How to proxy multiple file upload using NodeJs?

Question

Ok, so i need to proxy file array upload from my express node app, to remote PHP Api.

Ideally i would use something close to Nginx proxy since it has same modules with node.

If not,i would emulate form resend.

Can you help find the best way for doing this?

Answer 1

So, i did not found execaly how to proxy request itself, as it would do nginx, but at least i figured out how to redirect request with all it's data to different source.

So, here we use express-fileupload to get our file data from req, and form-data to create a form and send data.

import app from '@app';
import { authMw as checkJwtAndAddToRequest } from '@middleware/Auth';
import { Router } from 'express';

import fileupload, { UploadedFile } from "express-fileupload";

import FormData from 'form-data';

//add this MW to add files to you'r req

app.use(checkJwtAndAddToRequest)
app.use(fileupload());

app.post('/upload', (req, res) => {
    const uploadableFiles: UploadedFile[] | UploadedFile | undefined = req.files?.formFieldName;

    if(!uploadableFiles) {
        throw Error('Pls add files to upload them');
    }

    //Transorm single file to same form as an array of files
    const files: UploadedFile[] = Array.isArray(uploadableFiles) ? uploadableFiles : Array<UploadedFile>(uploadableFiles);

    //create form
    const form = new FormData();

    //add files
    files.forEach(
        file => form.append('files[]', file.data.toString(), file.name)
    )

    //Submit 
    form.submit({
        protocol: 'http:',
        host: process.env.API_URL,
        path: '/api-path-for/file/upload',
        method: 'POST',
        headers: {
            //Add auth token if needed
            authorization: `Bearer ${String(req.body.jwtToken)}`
        }
    }, (err, response) => {
        if(err) {
            //handle error 
            res.status(503).send('File server is currently unavailable');
        }
        //return remote response to original client
        response.pipe(res)
    });
});