furniture-3d-system-Wu/scripts/backup-db.sh

#!/bin/bash

# ============================================
# 数据库备份脚本
# ============================================
# 功能：备份 PostgreSQL 数据库
# 使用：./backup-db.sh [备份目录]
# ============================================

set -e  # 遇到错误立即退出

# 颜色输出
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m' # No Color

# 配置
BACKUP_DIR="${1:-./backups/database}"
TIMESTAMP=$(date +%Y%m%d-%H%M%S)
BACKUP_FILE="db-backup-${TIMESTAMP}.sql.gz"
LOG_FILE="backup-db-${TIMESTAMP}.log"

# 从环境变量读取数据库连接信息
if [ -f .env ]; then
  export $(cat .env | grep -v '^#' | xargs)
fi

DATABASE_URL="${DATABASE_URL:-}"

# 日志函数
log() {
  echo -e "${GREEN}[$(date +'%Y-%m-%d %H:%M:%S')]${NC} $1" | tee -a "${BACKUP_DIR}/${LOG_FILE}"
}

error() {
  echo -e "${RED}[$(date +'%Y-%m-%d %H:%M:%S')] ERROR:${NC} $1" | tee -a "${BACKUP_DIR}/${LOG_FILE}"
}

warn() {
  echo -e "${YELLOW}[$(date +'%Y-%m-%d %H:%M:%S')] WARNING:${NC} $1" | tee -a "${BACKUP_DIR}/${LOG_FILE}"
}

# 检查依赖
check_dependencies() {
  log "检查依赖..."
  
  if ! command -v pg_dump &> /dev/null; then
    error "pg_dump 未安装，请安装 PostgreSQL 客户端工具"
    exit 1
  fi
  
  if ! command -v gzip &> /dev/null; then
    error "gzip 未安装"
    exit 1
  fi
  
  log "✅ 依赖检查通过"
}

# 验证数据库连接
check_database_connection() {
  log "验证数据库连接..."
  
  if [ -z "$DATABASE_URL" ]; then
    error "DATABASE_URL 环境变量未设置"
    exit 1
  fi
  
  # 提取数据库连接信息
  if [[ $DATABASE_URL =~ postgresql://([^:]+):([^@]+)@([^:]+):([^/]+)/(.+) ]]; then
    DB_USER="${BASH_REMATCH[1]}"
    DB_PASS="${BASH_REMATCH[2]}"
    DB_HOST="${BASH_REMATCH[3]}"
    DB_PORT="${BASH_REMATCH[4]}"
    DB_NAME="${BASH_REMATCH[5]}"
  else
    error "DATABASE_URL 格式无效"
    exit 1
  fi
  
  # 测试连接
  export PGPASSWORD="$DB_PASS"
  if ! psql -h "$DB_HOST" -p "$DB_PORT" -U "$DB_USER" -d "$DB_NAME" -c "SELECT 1" &> /dev/null; then
    error "无法连接到数据库"
    exit 1
  fi
  
  log "✅ 数据库连接成功"
}

# 创建备份目录
create_backup_directory() {
  log "创建备份目录: ${BACKUP_DIR}"
  
  mkdir -p "${BACKUP_DIR}"
  
  if [ ! -d "${BACKUP_DIR}" ]; then
    error "无法创建备份目录"
    exit 1
  fi
  
  log "✅ 备份目录已创建"
}

# 检查磁盘空间
check_disk_space() {
  log "检查磁盘空间..."
  
  # 获取可用空间（MB）
  AVAILABLE_SPACE=$(df -m "${BACKUP_DIR}" | awk 'NR==2 {print $4}')
  
  # 估算数据库大小（MB）
  DB_SIZE=$(psql -h "$DB_HOST" -p "$DB_PORT" -U "$DB_USER" -d "$DB_NAME" -t -c "SELECT pg_database_size('$DB_NAME') / 1024 / 1024" | xargs)
  DB_SIZE=${DB_SIZE%.*}  # 取整
  
  # 需要至少 2 倍的数据库大小空间
  REQUIRED_SPACE=$((DB_SIZE * 2))
  
  log "数据库大小: ${DB_SIZE} MB"
  log "可用空间: ${AVAILABLE_SPACE} MB"
  log "需要空间: ${REQUIRED_SPACE} MB"
  
  if [ "$AVAILABLE_SPACE" -lt "$REQUIRED_SPACE" ]; then
    error "磁盘空间不足"
    exit 1
  fi
  
  log "✅ 磁盘空间充足"
}

# 执行备份
perform_backup() {
  log "开始备份数据库..."
  log "备份文件: ${BACKUP_FILE}"
  
  START_TIME=$(date +%s)
  
  # 执行备份并压缩
  if pg_dump -h "$DB_HOST" -p "$DB_PORT" -U "$DB_USER" -d "$DB_NAME" \
    --format=plain \
    --no-owner \
    --no-acl \
    --clean \
    --if-exists \
    | gzip > "${BACKUP_DIR}/${BACKUP_FILE}"; then
    
    END_TIME=$(date +%s)
    DURATION=$((END_TIME - START_TIME))
    
    log "✅ 备份完成，耗时: ${DURATION} 秒"
  else
    error "备份失败"
    exit 1
  fi
}

# 验证备份文件
verify_backup() {
  log "验证备份文件..."
  
  if [ ! -f "${BACKUP_DIR}/${BACKUP_FILE}" ]; then
    error "备份文件不存在"
    exit 1
  fi
  
  # 检查文件大小
  FILE_SIZE=$(du -h "${BACKUP_DIR}/${BACKUP_FILE}" | cut -f1)
  log "备份文件大小: ${FILE_SIZE}"
  
  # 验证 gzip 文件完整性
  if gzip -t "${BACKUP_DIR}/${BACKUP_FILE}" 2>/dev/null; then
    log "✅ 备份文件完整性验证通过"
  else
    error "备份文件损坏"
    exit 1
  fi
  
  # 生成 checksum
  CHECKSUM=$(sha256sum "${BACKUP_DIR}/${BACKUP_FILE}" | cut -d' ' -f1)
  echo "$CHECKSUM" > "${BACKUP_DIR}/${BACKUP_FILE}.sha256"
  log "✅ Checksum: ${CHECKSUM}"
}

# 清理旧备份
cleanup_old_backups() {
  log "清理旧备份..."
  
  # 保留最近 7 个备份
  KEEP_COUNT=7
  
  # 获取备份文件列表（按时间排序）
  BACKUP_FILES=($(ls -t "${BACKUP_DIR}"/db-backup-*.sql.gz 2>/dev/null || true))
  BACKUP_COUNT=${#BACKUP_FILES[@]}
  
  if [ "$BACKUP_COUNT" -gt "$KEEP_COUNT" ]; then
    DELETE_COUNT=$((BACKUP_COUNT - KEEP_COUNT))
    log "发现 ${BACKUP_COUNT} 个备份，删除最旧的 ${DELETE_COUNT} 个"
    
    for ((i=KEEP_COUNT; i<BACKUP_COUNT; i++)); do
      OLD_BACKUP="${BACKUP_FILES[$i]}"
      log "删除: $(basename $OLD_BACKUP)"
      rm -f "$OLD_BACKUP"
      rm -f "${OLD_BACKUP}.sha256"
    done
    
    log "✅ 清理完成"
  else
    log "当前有 ${BACKUP_COUNT} 个备份，无需清理"
  fi
}

# 生成备份摘要
generate_summary() {
  log "生成备份摘要..."
  
  cat > "${BACKUP_DIR}/backup-summary-${TIMESTAMP}.json" << EOF
{
  "timestamp": "$(date -Iseconds)",
  "backup_file": "${BACKUP_FILE}",
  "database": "${DB_NAME}",
  "host": "${DB_HOST}",
  "size": "$(du -b "${BACKUP_DIR}/${BACKUP_FILE}" | cut -f1)",
  "checksum": "$(cat "${BACKUP_DIR}/${BACKUP_FILE}.sha256")",
  "status": "success"
}
EOF
  
  log "✅ 备份摘要已生成"
}

# 主函数
main() {
  echo "========================================"
  echo "  数据库备份脚本"
  echo "========================================"
  echo ""
  
  check_dependencies
  check_database_connection
  create_backup_directory
  check_disk_space
  perform_backup
  verify_backup
  cleanup_old_backups
  generate_summary
  
  echo ""
  echo "========================================"
  log "🎉 备份成功完成！"
  echo "========================================"
  echo ""
  echo "备份文件: ${BACKUP_DIR}/${BACKUP_FILE}"
  echo "日志文件: ${BACKUP_DIR}/${LOG_FILE}"
  echo ""
}

# 执行主函数
main