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How to Pass Data to a multer-gridfs-storage Middleware?
I am uploading some files to my MongoDB database but currently my upload.js middlware fileInfo object only accepts a single static bucket string since I cannot dynamically change the bucketName string. How can I pass the upload.js middeware any string I want for the bucketName?
ACTION:


export const uploadPhoto = (img) => (dispatch) => {
  const formData = new FormData();
  formData.append("file", img);
  const bucketName = "photos"; //HOW DO USE THIS BUCKET NAME IN THE upload.js Middlware?
  axios
    .post("/video/upload", formData)
    .then((res) => {})
    .catch((err) => {
      console.log(err);
    });
};



ROUTES:


const router = require("express").Router();
var mongoose = require("mongoose");
var Schema = mongoose.Schema;
var ObjectId = require("mongodb").ObjectId;
const { authUser } = require("../middleware/auth");
const uploadMulter = require("../middleware/upload");


//HOW DO I PASS DATA TO THE uploadMulter Middleware?
router.post("/upload", authUser, uploadMulter, (req, res) => {
  console.log(req.file);
});



Upload Middleware:


const path = require("path");
var mongoose = require("mongoose");
const crypto = require("crypto");
const multer = require("multer");
const { GridFsStorage } = require("multer-gridfs-storage");
const db = require("../config/.env").mongoURI;

const storage = new GridFsStorage({
  url: db,
  file: (req, file) => {
    return new Promise((resolve, reject) => {
      crypto.randomBytes(16, (err, buf) => {
        if (err) {
          return reject(err);
        }
        const filename = buf.toString("hex") + path.extname(file.originalname);
        const fileInfo = {
          filename: filename,
          bucketName: "HOW DO I CHANGE THE BUCKETNAME?", //<--?
          metadata: {
            author: req.user._id,
          },
        };
        resolve(fileInfo);
      });
    });
  },
});

const upload = multer({ storage });

module.exports = upload.single("file");




I used the params from the URL, but I'm sure there's a better solution.
ACTION:


export const uploadPhoto = (img, bucketName) => (dispatch) => {
  const formData = new FormData();
  formData.append("file", img);
  axios
    .post(`/video/upload/${bucketName}`, formData)
    .then((res) => {})
    .catch((err) => {
      console.log(err);
    });
};



ROUTES:


const router = require("express").Router();
var mongoose = require("mongoose");
var Schema = mongoose.Schema;
var ObjectId = require("mongodb").ObjectId;
const { authUser } = require("../middleware/auth");
const uploadMulter = require("../middleware/upload");


router.post("/upload/*", authUser, uploadMulter, (req, res) => {
  console.log(req.file);
});



Upload Middleware:


const path = require("path");
var mongoose = require("mongoose");
const crypto = require("crypto");
const multer = require("multer");
const { GridFsStorage } = require("multer-gridfs-storage");
const db = require("../config/.env").mongoURI;

const storage = new GridFsStorage({
  url: db,
  file: (req, file) => {
    return new Promise((resolve, reject) => {
      crypto.randomBytes(16, (err, buf) => {
        if (err) {
          return reject(err);
        }
        const filename = buf.toString("hex") + path.extname(file.originalname);
        const fileInfo = {
          filename: filename,
          bucketName: req.params[0], //Heres my solution, but its not the best.
          metadata: {
            author: req.user._id,
          },
        };
        resolve(fileInfo);
      });
    });
  },
});

const upload = multer({ storage });

module.exports = upload.single("file");




You can also pass data through headers, but im pretty sure thats it.
