由@Kamyl通知 https://github.com/nestjs/nest/issues/262 自从 v4.6.0 可以使用通用文件拦截器使用multer将文件上载到nestjs。

import { ... , UseInterceptors, FileInterceptor, UploadedFile } from '@nestjs/common'

... 

@UseInterceptors(FileInterceptor('file'))
async upload( @UploadedFile() file) {
  console.log(file)
}

这样,变量 file 将有一个 buffer

使用Multer选项

它还需要字段名作为第一个参数,然后是一个带有Multer选项的数组

import { ... , UseInterceptors, FileInterceptor, UploadedFile } from '@nestjs/common'
import { diskStorage } from 'multer'
import { extname } from 'path'

...

@UseInterceptors(FileInterceptor('file', {
  storage: diskStorage({
    destination: './uploads'
    , filename: (req, file, cb) => {
      // Generating a 32 random chars long string
      const randomName = Array(32).fill(null).map(() => (Math.round(Math.random() * 16)).toString(16)).join('')
      //Calling the callback passing the random name generated with the original extension name
      cb(null, `${randomName}${extname(file.originalname)}`)
    }
  })
}))
async upload( @UploadedFile() file) {
  console.log(file)
}

这样,变量 文件 将有一个 filename , destination 和 path .

这个 目的地 来自的参数 diskStorage 也可以是一个函数,具有参数,并且期望回调与 文件名 . 通过传递 磁盘存储 文件将自动保存到指定文件名通知的目标。

还可以通过使用 @UploadedFiles 和 FilesInterceptor (复数)

一种更简洁的方法是将配置提取到一个单独的文件中,然后在拦截器方法中调用它

import { extname } from 'path';
import { existsSync, mkdirSync } from 'fs';
import { diskStorage } from 'multer';
import { v4 as uuid } from 'uuid';
import { HttpException, HttpStatus } from '@nestjs/common';

// Multer configuration
export const multerConfig = {
    dest: process.env.UPLOAD_LOCATION,
};

// Multer upload options
export const multerOptions = {
    // Enable file size limits
    limits: {
        fileSize: +process.env.MAX_FILE_SIZE,
    },
    // Check the mimetypes to allow for upload
    fileFilter: (req: any, file: any, cb: any) => {
        if (file.mimetype.match(/\/(jpg|jpeg|png|gif)$/)) {
            // Allow storage of file
            cb(null, true);
        } else {
            // Reject file
            cb(new HttpException(`Unsupported file type ${extname(file.originalname)}`, HttpStatus.BAD_REQUEST), false);
        }
    },
    // Storage properties
    storage: diskStorage({
        // Destination storage path details
        destination: (req: any, file: any, cb: any) => {
            const uploadPath = multerConfig.dest;
            // Create folder if doesn't exist
            if (!existsSync(uploadPath)) {
                mkdirSync(uploadPath);
            }
            cb(null, uploadPath);
        },
        // File modification details
        filename: (req: any, file: any, cb: any) => {
            // Calling the callback passing the random name generated with the original extension name
            cb(null, `${uuid()}${extname(file.originalname)}`);
        },
    }),
};

然后在拦截器下面这样调用它

import { ... , UseInterceptors, FileInterceptor, UploadedFile } from '@nestjs/common'
import { diskStorage } from 'multer'
import { extname } from 'path'
import { multerOptions } from 'src/config/multer.config';
...

@Post('/action/upload')
@UseInterceptors(FileInterceptor('file', multerOptions))
async upload( @UploadedFile() file) {
  console.log(file)
}

使用Multer选项的最干净的实现

感谢您@VictorIvens为我们提供了最好的答案。

然而 ,我发现了以下内容 问题 在代码中。

• 导入调用 FileInterceptor 与不存在 @nestjs/common package int-NestJS的最新版本。
• 代码在我看来有点太乱了。

所以,到 简化 事情发生了,我想出了以下解决办法。

存储配置。ts

export const storage = diskStorage({
  destination: "./uploads",
  filename: (req, file, callback) => {
    callback(null, generateFilename(file));
  }
});

function generateFilename(file) {
  return `${Date.now()}.${extname(file.originalname)}`;
}

您的控制器。控制器。ts

import {
  Controller,
  Post,
  UseInterceptors,
  UploadedFile
} from "@nestjs/common";
import { FileInterceptor } from "@nestjs/platform-express";

import { diskStorage } from "multer";
import { extname } from "path";
import { storage } from "./storage.config"


@Controller()
export class YourController {
  @Post("upload") // API path
  @UseInterceptors(
    FileInterceptor(
      "file", // name of the field being passed
      { storage }
    )
  )
  async upload(@UploadedFile() file) {
    return file;
  }
}

**

2021更新

**

现在要这样做,您需要像这样导入FileInterceptor。。。

import { FileInterceptor } from '@nestjs/platform-express';

如果您通过API调用从用户处获取数据,则可以将数据保存为缓冲区,并使用访问内容 adm-zip . 下面是nest中的控制器方法实现。js。

@Post("/blackBoardUpload")
  @UseInterceptors(
    FileInterceptor('image', {
      storage: memoryStorage(),



      fileFilter: zipFileFilter,

    }),
  )
  async uploadedFile(@UploadedFile() file) {
    console.log(file)
    const response = {
      originalname: file.originalname,
      filename: file.filename,
    };
    var AdmZip = require('adm-zip');
    var zip = new AdmZip(file.buffer);

    var zipEntries = zip.getEntries();
    console.log(zipEntries.length);
    
    return {
      status: HttpStatus.OK,
      message: 'Received Zip file successfully!',
      data: response,
    };
  }

    Create a helper.ts file that rename your file and contains path
        
    export class Helper {
            static customFileName(req, file, cb) {
              const uniqueSuffix = Date.now() + '-' + Math.round(Math.random() * 1e9);
              let fileExtension = "";
              if(file.mimetype.indexOf("jpeg") > -1){
                  fileExtension = "jpg"
              }else if(file.mimetype.indexOf("png") > -1){
                  fileExtension = "png";
              }
              const originalName = file.originalname.split(".")[0];
              cb(null, originalName + '-' + uniqueSuffix+"."+fileExtension);
            }
           
            static destinationPath(req, file, cb) {
              cb(null, 'uploads/')
            }
          }

code for controller

import { Helper } from '../service/Helper';
import { diskStorage } from 'multer';
import {FileInterceptor} from '@nestjs/platform-express'
import {Controller, Post, Body, UseInterceptors, UploadedFile} from '@nestjs/common'

    @Post('upload')
    @UseInterceptors(
        FileInterceptor('picture', {
            storage: diskStorage({
                destination: Helper.destinationPath,
                filename: Helper.customFileName,
            }),
        }),
    )

    uploadFile(@UploadedFile() file: Express.Multer.File) {
    console.log(file);
    }

一种简单的方法是使用控制器。您需要定义上载控制器并将其添加到应用程序中。模块,这是控制器应该是什么的示例(后端):

@Controller()
export class Uploader {
  @Post('sampleName')
  @UseInterceptors(FileInterceptor('file'))
  uploadFile(@UploadedFile() file) {
  // file name selection 
    const path = `desired path`;
    const writeStream = fs.createWriteStream(path);  
    writeStream.write(file.buffer);
    writeStream.end();
    return {
      result: [res],
    };
  }
}

并通过前端提取调用控制器:

    fetch('controller address', {
          method: 'POST',
          body: data,
        })
          .then((response) => response.json())
          .then((success) => {
            // What to do when succeed 
});
          })
          .catch((error) => console.log('Error in uploading file: ', error));