OkHttp上傳文件，服務器端請求解析找不到文件信息的問題

長話短說，不深刻解釋了，官方給的上傳案例代碼：

 

private static final String IMGUR_CLIENT_ID = "...";
  private static final MediaType MEDIA_TYPE_PNG = MediaType.parse("image/png");

  private final OkHttpClient client = new OkHttpClient();

  public void run() throws Exception {
    // Use the imgur image upload API as documented at https://api.imgur.com/endpoints/image
    RequestBody requestBody = new MultipartBuilder()
        .type(MultipartBuilder.FORM)
        .addPart(
            Headers.of("Content-Disposition", "form-data; name=\"title\""),
            RequestBody.create(null, "Square Logo"))
        .addPart(
            Headers.of("Content-Disposition", "form-data; name=\"image\""),
            RequestBody.create(MEDIA_TYPE_PNG, new File("website/static/logo-square.png")))
        .build();

    Request request = new Request.Builder()
        .header("Authorization", "Client-ID " + IMGUR_CLIENT_ID)
        .url("https://api.imgur.com/3/image")
        .post(requestBody)
        .build();

    Response response = client.newCall(request).execute();
    if (!response.isSuccessful()) throw new IOException("Unexpected code " + response);

    System.out.println(response.body().string());
  }

上面這個代碼上傳文件在Java服務器端用spring boot的 MultiPart解析不到上傳的文件，用Python Django，問題亦然。

找到了一個泡網同窗的代碼：

作了改動1：

 

RequestBody requestBody = new MultipartBuilder()
                .type(MultipartBuilder.FORM)
                .addPart(
                        Headers.of("Content-Disposition", "form-data; name=\"UserId\""),
                        RequestBody.create(null, UserId))
                .addPart(
                        Headers.of("Content-Disposition", "form-data; name=\"SecurityCode\""),
                        RequestBody.create(null, SecurityCode))
                .addPart(
                        Headers.of("Content-Disposition", "form-data; name=\"File\"; filename =\"avatar_upload.jpg\""),
                        RequestBody.create(MediaType.parse("image/jpeg"), file))


                .build();

改成以上代碼後，Django請求解析能夠找到文件了，Spring boot的multipart任然找不到文件信息。

改動1的改動點是：文件的Header信息裏面必須有上傳文件的名字，固然這個名字實際上是隨便起的，通常後綴保持正確便可。

這個時候不得再也不參考泡網同窗的代碼，作了修改2：

 

RequestBody requestBody = new MultipartBuilder()
                .type(MultipartBuilder.FORM)
                .addPart(
                        Headers.of("Content-Disposition", "form-data; name=\"UserId\""),
                        RequestBody.create(null, UserId))
                .addPart(
                        Headers.of("Content-Disposition", "form-data; name=\"SecurityCode\""),
                        RequestBody.create(null, SecurityCode))
                .addPart(
                        Headers.of("Content-Disposition", "form-data; name=\"File\"; filename =\"avatar_upload.jpg\""),
                        RequestBody.create(MediaType.parse("application/octet-stream"), file))

                .build();

 這回Spring Boot multipart 依舊找不到文件信息了，這回的改動點是把mime類型由圖片類型"image/jpeg"改爲了附件類型：

"application/octet-stream"

 

 最後借鑑StackOverFlow的某貼的代碼：http://stackoverflow.com/questions/30707681/multipart-file-upload-with-okhttp-spring，

 

RequestBody body = new MultipartBuilder()
    .addFormDataPart("qqfile", filename, RequestBody.create(MediaType.parse("media/type"), new File(filename)))
    .type(MultipartBuilder.FORM)
    .build();

Request request = new Request.Builder()
    .url("/path/to/your/upload")
    .post(body)
    .build();

OkHttpClient client = new OkHttpClient();
Response response = client.newCall(request).execute();

由於這個帖子的topic就是解決Spring MultiPart的問題，最後終於能夠上傳了，修改點在於完全修改了添加文件使用的函數接口，我在build gradle裏面已經準備用Apache HttpClient了。

 

OkHttp有點坑爹啊。

 

 

參考：

https://github.com/square/okhttp/wiki/Recipes

http://www.jcodecraeer.com/a/anzhuokaifa/androidkaifa/2015/0824/3355.html