如何使用Retrofit2上传图片并保存到NodeJS服务器？

implementation 'com.squareup.retrofit2:retrofit:2.x.x'
implementation 'com.squareup.retrofit2:converter-gson:2.x.x'

public interface ApiService {
    @Multipart
    @POST("upload")
    Call<ResponseBody> uploadImage(@Part MultipartBody.Part image);
}

// 创建Retrofit实例
Retrofit retrofit = new Retrofit.Builder()
        .baseUrl("http://your-nodejs-server-url/")
        .addConverterFactory(GsonConverterFactory.create())
        .build();

// 创建API服务实例
ApiService apiService = retrofit.create(ApiService.class);

// 创建文件对象
File file = new File("path/to/your/image.jpg");

// 创建请求体
RequestBody requestBody = RequestBody.create(MediaType.parse("image/*"), file);
MultipartBody.Part imagePart = MultipartBody.Part.createFormData("image", file.getName(), requestBody);

// 调用上传图片的方法
Call<ResponseBody> call = apiService.uploadImage(imagePart);
call.enqueue(new Callback<ResponseBody>() {
    @Override
    public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {
        // 上传成功处理
    }

    @Override
    public void onFailure(Call<ResponseBody> call, Throwable t) {
        // 上传失败处理
    }
});

const express = require('express');
const multer = require('multer');

const app = express();
const upload = multer({ dest: 'uploads/' });

app.post('/upload', upload.single('image'), (req, res) => {
  // 保存上传的图片到指定目录
  // 可以使用req.file来访问上传的文件信息
  res.send('Image uploaded successfully');
});

app.listen(3000, () => {
  console.log('Server started on port 3000');
});