it will not write a crash dump file
    env ERL_CRASH_DUMP_BYTES=0 "$BINDIR/$PROGNAME" -boot "$REL_DIR/start_clean" -eval "crypto:start(),halt()"
}

if ! check_erlang_start >/dev/null 2>&1; then
    BUILT_ON="$(head -1 "${REL_DIR}/BUILT_ON")"
    ## failed to start, might be due to missing libs, try to be portable
    export LD_LIBRARY_PATH="$DYNLIBS_DIR:$LD_LIBRARY_PATH"
    if ! check_erlang_start; then
        ## it's hopeless
        echoerr "FATAL: Unable to start Erlang."
        echoerr "Please make sure openssl-1.1.1 (libcrypto) and libncurses are installed."
        echoerr "Also ensure it's running on the correct platform,"
        echoerr "this EMQX release is built for $BUILT_ON"
        exit 1
    fi
    echoerr "There seem to be missing dynamic libs from the OS."
    echoerr "Using libs from ${DYNLIBS_DIR} instead."
    echoerr "NOTE: EMQX's rpm or deb package installation is recommended!"
fi

## backward compatible (old EMQX versions does this)
if [ -d "$ERTS_DIR/lib" ]; then
    export LD_LIBRARY_PATH="$ERTS_DIR/lib:$LD_LIBRARY_PATH"
fi

if [ -z "$WITH_EPMD" ]; then
    EPMD_ARG="-start_epmd false -epmd_module ekka_epmd -proto_dist ekka"
else
    PROTO_DIST=$(grep -E '^[ \t]*cluster.proto_dist[ \t]*=[ \t]*' "$RUNNER_ETC_DIR/emqx.conf" 2> /dev/null | tail -1 | awk -F"= " '{print $NF}')
    EPMD_ARG="-start_epmd true -proto_dist $PROTO_DIST"
fi

# Warn the user if ulimit -n is less than 1024
ULIMIT_F=$(ulimit -n)
if [ "$ULIMIT_F" -lt 1024 ]; then
    echo "!!!!"
    echo "!!!! WARNING: ulimit -n is ${ULIMIT_F}; 1024 is the recommended minimum."
    echo "!!!!"
fi

SED_REPLACE="sed -i "
case $(sed --help 2>&1) in
    *GNU*) SED_REPLACE="sed -i ";;
    *BusyBox*) SED_REPLACE="sed -i ";;
    *) SED_REPLACE="sed -i '' ";;
esac

# Get node pid
relx_get_pid() {
    if output="$(relx_nodetool rpcterms os getpid)"
    then
        # shellcheck disable=SC2001 # Escaped quote taken as closing quote in editor
        echo "$output" | sed -e 's/"//g'
        return 0
    else
        echo "$output"
        return 1
    fi
}

relx_get_nodename() {
    id="longname$(relx_gen_id)-${NAME}"
    "$BINDIR/erl" -boot "$REL_DIR/start_clean" -eval '[Host] = tl(string:tokens(atom_to_list(node()),"@")), io:format("~s~n", [Host]), halt()' -noshell "${NAME_TYPE}" "$id"
}

# Connect to a remote node
relx_rem_sh() {
    # Generate a unique id used to allow multiple remsh to the same node
    # transparently
    id="remsh$(relx_gen_id)-${NAME}"
    # Get the node's ticktime so that we use the same thing.
    TICKTIME="$(relx_nodetool rpcterms net_kernel get_net_ticktime)"

    # shellcheck disable=SC2086 # $EPMD_ARG is supposed to be split by whitespace
    # Setup remote shell command to control node
    exec "$BINDIR/erl" "$NAME_TYPE" "$id" -remsh "$NAME" -boot "$REL_DIR/start_clean" \
         -boot_var ERTS_LIB_DIR "$ERTS_LIB_DIR" \
         -setcookie "$COOKIE" -hidden -kernel net_ticktime "$TICKTIME" $EPMD_ARG
}

# Generate a random id
relx_gen_id() {
    od -t x -N 4 /dev/urandom | head -n1 | awk '{print $2}'
}

# Control a node
relx_nodetool() {
    command="$1"; shift
    export RUNNER_ROOT_DIR
    export REL_VSN

    ERL_FLAGS="$ERL_FLAGS $EPMD_ARG" \
    "$ERTS_DIR/bin/escript" "$ROOTDIR/bin/nodetool" "$NAME_TYPE" "$NAME" \
                                -setcookie "$COOKIE" "$command" "$@"
}

# Run an escript in the node's environment
relx_escript() {
    shift; scriptpath="$1"; shift
    export RUNNER_ROOT_DIR

    "$ERTS_DIR/bin/escript" "$ROOTDIR/$scriptpath" "$@"
}

# Output a start command for the last argument of run_erl
relx_start_command() {
    printf "exec \"%s\" \"%s\"" "$RUNNER_SCRIPT" \
           "$START_OPTION"
}

trim() {
    echo -e "${1}" | sed -e 's/^[[:space:]]*//' -e 's/[[:space:]]*$//'
}

# Function to generate app.config and vm.args
generate_config() {
    check_only="$1"
    if [ "$check_only" != "check_only" ]; then
      ## Delete the *.siz files first or it cann't start after
      ## changing the config 'log.rotation.size'
      rm -rf "${RUNNER_LOG_DIR}"/*.siz
    fi

    set +e
    if [ "${EMQX_LICENSE_CONF:-}" = "" ]; then
        CUTTLEFISH_OUTPUT="$("$ERTS_PATH"/escript "$RUNNER_ROOT_DIR"/bin/cuttlefish -v -i "$REL_DIR"/emqx.schema -c "$RUNNER_ETC_DIR"/emqx.conf -d "$RUNNER_DATA_DIR"/configs generate)"
    else
        CUTTLEFISH_OUTPUT="$("$ERTS_PATH"/escript "$RUNNER_ROOT_DIR"/bin/cuttlefish -v -i "$REL_DIR"/emqx.schema -i "${EMQX_LICENSE_CONF}" -c "$RUNNER_ETC_DIR"/emqx.conf -d "$RUNNER_DATA_DIR"/configs generate)"
    fi
    # shellcheck disable=SC2181
    RESULT=$?
    set -e
    if [ $RESULT -gt 0 ]; then
        echo "$CUTTLEFISH_OUTPUT"
        exit $RESULT
    fi
    ## transform a single line args list like '-config ... -args_file ... -vm_args ...' to lines and get path for each file respectively
    ## NOTE: the -args_file and -vm_args are the same file passed twice because args_file is used by beam, but not possible to get at runtime
    ## by calling init:get_arguments/0
    lines="$(echo "$CUTTLEFISH_OUTPUT" | tail -1 \
                    | sed -e $'s/-config/\\\nconfig=/g' \
                    | sed -e $'s/-args_file/\\\nargs_file=/g' \
                    | sed -e $'s/-vm_args/\\\nvm_args=/g')"
    CONFIG_FILE="$(trim "$(echo -e "$lines" | grep 'config=' | sed 's/config=//g')")"
    CUTTLE_GEN_ARG_FILE="$(trim "$(echo -e "$lines" | grep 'vm_args=' | sed 's/vm_args=//g')")"

    ## Merge cuttlefish generated *.args into the vm.args
    TMP_ARG_FILE="$RUNNER_DATA_DIR/configs/vm.args.tmp"
    cp "$RUNNER_ETC_DIR/vm.args" "$TMP_ARG_FILE"
    echo "" >> "$TMP_ARG_FILE"
    echo "-pa \"${REL_DIR}/consolidated\"" >> "$TMP_ARG_FILE"
    sed '/^#/d' "$CUTTLE_GEN_ARG_FILE" | sed '/^$/d' | while IFS='' read -r ARG_LINE || [ -n "$ARG_LINE" ]; do
        ARG_KEY=$(echo "$ARG_LINE" | awk '{$NF="";print}')
        ARG_VALUE=$(echo "$ARG_LINE" | awk '{print $NF}')
        if [ "$ARG_KEY" =  '' ]; then
            ## for the flags, e.g. -heart -emu_args etc
            ARG_KEY=$(echo "$ARG_LINE" | awk '{print $1}')
            ARG_VALUE=''
            TMP_ARG_KEY=$(grep "^$ARG_KEY" "$TMP_ARG_FILE" | awk '{print $1}')
            if [ "$TMP_ARG_KEY" = '' ]; then
                echo "$ARG_KEY" >> "$TMP_ARG_FILE"
            fi
        else
            TMP_ARG_VALUE=$(grep "^$ARG_KEY" "$TMP_ARG_FILE" | awk '{print $NF}')
            if [ "$ARG_VALUE" != "$TMP_ARG_VALUE" ] ; then
                if [ -n "$TMP_ARG_VALUE" ]; then
                    sh -c "$SED_REPLACE 's/^$ARG_KEY.*$/$ARG_LINE/' \"$TMP_ARG_FILE\""
                else
                    echo "$ARG_LINE" >> "$TMP_ARG_FILE"
                fi
            fi
        fi
    done

    if ! relx_nodetool chkconfig -config "$CONFIG_FILE"; then
        echoerr "Error reading $CONFIG_FILE"
        exit 1
    fi

    if [ "$check_only" = "check_only" ]; then
        rm -f "$TMP_ARG_FILE"
        rm -f "$CUTTLE_GEN_ARG_FILE"
        rm -f "$CONFIG_FILE"
    else
        mv -f "$TMP_ARG_FILE" "$CUTTLE_GEN_ARG_FILE"
    fi
}

# check if a PID is down
is_down() {
    PID="$1"
    if ps -p "$PID" >/dev/null; then
        # still around
        # shellcheck disable=SC2009 # this grep pattern is not a part of the progra names
        if ps -p "$PID" | grep -q 'defunct'; then
            # zombie state, print parent pid
            parent="$(ps -o ppid= -p "$PID" | tr -d ' ')"
            echo "WARN: $PID is marked <defunct>, parent:"
            ps -p "$parent"
            return 0
        fi
        return 1
    fi
    # it's gone
    return 0
}

wait_for() {
    local WAIT_TIME
    local CMD
    WAIT_TIME="$1"
    shift
    CMD="$*"
    while true; do
        if $CMD >/dev/null 2>&1; then
            return 0
        fi
        if [ "$WAIT_TIME" -le 0 ]; then
            return 1
        fi
        WAIT_TIME=$((WAIT_TIME - 1))
        sleep 1
    done
}

# Call bootstrapd for daemon commands like start/stop/console
bootstrapd() {
    if [ -e "$RUNNER_DATA_DIR/.erlang.cookie" ]; then
        chown "$RUNNER_USER" "$RUNNER_DATA_DIR"/.erlang.cookie
    fi
}

# check if a PID is down
is_down() {
    PID="$1"
    if ps -p "$PID" >/dev/null; then
        # still around
        # shellcheck disable=SC2009 # this grep pattern is not a part of the progra names
        if ps -p "$PID" | grep -q 'defunct'; then
            return 0
        fi
        return 1
    fi
    # it's gone
    return 0
}

wait_for() {
    local WAIT_TIME
    local CMD
    WAIT_TIME="$1"
    shift
    CMD="$*"
    while true; do
        if $CMD >/dev/null 2>&1; then
            return 0
        fi
        if [ "$WAIT_TIME" -le 0 ]; then
            return 1
        fi
        WAIT_TIME=$((WAIT_TIME - 1))
        sleep 1
    done
}

IS_BOOT_COMMAND='no'
case "$1" in
    start|start_boot)
        IS_BOOT_COMMAND='yes'
        ;;
    console|console_clean|console_boot)
        IS_BOOT_COMMAND='yes'
        ;;
    foreground)
        IS_BOOT_COMMAND='yes'
        ;;
    check_conf)
        IS_BOOT_COMMAND='yes'
        ;;
esac

if [ "$IS_BOOT_COMMAND" = 'no' ]; then
    # for non-boot commands, inspect vm.<time>.args for node name
    # shellcheck disable=SC2012
    LATEST_VM_ARGS_FILE="$(ls -t "$RUNNER_DATA_DIR"/configs/vm.*.args 2>/dev/null | head -1)"
    if [ -z "$LATEST_VM_ARGS_FILE" ]; then
        echoerr "There is no vm.*.args config file found in '$RUNNER_DATA_DIR/configs/'"
        echoerr "Please make sure the node is initialized (started for at least once)"
        exit 1
    fi
fi

if [ -z "$NAME_ARG" ]; then
    NODENAME="${EMQX_NODE_NAME:-}"
    # compatible with docker entrypoint
    [ -z "$NODENAME" ] && [ -n "$EMQX_NAME" ] && [ -n "$EMQX_HOST" ] && NODENAME="${EMQX_NAME}@${EMQX_HOST}"
    if [ -z "$NODENAME" ]; then
        if [ "$IS_BOOT_COMMAND" = 'no' ]; then
            NODENAME="$(grep -E '^-name' "$LATEST_VM_ARGS_FILE" | awk '{print $2}')"
        else
            # for boot commands, inspect emqx.conf for node name
            NODENAME=$("$ERTS_PATH"/escript "$RUNNER_ROOT_DIR"/bin/cuttlefish -i "$REL_DIR"/emqx.schema -c "$RUNNER_ETC_DIR"/emqx.conf get node.name)
        fi
    fi
    if [ -z "$NODENAME" ]; then
        echoerr "Failed to resolve emqx node name"
        if [ "$IS_BOOT_COMMAND" = 'yes' ]; then
            echoerr "Make sure runner has read permission on '$RUNNER_ETC_DIR/emqx.conf'"
        fi
        echoerr "Maybe override node name with environment variable ENQX_NODE_NAME='name@host.name'"
        echoerr "or, EMQX_NAME='name' and EMQX_HOST='host.name'"
        exit 1
    fi
    NAME_ARG="-name ${NODENAME# *}"
fi

# Extract the name type and name from the NAME_ARG for REMSH
NAME_TYPE="$(echo "$NAME_ARG" | awk '{print $1}')"
NAME="$(echo "$NAME_ARG" | awk '{print $2}')"
NODENAME="$(echo "$NAME" | awk -F'@' '{print $1}')"
if ! (echo "$NODENAME" | grep -q '^[0-9A-Za-z_\-]\+$'); then
    echo "Invalid node name, should be of format '^[0-9A-Za-z_-]+$'."
    exit 1
fi
export ESCRIPT_NAME="$NODENAME"

PIPE_DIR="${PIPE_DIR:-/$RUNNER_DATA_DIR/${WHOAMI}_erl_pipes/$NAME/}"

COOKIE="${EMQX_NODE_COOKIE:-}"
if [ -z "$COOKIE" ]; then
    if [ "$IS_BOOT_COMMAND" = 'yes' ]; then
        COOKIE=$("$ERTS_PATH"/escript "$RUNNER_ROOT_DIR"/bin/cuttlefish -i "$REL_DIR"/emqx.schema -c "$RUNNER_ETC_DIR"/emqx.conf get node.cookie)
    else
        COOKIE="$(grep -E '^-setcookie' "$LATEST_VM_ARGS_FILE" | awk '{print $2}')"
    fi
fi

if [ -z "$COOKIE" ]; then
    echoerr "Please set node.cookie in $RUNNER_ETC_DIR/emqx.conf or override from environment variable EMQX_NODE_COOKIE"
    exit 1
fi

cd "$ROOTDIR"

# User can specify an sname without @hostname
# This will fail when creating remote shell
# So here we check for @ and add @hostname if missing
case $NAME in
    *@*)
        # Nothing to do
        ;;
    *)
        NAME=$NAME@$(relx_get_nodename)
        ;;
esac
MNESIA_DATA_DIR="$RUNNER_DATA_DIR/mnesia/$NAME"

# Check the first argument for instructions
case "$1" in
    start|start_boot)
        # Make sure a node IS not running
        if relx_nodetool "ping" >/dev/null 2>&1; then
            echo "Node is already running!"
            exit 1
        fi
        # Bootstrap daemon command (check perms & drop to $RUNNER_USER)
        bootstrapd

        # this flag passes down to console mode
        # so we know it's intended to be run in daemon mode
        export _EMQX_START_MODE="$1"

        # Save this for later.
        CMD=$1
        case "$1" in
            start)
                shift
                START_OPTION="console"
                HEART_OPTION="start"
                ;;
            start_boot)
                shift
                START_OPTION="console_boot"
                HEART_OPTION="start_boot"
                ;;
        esac
        RUN_PARAM="$*"

        # Set arguments for the heart command
        set -- "$RUNNER_SCRIPT" "$HEART_OPTION"
        [ "$RUN_PARAM" ] && set -- "$@" "$RUN_PARAM"

        # Export the HEART_COMMAND
        HEART_COMMAND="$RUNNER_SCRIPT $CMD"
        export HEART_COMMAND

        ## See: http://erlang.org/doc/man/run_erl.html
        # Export the RUN_ERL_LOG_GENERATIONS
        export RUN_ERL_LOG_GENERATIONS=${RUN_ERL_LOG_GENERATIONS:-"5"}

        # Export the RUN_ERL_LOG_MAXSIZE
        export RUN_ERL_LOG_MAXSIZE=${RUN_ERL_LOG_MAXSIZE:-"10485760"}

        mkdir -p "$PIPE_DIR"

        "$BINDIR/run_erl" -daemon "$PIPE_DIR" "$RUNNER_LOG_DIR" \
                          "$(relx_start_command)"

        WAIT_TIME=${WAIT_FOR_ERLANG:-150}
        while [ "$WAIT_TIME" -gt 0 ]; do
            if ! relx_nodetool "ping" >/dev/null 2>&1; then
                WAIT_TIME=$((WAIT_TIME - 1))
                sleep 1
                continue
            fi
            sleep 1
            if relx_nodetool "ping" >/dev/null 2>&1; then
                echo "$EMQX_DESCRIPTION $REL_VSN is started successfully!"
                exit 0
            fi
        done && echo "$EMQX_DESCRIPTION $REL_VSN failed to start within ${WAIT_FOR_ERLANG:-150} seconds,"
        echo "see the output of '$0 console' for more information."
        echo "If you want to wait longer, set the environment variable"
        echo "WAIT_FOR_ERLANG to the number of seconds to wait."
        exit 1
        ;;

    stop)
        # Wait for the node to completely stop...
        PID="$(relx_get_pid)"
        if ! relx_nodetool "stop"; then
            echoerr "Graceful shutdown failed PID=[$PID]"
            exit 1
        fi
        WAIT_TIME="${EMQX_WAIT_FOR_STOP:-120}"
        if ! wait_for "$WAIT_TIME" 'is_down' "$PID"; then
            msg="dangling after ${WAIT_TIME} seconds"
            # also log to syslog
            logger -t "${REL_NAME}[${PID}]" "STOP: $msg"
            # log to user console
            echoerr "Stop failed, $msg"
            echo "ERROR: $PID is still around"
            ps -p "$PID"
            exit 1
        fi
        logger -t "${REL_NAME}[${PID}]" "STOP: OK"
        ;;

    restart|reboot)
        echo "$EMQX_DESCRIPTION $REL_VSN is stopped: $("$RUNNER_BIN_DIR"/emqx stop)"
        "$RUNNER_BIN_DIR"/emqx start
        ;;

    pid)
        ## Get the VM's pid
        if ! relx_get_pid; then
            exit 1
        fi
        ;;

    ping)
        ## See if the VM is alive
        if ! relx_nodetool "ping"; then
            exit 1
        fi
        ;;

    escript)
        ## Run an escript under the node's environment
        if ! relx_escript "$@"; then
            exit 1
        fi
        ;;

    attach)
        # Make sure a node IS running
        if ! relx_nodetool "ping" > /dev/null; then
            echo "Node is not running!"
            exit 1
        fi

        # Bootstrap daemon command (check perms & drop to $RUNNER_USER)
        bootstrapd

        shift
        exec "$BINDIR/to_erl" "$PIPE_DIR"
        ;;

    remote_console)
        # Make sure a node IS running
        if ! relx_nodetool "ping" > /dev/null; then
            echo "Node is not running!"
            exit 1
        fi

        # Bootstrap daemon command (check perms & drop to $RUNNER_USER)
        bootstrapd

        shift
        relx_rem_sh
        ;;

    upgrade|downgrade|install|unpack|uninstall)
        if [ -z "$2" ]; then
            echo "Missing version argument"
            echo "Usage: $REL_NAME $1 {version}"
            exit 1
        fi

        COMMAND="$1"; shift

        # Make sure a node IS running
        if ! relx_nodetool "ping" > /dev/null; then
            echo "Node is not running!"
            exit 1
        fi

        ERL_FLAGS="$ERL_FLAGS $EPMD_ARG" \
        exec "$BINDIR/escript" "$ROOTDIR/bin/install_upgrade.escript" \
             "$COMMAND" "{'$REL_NAME', \"$NAME_TYPE\", '$NAME', '$COOKIE'}" "$@"
        ;;

    versions)
        # Make sure a node IS running
        if ! relx_nodetool "ping" > /dev/null; then
            echo "Node is not running!"
            exit 1
        fi

        COMMAND="$1"; shift

        ERL_FLAGS="$ERL_FLAGS $EPMD_ARG" \
        exec "$BINDIR/escript" "$ROOTDIR/bin/install_upgrade.escript" \
             "versions" "{'$REL_NAME', \"$NAME_TYPE\", '$NAME', '$COOKIE'}" "$@"
        ;;

    console|console_clean|console_boot)
        # Bootstrap daemon command (check perms & drop to $RUNNER_USER)
        bootstrapd

        # .boot file typically just $REL_NAME (ie, the app name)
        # however, for debugging, sometimes start_clean.boot is useful.
        # For e.g. 'setup', one may even want to name another boot script.
        case "$1" in
            console)
                if [ -f "$REL_DIR/$REL_NAME.boot" ]; then
                  BOOTFILE="$REL_DIR/$REL_NAME"
                else
                  BOOTFILE="$REL_DIR/start"
                fi
                ;;
            console_clean)
                BOOTFILE="$REL_DIR/start_clean"
                ;;
            console_boot)
                shift
                BOOTFILE="$1"
                shift
                ;;
        esac

        # set before generate_config
        if [ "${_EMQX_START_MODE:-}" = '' ]; then
            export EMQX_LOG__TO="${EMQX_LOG__TO:-console}"
        fi

        #generate app.config and vm.args
        generate_config

        # Setup beam-required vars
        EMU="beam"
        PROGNAME="${0#*/}"

        export EMU
        export PROGNAME

        # Store passed arguments since they will be erased by `set`
        ARGS="$*"

        # shellcheck disable=SC2086 # $EPMD_ARG is supposed to be split by whitespace
        # Build an array of arguments to pass to exec later on
        # Build it here because this command will be used for logging.
        set -- "$BINDIR/erlexec" \
            -boot "$BOOTFILE" -mode "$CODE_LOADING_MODE" \
            -boot_var ERTS_LIB_DIR "$ERTS_LIB_DIR" \
            -mnesia dir "\"${MNESIA_DATA_DIR}\"" \
            -config "$CONFIG_FILE" \
            -args_file "$CUTTLE_GEN_ARG_FILE" \
            -vm_args "$CUTTLE_GEN_ARG_FILE" \
            $EPMD_ARG

        # Log the startup
        logger -t "${REL_NAME}[$$]" "$* -- ${1+$ARGS}"

        # Start the VM
        exec "$@" -- ${1+$ARGS}
        ;;

    foreground)
        # Bootstrap daemon command (check perms & drop to $RUNNER_USER)
        bootstrapd
        # start up the release in the foreground for use by runit
        # or other supervision services

        # set before generate_config
        export EMQX_LOG__TO="${EMQX_LOG__TO:-console}"

        #generate app.config and vm.args
        generate_config

        [ -f "$REL_DIR/$REL_NAME.boot" ] && BOOTFILE="$REL_NAME" || BOOTFILE=start
        FOREGROUNDOPTIONS="-noshell -noinput +Bd"

        # Setup beam-required vars
        EMU=beam
        PROGNAME="${0#*/}"

        export EMU
        export PROGNAME

        # Store passed arguments since they will be erased by `set`
        ARGS="$*"

        # shellcheck disable=SC2086 # $EPMD_ARG is supposed to be split by whitespace
        # Build an array of arguments to pass to exec later on
        # Build it here because this command will be used for logging.
        set -- "$BINDIR/erlexec" $FOREGROUNDOPTIONS \
            -boot "$REL_DIR/$BOOTFILE" -mode "$CODE_LOADING_MODE" \
            -boot_var ERTS_LIB_DIR "$ERTS_LIB_DIR" \
            -mnesia dir "\"${MNESIA_DATA_DIR}\"" \
            -config "$CONFIG_FILE" \
            -args_file "$CUTTLE_GEN_ARG_FILE" \
            -vm_args "$CUTTLE_GEN_ARG_FILE" \
            $EPMD_ARG

        # Log the startup
        logger -t "${REL_NAME}[$$]" "$* -- ${1+$ARGS}"

        # Start the VM
        exec "$@" -- ${1+$ARGS}
        ;;
    ertspath)
        echo "$ERTS_PATH"
        ;;
    check_conf)
        generate_config "check_only"
        INCLUDE_CONFS=$(< "$RUNNER_ETC_DIR/emqx.conf" grep "include" |awk '{print $2}'|xargs)
        if [ "$INCLUDE_CONFS" == "" ]; then
          echo "$RUNNER_ETC_DIR/emqx.conf is ok"
        else
          echo "$RUNNER_ETC_DIR/emqx.conf(include $INCLUDE_CONFS) is ok"
        fi
        ;;

    ctl)
        assert_node_alive
        shift
        relx_nodetool rpc_infinity emqx_ctl run_command "$@"
        ;;

    rpc)
        assert_node_alive
        shift
        relx_nodetool rpc "$@"
        ;;
    rpcterms)
        assert_node_alive
        shift
        relx_nodetool rpcterms "$@"
        ;;
    root_dir)
        assert_node_alive
        shift
        relx_nodetool "eval" 'code:root_dir()'
        ;;
    eval)
        assert_node_alive
        shift
        relx_nodetool "eval" "$@"
        ;;
    *)
        usage "$COMMAND"
        exit 1
        ;;
esac

exit 0