import axios from "axios";
import FormData from "form-data";

// create DL stream
const dl = await axios.get('url.tar', {
  responseType: "stream",
});

// create multipart 
const formData = new FormData();
formData.append('file', dl.data);

// directly proxy the stream to the upstream
const up = await axios({
  method: 'POST',
  url: `upstream-url/api/post/add`,
  data: formData,
  maxContentLength: Infinity
});

console.log(up.data)