Cms image cache

app/models/cms/attachment.rb

@@ -17,7 +17,7 @@ class Attachment < ActiveRecord::Base
     before_validation :set_cardinality
     before_save :set_section, :sanitized_file_path_and_name
     before_create :setup_attachment
-
+    after_save :clear_cached_files
     belongs_to :attachable, :polymorphic => true
 
     include DefaultAccessible
@@ -269,5 +269,20 @@ def dirty!
       # Seems like a hack, is there a better way?
       self.updated_at = Time.now
     end
+
+    #ensure all versions of this file are cleared from cache
+    def clear_cached_files
+      if Rails.configuration.cms.attachments.file_cache_directory
+        versions.each do |file|
+          #make sure data_file_path does not start with any ../ since this is user generated
+          sanitized_path=file.data_file_path.gsub(/\A(\.{2}\/)*/, '')
+          path = File.join(Rails.configuration.cms.attachments.file_cache_directory, file.data_file_path)
+          if File.exists?(path)
+            FileUtils.rm(path)
+          end
+        end
+      end
+    end
+
   end
 end

lib/cms/attachments/attachment_serving.rb

@@ -32,7 +32,12 @@ def self.send_attachments_with
     end
 
     class FilesystemStrategy
-
+
+      def self.file_cache_directory
+        Rails.configuration.cms.attachments.file_cache_directory
+      end
+
+
       def self.attachments_storage_location
         Rails.configuration.cms.attachments.storage_directory
       end
@@ -42,6 +47,7 @@ def self.send_attachment(attachment, controller)
         style = "original" unless style
         path_to_file = attachment.path(style)
         if File.exists?(path_to_file)
+          copy_file_to_cache(path_to_file, attachment.data_file_path)
           Rails.logger.debug "Sending file #{path_to_file}"
           controller.send_file(path_to_file,
                                :filename => attachment.file_name,
@@ -54,6 +60,20 @@ def self.send_attachment(attachment, controller)
           raise ActiveRecord::RecordNotFound.new(msg)
         end
       end
+
+      def self.copy_file_to_cache(file_path, cache_path)
+        if file_cache_directory
+          cache_path = File.join(file_cache_directory, cache_path)
+          #remove the filename so we can do a mkdir -p
+          unless File.exists?(cache_path)
+            dir_path = cache_path.split("/")[1..-2].join("/")
+            FileUtils.mkdir_p(File.join("/", dir_path))
+            FileUtils.cp(file_path, cache_path)
+            FileUtils.chmod(0644, cache_path)
+          end  
+        end
+      end
+
     end
   end
 end