fix: send images with correct content types

Gemfile

@@ -25,6 +25,9 @@ gem 'model-msearch'
 gem 'puma', '~> 5.0'
 gem 'sidekiq'
 
+# Other stuff
+gem 'marcel'
+
 # Windows does not include zoneinfo files, so bundle the tzinfo-data gem
 gem 'tzinfo-data', platforms: %i[ mingw mswin x64_mingw jruby ]
 

Gemfile.lock

@@ -306,6 +306,7 @@ DEPENDENCIES
   elasticsearch-model
   fancy_searchable!
   kaminari
+  marcel
   model-msearch
   pg (~> 1.1)
   puma (~> 5.0)

app/controllers/images_controller.rb

@@ -17,17 +17,23 @@ class ImagesController < ApplicationController
     hash = Digest::SHA256.hexdigest(url)
     path = Rails.root.join('public', 'cached-images', hash + ext)
     our_url = "/cached-images/#{hash}#{ext}"
+    content_type = nil
 
     if File.exist? path
-      redirect_to our_url
-      return
+      content_type = Marcel::MimeType.for Pathname.new(path)
+    else
+      content_type, body = fetch_image uri
+      File.binwrite path, body
     end
 
-    File.binwrite(
-      path,
-      Net::HTTP.get(parsed)
-    )
+    send_file path, disposition: :inline, content_type: content_type
+  end
 
-    redirect_to our_url
+  private
+
+  def fetch_image(uri)
+    response = Net::HTTP.get_response(uri)
+
+    [response['Content-Type'], response.body]
   end
 end