Beginnings of a FileController (serving the file upload feature)

app/controllers/file_controller.rb

@@ -0,0 +1,30 @@
+require 'application'
+class FileController < ApplicationController
+
+  layout 'default', :except => [:rss_feed, :rss_with_headlines, :tex,  :export_tex, :export_html]
+
+  def file
+    if have_file?(@params['id'])
+      render_text 'Download file' 
+    else 
+      render_text 'form'
+    end
+  end
+  
+  private
+  
+  def have_file?(file_name)
+    sanitize_file_name(file_name)
+    @wiki.storage_path
+  end
+
+  SANE_FILE_NAME = /[-_A-Za-z0-9]{1,255}/
+  def sanitize_file_name(file_name)
+    unless file_name =~ SANE_FILE_NAME
+      raise "Invalid file name: '#{file_name}'.\n" +
+            "Only latin characters, digits, underscores and dashes are accepted."
+    end
+  end
+
+end
+