version: '3.8'

services:
  # MySQL 5.7 备份服务
  mysql-backup:
    image: percona/percona-xtrabackup:2.4  # 使用 2.4 版本支持 MySQL 5.7
    container_name: mysql-backup
    restart: unless-stopped
    
    # 环境变量配置 - 请修改以下配置
    environment:
      # 🔗 远程 MySQL 5.7 服务器配置
      MYSQL_HOST: "rm-0jog99u32x2n4935j9o.mysql.ap-southeast-7.rds.aliyuncs.com"        # 远程 MySQL 服务器地址
      MYSQL_PORT: "13306"                         # MySQL 端口
      MYSQL_USER: "sysadmin"                  # 备份用户账号
      MYSQL_PASSWORD: "vxxa#RbOQajEbjaxyErgPU_p$Boit8a9"          # 备份用户密码
      MYSQL_VERSION: "5.7"                       # MySQL 版本
      
      # 📁 备份配置
      BACKUP_DIR: "/backup"                      # 容器内备份目录
      BACKUP_RETENTION_DAYS: "7"                 # 备份保留天数
      BACKUP_SCHEDULE: "0 2 * * *"               # 备份时间 (每天凌晨2点)
      
      # 🔧 备份选项
      BACKUP_TYPE: "full"                        # 备份类型: full(全量) / incremental(增量)
      COMPRESS_BACKUP: "true"                    # 是否压缩备份
      PARALLEL_THREADS: "2"                      # 并行线程数 (MySQL 5.7 建议使用较少线程)
      
    # 挂载卷配置
    volumes:
      - ./backup:/backup                         # 本地备份目录映射
      - ./scripts:/scripts                       # 备份脚本目录
      - ./logs:/logs                             # 日志目录
      - /etc/localtime:/etc/localtime:ro         # 时区同步
    
    # 网络配置
    networks:
      - backup-network
    
    # 启动命令 - 执行备份脚本
    command: >
      bash -c "
        echo 'MySQL 5.7 备份服务启动中...' &&
        echo '远程服务器: $${MYSQL_HOST}:$${MYSQL_PORT}' &&
        echo 'MySQL 版本: $${MYSQL_VERSION}' &&
        echo '备份用户: $${MYSQL_USER}' &&
        echo '备份目录: $${BACKUP_DIR}' &&
        echo '备份计划: $${BACKUP_SCHEDULE}' &&
        
        # 创建必要目录
        mkdir -p $${BACKUP_DIR} $${BACKUP_DIR}/full $${BACKUP_DIR}/incremental /logs &&
        
        # 安装 cron 和必要工具
        apt-get update && apt-get install -y cron gzip pv &&
        
        # 创建备份脚本
        cat > /scripts/backup.sh << 'EOF'
        #!/bin/bash
        set -e
        
        TIMESTAMP=$$(date +%Y%m%d_%H%M%S)
        BACKUP_PATH=$${BACKUP_DIR}/$${BACKUP_TYPE}/$${TIMESTAMP}
        
        echo \"[$$(date)] 开始 MySQL 5.7 备份到: $${BACKUP_PATH}\" >> /logs/backup.log
        
        # 创建备份目录
        mkdir -p $${BACKUP_PATH}
        
        # 测试连接
        echo \"[$$(date)] 测试 MySQL 连接...\" >> /logs/backup.log
        mysql -h$${MYSQL_HOST} -P$${MYSQL_PORT} -u$${MYSQL_USER} -p$${MYSQL_PASSWORD} -e \"SELECT 1;\" 2>> /logs/backup.log
        
        if [ $$? -ne 0 ]; then
          echo \"[$$(date)] 错误: 无法连接到 MySQL 服务器\" >> /logs/backup.log
          exit 1
        fi
        
        # 执行备份
        if [ \"$${BACKUP_TYPE}\" = \"full\" ]; then
          echo \"[$$(date)] 执行全量备份\" >> /logs/backup.log
          innobackupex \\
            --host=$${MYSQL_HOST} \\
            --port=$${MYSQL_PORT} \\
            --user=$${MYSQL_USER} \\
            --password=$${MYSQL_PASSWORD} \\
            --parallel=$${PARALLEL_THREADS} \\
            --compress \\
            --stream=tar \\
            $${BACKUP_PATH} 2>> /logs/backup.log | gzip > $${BACKUP_PATH}/backup.tar.gz
        else
          echo \"[$$(date)] 执行增量备份\" >> /logs/backup.log
          # 获取最新的全量备份作为基础
          LATEST_FULL=$$(ls -t $${BACKUP_DIR}/full/ | head -1)
          if [ -z \"$${LATEST_FULL}\" ]; then
            echo \"[$$(date)] 错误: 没有找到全量备份，无法执行增量备份\" >> /logs/backup.log
            exit 1
          fi
          
          innobackupex \\
            --host=$${MYSQL_HOST} \\
            --port=$${MYSQL_PORT} \\
            --user=$${MYSQL_USER} \\
            --password=$${MYSQL_PASSWORD} \\
            --parallel=$${PARALLEL_THREADS} \\
            --incremental \\
            --incremental-basedir=$${BACKUP_DIR}/full/$${LATEST_FULL} \\
            --compress \\
            --stream=tar \\
            $${BACKUP_PATH} 2>> /logs/backup.log | gzip > $${BACKUP_PATH}/backup.tar.gz
        fi
        
        # 验证备份文件
        if [ -f \"$${BACKUP_PATH}/backup.tar.gz\" ] && [ -s \"$${BACKUP_PATH}/backup.tar.gz\" ]; then
          echo \"[$$(date)] 备份成功: $${BACKUP_PATH}/backup.tar.gz\" >> /logs/backup.log
          echo \"[$$(date)] 备份文件大小: $$(du -h $${BACKUP_PATH}/backup.tar.gz | cut -f1)\" >> /logs/backup.log
        else
          echo \"[$$(date)] 错误: 备份文件创建失败或为空\" >> /logs/backup.log
          exit 1
        fi
        
        # 清理旧备份
        echo \"[$$(date)] 清理超过 $${BACKUP_RETENTION_DAYS} 天的备份\" >> /logs/backup.log
        find $${BACKUP_DIR} -type d -mtime +$${BACKUP_RETENTION_DAYS} -exec rm -rf {} + 2>/dev/null || true
        
        echo \"[$$(date)] 备份完成: $${BACKUP_PATH}\" >> /logs/backup.log
        EOF
        
        # 设置脚本执行权限
        chmod +x /scripts/backup.sh &&
        
        # 设置 cron 任务
        echo \"$${BACKUP_SCHEDULE} /scripts/backup.sh\" > /etc/cron.d/mysql-backup &&
        chmod 0644 /etc/cron.d/mysql-backup &&
        
        # 启动 cron 服务
        service cron start &&
        
        # 立即执行一次备份
        echo '执行初始备份...' &&
        /scripts/backup.sh &&
        
        # 保持容器运行
        echo 'MySQL 5.7 备份服务已启动，等待定时任务...' &&
        tail -f /logs/backup.log
      "
    
    # 资源限制
    deploy:
      resources:
        limits:
          memory: 1G
          cpus: '1.0'
        reservations:
          memory: 256M
          cpus: '0.25'

  # 备份监控服务 (可选)
  backup-monitor:
    image: nginx:alpine
    container_name: backup-monitor
    restart: unless-stopped
    ports:
      - "8080:80"                               # 监控界面端口
    volumes:
      - ./backup:/usr/share/nginx/html/backup:ro
      - ./monitor:/usr/share/nginx/html:ro
    networks:
      - backup-network
    depends_on:
      - mysql-backup

# 网络配置
networks:
  backup-network:
    driver: bridge

# 卷配置
volumes:
  backup-data:
    driver: local
  backup-logs:
    driver: local