基于 Vue3 与.NET Core 的企业级大文件断点续传及信创适配方案

2. 持久化断点续传引擎

// transfer-engine.ts
class PersistentUploader {
  private static INSTANCE: PersistentUploader;
  private uploadRecords: Map<string, UploadRecord> = new Map();

  // 单例模式确保全局唯一
  public static getInstance(): PersistentUploader {
    if (!this.INSTANCE) {
      this.INSTANCE = new PersistentUploader();
      // 初始化时恢复未完成传输
      window.addEventListener('beforeunload', () => this.saveAllRecords());
    }
    return this.INSTANCE;
  }

  // 使用 IndexedDB 存储传输记录（IE8 降级为 localStorage）
  private async getStorage(): Promise<StorageAdapter> {
    if (BrowserDetector.supportsIndexedDB()) {
      return new IndexedDBStorage('file-transfer-db');
    }
    return new LocalStorageAdapter();
  }

  public async uploadFile(file: File, config: UploadConfig): Promise<void> {
    const fileId = this.generateFileId(file);
    const storage = await this.getStorage();
    const record = await storage.get(fileId) || {
      fileId,
      chunks: Math.ceil(file.size / config.chunkSize),
      completed: 0,
      algorithm: config.algorithm
    };
    const task = new UploadTask(file, record, config);
    this.uploadRecords.set(fileId, record);

    // 注册恢复处理器
    task.on('progress', () => this.saveRecord(fileId, task.record));
    return task;
  }

  private async saveRecord(fileId: string, record: UploadRecord) {
    (await this.getStorage()).set(fileId, record);
  }
}

3. 信创浏览器事件桥接

// trusted-browser-adapter.js
(function() {
  // 检测是否为信创浏览器
  const isTrusted = /Qianxin|Longsen|Honglian/i.test(navigator.userAgent);
  if (!isTrusted) return;

  // 建立跨域通信通道
  const bridge = {
    receiveMessage: function(data) {
      // 处理来自信创浏览器扩展的消息
      if (data.type === 'FILE_SELECTED') {
        const event = new CustomEvent('trustedFileSelected', { detail: data.files });
        window.dispatchEvent(event);
      }
    },
    sendMessage: function(action, payload) {
      // 调用浏览器扩展 API
      if (window.trustedBrowserAPI) {
        window.trustedBrowserAPI.postMessage({ action, payload });
      }
    }
  };

  // 暴露给全局
  window.trustedBridge = bridge;
})();

三、后端接口集成（.NET Core 示例）

1. 文件分片上传控制器

// FileChunkController.cs
[ApiController]
[Route("api/file-transfer")]
public class FileChunkController : ControllerBase {
  private readonly IFileStorageService _storageService;
  private readonly IEncryptionService _encryptionService;

  [HttpPost("chunk")]
  public async Task<IActionResult> UploadChunk(
    [FromForm] IFormFile chunk,
    [FromForm] string fileId,
    [FromForm] int chunkIndex,
    [FromForm] string algorithm = "SM4") {

    // 验证分片
    if (chunk.Length == 0) return BadRequest();

    // 解密处理（根据配置）
    byte[] decryptedData = algorithm switch {
      "SM4" => _encryptionService.SM4Decrypt(await chunk.ToByteArray()),
      "AES" => _encryptionService.AESDecrypt(await chunk.ToByteArray()),
      _ => await chunk.ToByteArray()
    };

    // 存储分片（华为云 OBS 适配）
    var chunkPath = $"{fileId}/chunk-{chunkIndex}";
    await _storageService.SaveChunk(chunkPath, decryptedData);

    return Ok(new { status = "saved", chunkIndex, nextExpectedIndex = chunkIndex + 1 });
  }
}

2. 数据库动态适配层

// DatabaseAdapterFactory.cs
public static class DatabaseAdapterFactory {
  public static IFileMetaRepository GetAdapter(string dbType) {
    return dbType.ToLower() switch {
      "mysql" => new MySqlFileMetaRepository(),
      "oracle" => new OracleFileMetaRepository(),
      "dm" => new DamengFileMetaRepository(),      // 达梦数据库
      "kingbase" => new KingbaseFileMetaRepository(), // 人大金仓
      _ => throw new NotSupportedException($"Unsupported DB: {dbType}")
    };
  }
}

// 统一接口示例
public interface IFileMetaRepository {
  Task<FileMetadata> GetMetadata(string fileId);
  Task SaveMetadata(FileMetadata metadata);
}

四、国产化特殊处理

1. 龙芯 MIPS 架构优化

// loongson-optimizer.ts
export class LoongsonUploader extends BaseUploader {
  protected override calculateChunkSize(file: File): number {
    // 龙芯 CPU 单线程性能较弱，适当减小分片大小
    const isLoongson = navigator.hardwareConcurrency < 4;
    return isLoongson ? 2 * 1024 * 1024 : super.calculateChunkSize(file);
  }

  protected override async encryptChunk(data: Blob, algorithm: string): Promise<Blob> {
    // 使用 WebCrypto API 的 SM4 实现（需引入 polyfill）
    if (algorithm === 'SM4' && !crypto.subtle.supports('SM4')) {
      return this.fallbackSM4Encrypt(data); // 降级到 JavaScript 实现
    }
    return super.encryptChunk(data, algorithm);
  }
}

2. 华为云 OBS 信创版集成

// obs-client-adapter.js
class OBSAdaptor {
  constructor(config) {
    this.config = {
      ...config,
      // 信创环境特殊配置
      sslVerified: config.isTrustedEnv ? false : true,
      region: config.region || 'cn-north-4',
      // 国产化操作系统需要指定 SDK 版本
      sdkVersion: isNationalOS() ? 'obs-sdk-national-2.2.11' : 'obs-sdk-2.2.11'
    };
  }

  async uploadFile(file, options) {
    // 动态加载 SDK（避免打包体积过大）
    if (!window.OBS) {
      await this.loadScript(this.getSdkUrl());
    }
    const obs = new OBS({
      access_key_id: this.config.ak,
      secret_access_key: this.config.sk,
      endpoint: this.config.endpoint,
      use_ssl: this.config.sslVerified,
      // 国产化环境需要禁用某些特性
      disable_features: isNationalOS() ? ['multi_part_upload'] : []
    });

    return new Promise((resolve, reject) => {
      obs.putObject({
        Bucket: options.bucket,
        Key: options.key,
        Body: file,
        ContentType: options.mimeType,
        // 信创环境需要特殊头部
        ...(isNationalOS() && { 'x-obs-national-env': 'true' })
      }, (err, result) => {
        err ? reject(err) : resolve(result);
      });
    });
  }
}

五、实施路线与测试策略

1. 渐进式兼容测试
   • IE8: 使用 VirtualBox 搭建 Win7+IE8 测试环境
   • 信创浏览器：联系厂商获取测试授权
   • 国产化 OS: 申请华为云鲲鹏/飞腾开发者实验室资源
2. 国产化适配验证
   • 达梦数据库：通过 ODBC 驱动实现 ORM 映射
   • 人大金仓：使用 PostgreSQL 协议兼容模式
   • 统信 UOS: 通过 Deepin Wine 运行旧版 ActiveX 控件

性能基准测试