File Uploads

Handle file uploads in Ruby-based web applications, including streamlined storage on cloud services, the extraction of file metadata and handling of post-processing tasks like resizing and cropping of images

A long-lived project that still receives updates
Dragonfly is a framework that enables on-the-fly processing for any content type. It is especially suited to image handling. Its uses range from image thumbnails to standard attachments to on-demand text generation.
The project is in a healthy, maintained state
Shrine is a toolkit for file attachments in Ruby applications. It supports uploading, downloading, processing and deleting IO objects, backed by various storage engines. It uses efficient streaming for low memory usage. Shrine comes with a high-level interface for attaching uploaded files to database records, saving their location and metadata to a database column, and tying them to record's lifecycle. It natively supports background jobs and direct uploads for fully asynchronous user experience.
Repository is gone
No release in over 3 years
Fine Uploader by Andrew Valums integrated for Rails 3.1+ Asset Pipeline
No commit activity in last 3 years
No release in over 3 years
Attached is a Ruby on Rails cloud attachment and processor library inspired by Paperclip. Attached lets users push files to the cloud, then perform remote processing on the files.
No commit activity in last 3 years
No release in over 3 years
simple-image-uploader creates Image scaffold with file upload and removal. It is based on carrierwave and mini-imagegick gems. Image model, controller and form are have simple code that allows any application to use image upload immediately. Add simple-image-uploader gem to your Gemfile. Run bundle install. Then run 'rails g simple_image_uploader'. Run rails s and check http://localhost:3000/images.
Low commit activity in last 3 years
There's a lot of open issues
Treat an ActiveRecord model as a file attachment, storing its patch, size, content type, etc.