validation for schema (middlewares)

VALIDATELISTING IS SENT AS A MIDDLEWARE.

 const ValidateListing = (req, res, next) => {

 

  let { error } = listingSchema.validate(req.body);

  if (error) {

    let errMsg = error.details.map((el) => el.message).join(",");

    throw new ExpressError(400, errMsg);

  } else {

    next();

  }

};

app.post(

  "/listings",ValidateListing,

  wrapAsync(async (req, res, next) => {

   

    const newListing = new Listing(req.body.listing);

    await newListing.save();

    res.redirect("/listings");

  })

);app.put(

  "/listings/:id",ValidateListing,

  wrapAsync(async (req, res) => {

    if (!req.body.listing) {

      throw new ExpressError(400, "send valid data!");

    }

    let { id } = req.params;

    await Listing.findByIdAndUpdate(id, { ...req.body.listing });

    res.redirect(`/listings/${id}`);

  })

);