java - 上传文件， Angular Spring 启动

Question

我需要使用 Angular 和 Spring Boot 上传文件。

Angular 服务:

 const httpOptions = {
      headers: new HttpHeaders({ 'Content-Type': 'application/json;multi-part/form-data'})
    };

addProduct(productRequest: ProductRequest, creator: string, tradeReference: string, selectedImage: File) {

    const trimCreator = creator.trim();
    const trimTradeReference = tradeReference.trim();   

    const formData =  new FormData();
    formData.append('images', selectedImage);


    return this.http.post<any>(baseUrl + '/addProduct', {formData, productRequest, trimCreator, trimTradeReference} , httpOptions)
      .pipe(
        catchError(this.handleError)
      );
  }

我的后端 Rest 服务如下:

    @ApiOperation(value = "add product", response = Iterable.class)
    @ApiResponses(value = { @ApiResponse(code = 200, message = "Successfully added product") })
    @PostMapping("/addProduct")
    public void addProduct(@RequestPart(value = "images") MultipartFile[] images,
                            @RequestPart(value = "product") Product product,
                            @RequestPart(value = "creator") @ApiParam(value = "creator") String creator,
                            @RequestPart(value = "tradeReference") @ApiParam(value = "tradeReference") String tradeReference
                            ) throws Exception {

        Arrays.asList(images)
                .stream()
                .forEach(image -> uploadImages(image, product));
        traderServices.addProduct(product, creator, tradeReference);
    }

错误:

{"timestamp":"2020-04-23T13:35:03.114+0000","status":500,"error":"Internal Server Error","message":"Current request is not a multipart request","trace":"org.springframework.web.multipart.MultipartException: Current request is not a multipart request\r\n\tat org.springframework.web.servlet.mvc.method.annotation.RequestPartMethodArgumentResolver.resolveArgument(RequestPartMethodArgumentResolver.java:158)\r\n\tat ,"path":"/api/trader/addProduct"}

我尝试像这样更新 PostMapping

@PostMapping(value = "/'addProduct", consumes = {MediaType.MULTIPART_FORM_DATA_VALUE, MediaType.APPLICATION_JSON_VALUE})

我还删除了 Angular 服务中的消耗信息和 header 信息，但它不起作用。

使用 postman ，效果很好。

所以无法理解为什么它不起作用!

谢谢

Answer 1

解决方案:

//Angular 服务:

const options = {} as any;

addProduct(productRequest: ProductRequest, selectedImages: File[]) {

        const formData =  new FormData();        

        for (let i = 0; i < selectedImages.length; i++) {
          formData.append('images', selectedImages[i]);
        }

        Object.keys(productRequest).forEach((key) => {formData.append(key, productRequest[key]); });

        return this.http.post<any>(baseUrl + '/addProduct', formData , options)
          .pipe(
            catchError(this.handleError)
          );
      }

//Spring REST 服务:

 @ApiOperation(value = "add product", response = Iterable.class)
    @ApiResponses(value = { @ApiResponse(code = 200, message = "Successfully added product") })
    @PostMapping("/addProduct")
    public void addProduct(@RequestPart(value = "images")       @ApiParam(value = "images")  MultipartFile[] images,
                           @RequestPart(value = "productName")  @ApiParam(value = "productName")  String productName,
                           @RequestPart(value = "description")  @ApiParam(value = "description")  String description,
                           @RequestPart(value = "realPrice")    @ApiParam(value = "realPrice")    String realPrice,
                           @RequestPart(value = "category")     @ApiParam(value = "category")     String category,
                           @RequestPart(value = "creator")      @ApiParam(value = "creator")      String creator,
                           @RequestPart(value = "tradeReference") @ApiParam(value = "tradeReference") String tradeReference
                 ) throws Exception {

        Product p = createProduct(productName, description, Double.valueOf(realPrice), category, creator, tradeReference);
        Arrays.asList(images)
                .stream()
                .forEach(image -> uploadImages(image, p));
        traderServices.addProduct(p);
    }

请注意，Product 对象被拆分为多个参数，以避免出现“不支持内容类型‘application/octet-stream’”和“不支持内容类型‘multipart/form-data’”等错误。将“realPrice”参数类型更改为 Double，生成“不支持内容类型“application/octet-stream””类型的异常，它适用于字符串。