codesnips

file-upload

javascript 
const multer = require('multer');

const ALLOWED_MIME = new Set(['image/jpeg', 'image/png', 'image/webp']);

function fileFilter(req, file, cb) {
  if (!ALLOWED_MIME.has(file.mimetype)) {

Upload and Resize User Avatars with Multer and Sharp in Express

express multer sharp
by codesnips 3 tabs
go 
package upload

import (
	"errors"
	"io"
	"log"

Streaming Multipart File Uploads to Disk in Go net/http

go net-http multipart
by codesnips 3 tabs
ruby 
class AttachmentContentTypeValidator < ActiveModel::EachValidator
  SIGNATURES = {
    "image/png"       => ["\x89PNG\r\n\x1a\n".b],
    "image/jpeg"      => ["\xFF\xD8\xFF".b],
    "image/gif"       => ["GIF87a".b, "GIF89a".b],
    "application/pdf" => ["%PDF-".b]

Safer File Attachments: Content Type + Size Validation

rails security active-storage
by codesnips 4 tabs