relocate special roles to api request

backend/src/models/requests/multipart.dto.ts

@@ -0,0 +1,64 @@
+import { BusboyFileStream } from '@fastify/busboy';
+import { HttpException } from '@nestjs/common';
+import { IsDefined, IsNotEmpty, IsString } from 'class-validator';
+import { MultipartFile } from 'fastify-multipart';
+
+export class MultiPartFileDto {
+  @IsString()
+  @IsNotEmpty()
+  fieldname: string;
+
+  @IsString()
+  @IsNotEmpty()
+  encoding: string;
+
+  @IsString()
+  @IsNotEmpty()
+  filename: string;
+
+  @IsString()
+  @IsNotEmpty()
+  mimetype: string;
+
+  @IsDefined()
+  toBuffer: () => Promise<Buffer>;
+
+  @IsDefined()
+  file: BusboyFileStream;
+
+  constructor(file: MultipartFile, exceptionOnFail: HttpException) {
+    this.fieldname = file.fieldname;
+    this.encoding = file.encoding;
+    this.filename = file.filename;
+    this.mimetype = file.mimetype;
+    this.toBuffer = async () => {
+      try {
+        return await file.toBuffer();
+      } catch (e) {
+        throw exceptionOnFail;
+      }
+    };
+
+    this.file = file.file;
+  }
+}
+
+export class MultiPartFieldDto {
+  @IsString()
+  @IsNotEmpty()
+  fieldname: string;
+
+  @IsString()
+  @IsNotEmpty()
+  encoding: string;
+
+  @IsString()
+  @IsNotEmpty()
+  value: string;
+
+  constructor(file: MultipartFile) {
+    this.fieldname = file.fieldname;
+    this.encoding = file.encoding;
+    this.value = (file as any).value;
+  }
+}