Ruby File Upload

Ruby ships with everything you need to upload a file to files.link: the net/http standard library handles JSON requests and raw binary PUTs without installing a single gem. That matters when you are running inside a slim container, a Lambda layer, or a CLI tool where every dependency you add to the Gemfile is weight you carry forever. The aws-sdk-s3 gem pulls in aws-sdk-core, aws-sigv4, jmespath and a chain of transitive dependencies just to sign a request; files.link replaces all of that with three plain HTTP calls.

The flow is identical across every Ruby HTTP client. Step one, POST your file metadata (name, size, type) to POST /v1/files/{folderId} with the raw API key in the Authorization header — no Bearer prefix. The response is { success: true, urls: [{ url, id, ... }] }, where url is a short-lived presigned PUT target. Step two, PUT the raw file bytes to that url. Step three, POST { ids: [id] } to /v1/files/confirm-upload to finalize the object and make its CDN link live.

With stdlib net/http it looks like this:

require 'net/http'
require 'json'

KEY = ENV.fetch('FILESLINK_KEY')
BASE = 'https://api.files.link'

def upload(folder_id, path)
  meta = { filesMetadata: [{ name: File.basename(path), size: File.size(path), type: 'image/png' }] }
  res = Net::HTTP.post(URI("#{BASE}/v1/files/#{folder_id}"),
        meta.to_json, 'Authorization' => KEY, 'Content-Type' => 'application/json')
  slot = JSON.parse(res.body)['urls'].first

  put = Net::HTTP.new(URI(slot['url']).host, 443); put.use_ssl = true
  put.send_request('PUT', URI(slot['url']).request_uri, File.binread(path), 'Content-Type' => 'image/png')

  Net::HTTP.post(URI("#{BASE}/v1/files/confirm-upload"),
        { ids: [slot['id']] }.to_json, 'Authorization' => KEY, 'Content-Type' => 'application/json')
  slot['id']
end

In a Rails app the same three calls drop cleanly into an ActiveJob or Sidekiq worker, so a controller can accept the upload, enqueue the transfer, and return immediately instead of blocking the request on a slow PUT. Because net/http is part of the standard library, this also runs unchanged in a bare Ruby script, a Sinatra endpoint, or a Jekyll build hook without touching the Gemfile.

Prefer HTTParty or Faraday? The same three calls map one-to-one — only the syntax changes. files.link returns a public CDN URL or a signed URL per file, so you decide visibility per object rather than per bucket. Storage is encrypted at rest and billed against prepaid credits, so a runaway upload script can never produce a five-figure surprise invoice.