1 files changed, 55 insertions, 0 deletions
diff --git a/lib/paperclip/response_with_limit_adapter.rb b/lib/paperclip/response_with_limit_adapter.rb
new file mode 100644
index 000000000..7d897b8d6
--- /dev/null
+++ b/lib/paperclip/response_with_limit_adapter.rb
@@ -0,0 +1,55 @@
+# frozen_string_literal: true
+
+module Paperclip
+  class ResponseWithLimitAdapter < AbstractAdapter
+    def self.register
+      Paperclip.io_adapters.register self do |target|
+        target.is_a?(ResponseWithLimit)
+      end
+    end
+
+    def initialize(target, options = {})
+      super
+      cache_current_values
+    end
+
+    private
+
+    def cache_current_values
+      @original_filename = filename_from_content_disposition || filename_from_path || 'data'
+      @size = @target.response.content_length
+      @tempfile = copy_to_tempfile(@target)
+      @content_type = @target.response.mime_type || ContentTypeDetector.new(@tempfile.path).detect
+    end
+
+    def copy_to_tempfile(source)
+      bytes_read = 0
+
+      source.response.body.each do |chunk|
+        bytes_read += chunk.bytesize
+
+        destination.write(chunk)
+        chunk.clear
+
+        raise Mastodon::LengthValidationError if bytes_read > source.limit
+      end
+
+      destination.rewind
+      destination
+    rescue Mastodon::LengthValidationError
+      destination.close(true)
+      raise
+    ensure
+      source.response.connection.close
+    end
+
+    def filename_from_content_disposition
+      disposition = @target.response.headers['content-disposition']
+      disposition&.match(/filename="([^"]*)"/)&.captures&.first
+    end
+
+    def filename_from_path
+      @target.response.uri.path.split('/').last
+    end
+  end
+end