发送收到 spring FilePart 而不保存

Question

我需要使用 WebClient 将 RestController 中收到的 FilePart 发送到 API，我该怎么做？

找到一个示例，将图像保存到磁盘。

private static String UPLOAD_ROOT = "C:\pics\";

public Mono<Void> checkInTest(@RequestPart("photo") Flux<FilePart> photoParts,
                              @RequestPart("data") CheckInParams params, Principal principal) {
    return saveFileToDisk(photoParts);
}

private Mono<Void> saveFileToDisk(Flux<FilePart> parts) {
    return parts
            .log("createImage-files")
            .flatMap(file -> {
                Mono<Void> copyFile = Mono.just(Paths.get(UPLOAD_ROOT, file.filename()).toFile())
                        .log("createImage-picktarget")
                        .map(destFile -> {
                            try {
                                destFile.createNewFile();
                                return destFile;
                            } catch (IOException e) {
                                throw new RuntimeException(e);
                            }
                        })
                        .log("createImage-newfile")
                        .flatMap(file::transferTo)
                        .log("createImage-copy");

                return Mono.when(copyFile)
                        .log("createImage-when");
            })
            .log("createImage-flatMap")
            .then()
            .log("createImage-done");
}

然后再次阅读并发送到另一个服务器

.map(destFile -> {
        MultiValueMap<String, Object> map = new LinkedMultiValueMap<>();
        try {
            map.set("multipartFile", new ByteArrayResource(FileUtils.readFileToByteArray(destFile)));
        } catch (IOException ignored) {
        }
        map.set("fileName", "test.txt");
        WebClient client = WebClient.builder().baseUrl("http://localhost:8080").build();

        return client.post()
                .uri("/upload")
                .contentType(MediaType.MULTIPART_FORM_DATA)
                .syncBody(map)
                .exchange(); //todo handle errors???
    }).then()

有没有办法避免保存文件？

Answer 1

我会提到@Abhinaba Chakraborty 的解决方案

中提供

Probably something like this:

  @PostMapping(value = "/images/upload", consumes = MediaType.MULTIPART_FORM_DATA_VALUE)
  public Mono<ResponseEntity<Void>> uploadImages(@RequestPart("files") Flux<FilePart> fileParts) {
    return fileParts
        .flatMap(filePart -> {
          return webClient.post()
              .uri("/someOtherService")
              .body(BodyInserters.fromPublisher(filePart.content(), DataBuffer.class))
              .exchange()
              .flatMap(clientResponse -> {
                //some logging
                return Mono.empty();
              });
        })
        .collectList()
        .flatMap(response -> Mono.just(ResponseEntity.accepted().build()));
  }

This accepts MULTIPART FORM DATA where you can attach multiple image files and upload them to another service.

发送收到 spring FilePart 而不保存

Send received spring FilePart without saving

java

spring

spring-webflux