bk-repo-start.sh

#!/bin/bash

set -eu
trap "on_ERR;" ERR
on_ERR (){
    local fn=$0 ret=$? lineno=${BASH_LINENO:-$LINENO}
    echo >&2 "ERROR $fn exit with $ret at line $lineno: $(sed -n ${lineno}p $0)."
}

if [ $# -lt 1 ]; then
    echo "Usage: $0 MS_NAME [OPTIONS-for-MS_NAME]"
    exit 1
fi

# 一些关键命令
OPENRESTY_CMD="/usr/local/openresty/nginx/sbin/nginx"
PRESTART_CMD="$(dirname "$0")/bk-repo-start-pre.sh"

# 检查是否为systemd启动, repo的systemd配置文件里会设置REPO_SYSTEMD=1
check_started_by_systemd (){
    [ "${PPID:-0}" = 1 ] && [ -n "${REPO_SYSTEMD:-}" ]
}

# 检查变量是否赋值. 提供变量名.
check_empty_var (){
    local k e=0
    for k in "$@" ; do
        if [ -z "${!k:-}" ]; then
            echo >&2 "var $k is empty or not set."
            ((++e))
        fi
    done
    return $e
}
# 检查进程存活.
check_pid_alive (){
    [ -d "/proc/$1/" ]
}

tip_file_exist (){
    local m="file exist" e=0
    [ -f "$1" ] || { m="file not exist"; e=1; }
    echo "$1: $m."
    return $e
}
tip_dir_exist (){
    local m="dir exist" e=0
    [ -d "$1" ] || { m="dir not exist"; e=1; }
    echo "$1: $m."
    return $e
}

# 启动网关.
start_repo__openresty (){
    $OPENRESTY_CMD -p "$PWD" -g "user $MS_USER;"
}

check_port_listen (){
    local patt_port_listen port=$1
    printf -v patt_port_listen "^ *[0-9]+: [0-9A-F]+:%04X 0+:0+ 0A " "$port"
    if cat /proc/net/tcp /proc/net/tcp6 | grep -E "$patt_port_listen"; then
        echo "ERROR: port $port is LISTENed by others."
        return 19
    fi
    return 0
}
# 探测微服务启动入口
detect_main (){
    # 探测是slim版还是fatjar. 后台启动. PID文件及日志路径保持一致.
    if [ -f "META-INF/MANIFEST.MF" ]; then
        java_env+=("CLASSPATH=$CLASSPATH")
        java_argv+=("-Dfatjar=/$MS_NAME/boot-$MS_NAME.jar")  # 兼容fatjar文件名匹配进程.
        java_run="$MAIN_CLASS"
    elif [ -f "boot-$MS_NAME.jar" ]; then
        java_run="-jar ./boot-$MS_NAME.jar"
    else
        echo >&2 "unsupported repo-proj dir: $PWD."
        return 31
    fi
}

# 检查服务启动成功. health接口为格式化后的, 要求整行匹配.
check_springboot_up (){
    local port="$1"
    curl -m 1 -sf "http://127.0.0.1:$port/management/health" 2>/dev/null | grep -qx '  "status" : "UP",'
}
# 等待服务启动成功.
wait_springboot_up (){
    local pid="$1" port="$2" msg="app is up. ^_^"
    local wait_count=40 wait_sec=3  # 等待app启动, 否则认为失败触发systemd的自动重启.
    SECONDS=0
    until check_springboot_up "$port"; do
        echo "wait_springboot_up $port: $wait_count: sleep ${wait_sec}s.";
        sleep "$wait_sec";
        let wait_count-- || { msg="wait timeout"; break; }
        check_pid_alive "$pid" || { msg="java is dead"; break; }
    done
    echo "wait_springboot_up $port: $wait_count: $msg."
    if check_springboot_up "$port"; then
        return 0
    else
        return 14
    fi
}

# 启动微服务.
start_repo__springboot (){
    check_empty_var MEM_OPTS DEVOPS_GATEWAY SPRING_CONFIG_LOCATION JAVA_TOOL_OPTIONS || return 1
    local pid_file="./logs/java.pid" java_pid=0
    local java_env=() java_argv=() java_run="" JAVA_OPTS=${JAVA_OPTS:-}
    # 端口LISTEN预检(重复启动检查).
    check_port_listen "$API_PORT" || return $?
    # 检查启动入口, 设置公共运行参数等.
    detect_main || return $?
    for k in LANG USER HOME SHELL LOGNAME PATH HOSTNAME LD_LIBRARY_PATH ${!JAVA_*} ${!SPRING_*} ; do
        if [ -n "${!k-}" ]; then java_env+=("$k=${!k}"); fi  # 如果定义, 则传递.
    done
    java_argv+=(
        "-Ddevops_gateway=$DEVOPS_GATEWAY"
        "-Dserver.port=$API_PORT"  # 强制覆盖配置文件里的端口.
        "-Dbksvc=bk-repo-$MS_NAME"
    )
    # 指定环境变量及参数, 启动PATH里的java.
    env -i "${java_env[@]}" java -server "${java_argv[@]}" \
        $MEM_OPTS $JAVA_OPTS $java_run &>./logs/bootstrap.log &
    java_pid=$!
    echo "$java_pid" > "$pid_file" || return 24
    echo "java pid is $java_pid."
    # 此处阻塞.
    if ! wait_springboot_up "$java_pid" "$API_PORT"; then
        echo "wait_springboot_up: unable to confirm app status from http://127.0.0.1:$API_PORT/management/health"
        echo "see $PWD/logs/bootstrap.log and $PWD/logs/$MS_NAME.log for details."
        return 14
    fi
}

# 模拟systemd时的预设环境: 加载env, 切换启动目录及用户.
load_systemd_env (){
    local env_file
    set -a
    for env_file in service.env start.env ; do
        if [ -f "./$env_file" ] ; then
            echo "load env_file: $env_file."
            source "./$env_file" || return 22
        fi
    done
    set +a
}

emulate_systemd_prerequisites (){
    local script_path=$(readlink -f "$0")  # 基于此脚本定位.
    if [ -n "${BK_REPO_HOME:-}" ] ; then
        echo "BK_REPO_HOME comes from env: $BK_REPO_HOME."
    else
        export BK_REPO_HOME=${script_path%/*/*}
        echo "guess BK_REPO_HOME=$BK_REPO_HOME."
    fi
    cd "$BK_REPO_HOME/$MS_NAME" || return 16
    load_systemd_env || return $?
    check_empty_var MS_USER || return 15  # env文件里必须定义MS_USER
    # gateway使用root启动nginx, 其worker为普通用户.
    if [ "$USER" != "${MS_USER:-no-user}" ] && [ "$MS_NAME" != "gateway" ]; then
        echo "please run this script using user: ${MS_USER:-}. example command:"
        echo "sudo -u $MS_USER $0 $MS_NAME ..."
        return 5
    fi
    echo "call pre-start: $PRESTART_CMD $*"
    $PRESTART_CMD "$MS_NAME" "$@" || return 20
    load_systemd_env  # systemd允许pre-start修改env. 故重新加载.
}

MS_NAME=${1:-}
shift
# 启动repo服务. 参数为单个微服务.
# 检查参数的服务名称.
# 如果检查到不是通过systemd调用的, 则调用pre-start.sh
if check_started_by_systemd; then
    echo "launched by systemd."
else
    echo "I am not launched by systemd, try to emulate systemd prerequisites."
    emulate_systemd_prerequisites "$@" || exit $?
fi
ret=0
# 如果存在专属函数, 则调用, 否则使用默认的.
case $MS_NAME in
    gateway) func=start_repo__openresty;;
    *) func=start_repo__springboot;;
esac
"$func" "$@" || ret=$? || true  # 收集退出码.
if [ -n "${REPO_SYSTEMD:-}" ]; then
    sleep 1  # 确保systemd正常回收journal.
fi
exit "$ret"