Class FileStorageAdapter

worker/src/adapters/file-storage.adapter.ts:10–125

 * Adapter that implements IFileStorageService using MinIO + PostgreSQL
 */
export class FileStorageAdapter implements IFileStorageService {
  constructor(
    private minioClient: Client,
    private db: NodePgDatabase<typeof schema>,
    private bucketName: string,
  ) {}

  async downloadFile(fileId: string): Promise<{
    buffer: Buffer;
    metadata: {
      id: string;
      fileName: string;
      mimeType: string;
      size: number;
    };
  }> {
    // Get metadata from database
    const [file] = await this.db
      .select()
      .from(schema.files)
      .where(eq(schema.files.id, fileId))
      .limit(1);

    if (!file) {
      throw new NotFoundError(`File not found: ${fileId}`, {
        resourceType: 'file',
        resourceId: fileId,
      });
    }

    // Download from MinIO
    const stream = await this.minioClient.getObject(this.bucketName, file.storageKey);

    // Convert stream to buffer
    const chunks: Buffer[] = [];
    for await (const chunk of stream) {
      chunks.push(Buffer.from(chunk));
    }
    const buffer = Buffer.concat(chunks);

    return {
      buffer,
      metadata: {
        id: file.id,
        fileName: file.fileName,
        mimeType: file.mimeType,
        size: file.size,
      },
    };
  }

  async getFileMetadata(fileId: string): Promise<{
    id: string;
    fileName: string;
    mimeType: string;
    size: number;
    uploadedAt: Date;
  }> {