#!/bin/bash
# stop.sh - 優(yōu)雅停機(jī)腳本

APP_NAME="provider"
APP_PORT=8082
NACOS_SERVER="127.0.0.1:8848"

echo "開始優(yōu)雅停止 $APP_NAME..."

# 1. 獲取服務(wù)ip
get_nacos_registered_ip() {
    
    # 調(diào)用Nacos查詢接口
    local response=$(curl -s "http://${NACOS_SERVER}/nacos/v1/ns/instance/list?serviceName=${APP_NAME}")
    
    if [ $? -ne 0 ] || [ -z "$response" ]; then
        echo "查詢Nacos服務(wù)失敗" >&2
        return 1
    fi
    
    # 解析JSON獲取IP（需要jq工具）
    if command -v jq >/dev/null 2>&1; then
        local ip=$(echo "$response" | jq -r '.hosts[0].ip' 2>/dev/null)
        if [ "$ip" != "null" ] && [ -n "$ip" ]; then
            echo $ip
            return 0
        fi
    fi
    
    # 如果沒有jq，使用grep/awk解析
    local ip=$(echo "$response" | grep -o '"ip":"[^"]*' | cut -d'"' -f4 | head -1)
    if [ -n "$ip" ]; then
        echo $ip
        return 0
    fi
    
    echo "無法從Nacos響應(yīng)中解析IP" >&2
    return 1
}

LOCAL_IP=$(get_nacos_registered_ip)
echo "檢測到服務(wù)注冊IP: $LOCAL_IP"

# 2. 從Nacos下線服務(wù)
echo "從Nacos注銷服務(wù)..."
curl -X DELETE "${NACOS_SERVER}/nacos/v1/ns/instance?serviceName=${APP_NAME}&ip=${LOCAL_IP}&port=${APP_PORT}"

# 3. 等待流量切換
echo "等待流量切換(15秒)..."
sleep 15

# 4. 根據(jù)jar名稱查找應(yīng)用進(jìn)程，比如provider2
echo "查找應(yīng)用進(jìn)程..."
# 更精確的進(jìn)程查找方式
APP_PID=$(ps aux | grep "[j]ava.*provider2" | awk '{print $2}')

if [ -n "$APP_PID" ]; then
    echo "找到應(yīng)用進(jìn)程，PID: $APP_PID"
    
    # 5. 發(fā)送優(yōu)雅停止信號
    echo "發(fā)送優(yōu)雅停止信號..."
    kill -15 $APP_PID
    
    # 6. 等待進(jìn)程停止，最多30秒
    for i in {1..30}; do
        if kill -0 $APP_PID 2>/dev/null; then
            echo "等待應(yīng)用停止...($i/30)"
            sleep 1
        else
            echo "應(yīng)用已優(yōu)雅停止"
            exit 0
        fi
    done
    
    # 7. 強(qiáng)制停止
    echo "優(yōu)雅停止超時，強(qiáng)制停止"
    kill -9 $APP_PID
else
    echo "應(yīng)用未運(yùn)行"
fi

echo "停止腳本執(zhí)行完成"

server:
  shutdown: graceful

package com.example.provider;

import com.alibaba.cloud.nacos.registry.NacosRegistration;
import com.alibaba.cloud.nacos.registry.NacosServiceRegistry;
import org.apache.catalina.connector.Connector;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.web.embedded.tomcat.TomcatConnectorCustomizer;
import org.springframework.context.ApplicationListener;
import org.springframework.context.annotation.Lazy;
import org.springframework.context.event.ContextClosedEvent;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;
import java.util.concurrent.Executor;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

@Component
public class TomcatNacosGracefulShutdown implements TomcatConnectorCustomizer,
        ApplicationListener<ContextClosedEvent> {

    private static final Logger logger = LoggerFactory.getLogger(TomcatNacosGracefulShutdown.class);

    private volatile Connector connector;

    @Lazy
    @Resource
    private NacosServiceRegistry nacosServiceRegistry;

    @Lazy
    @Resource
    private NacosRegistration nacosRegistration;

    @Override
    public void customize(Connector connector) {
        this.connector = connector;
        logger.info("Tomcat連接器自定義配置完成");
    }

    @Override
    public void onApplicationEvent(ContextClosedEvent event) {
        logger.info("=== 開始Tomcat+Nacos優(yōu)雅停機(jī) ===");
        startGracefulShutdown();
    }

    public void startGracefulShutdown() {
        try {
            // 步驟1: Nacos注銷
            deregisterFromNacos();

            // 步驟2: 等待注冊中心傳播
            waitForRegistryPropagation();

            // 步驟3: 暫停Tomcat接收新請求
            pauseTomcat();

            // 步驟4: 等待活躍請求完成
            waitForActiveRequests();

            logger.info("=== Tomcat+Nacos優(yōu)雅停機(jī)完成 ===");

        } catch (Exception e) {
            logger.error("優(yōu)雅停機(jī)失敗", e);
        }
    }

    private void deregisterFromNacos() {
        if (nacosServiceRegistry != null && nacosRegistration != null) {
            try {
                logger.info("從Nacos注銷服務(wù)實(shí)例...");
                nacosServiceRegistry.deregister(nacosRegistration);
                logger.info("Nacos注銷成功: {}", nacosRegistration.getServiceId());
            } catch (Exception e) {
                logger.error("Nacos注銷失敗", e);
            }
        } else {
            logger.warn("Nacos注冊組件未找到，跳過注銷");
        }
    }

    private void waitForRegistryPropagation() {
        try {
            long waitTime = 15000;
            logger.info("等待注冊中心傳播: {}ms", waitTime);
            Thread.sleep(waitTime);
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
            logger.warn("等待過程被中斷");
        }
    }

    private void pauseTomcat() {
        if (connector != null) {
            logger.info("暫停Tomcat連接器，停止接收新請求");
            connector.pause();
        } else {
            logger.warn("Tomcat連接器未找到，無法暫停");
        }
    }

    private void waitForActiveRequests() {
        if (connector == null) {
            logger.warn("Tomcat連接器未找到，跳過等待");
            return;
        }

        Executor executor = connector.getProtocolHandler().getExecutor();
        if (executor instanceof ThreadPoolExecutor) {
            ThreadPoolExecutor threadPool = (ThreadPoolExecutor) executor;

            logger.info("等待活躍請求完成...");
            threadPool.shutdown();

            try {
                long maxWaitTime = 30000;
                if (!threadPool.awaitTermination(maxWaitTime, TimeUnit.MILLISECONDS)) {
                    logger.warn("等待請求超時，強(qiáng)制關(guān)閉線程池");
                    threadPool.shutdownNow();

                    if (!threadPool.awaitTermination(5000, TimeUnit.MILLISECONDS)) {
                        logger.error("線程池未能正常終止");
                    }
                } else {
                    logger.info("所有活躍請求處理完成");
                }
            } catch (InterruptedException e) {
                threadPool.shutdownNow();
                Thread.currentThread().interrupt();
                logger.warn("等待過程被中斷");
            }
        } else {
            logger.warn("無法獲取Tomcat線程池，跳過等待");
        }
    }

}