[xwiki-devs] Temp files for images with width param grow until JVM exit

Hi there, I was testing out the XWiki Enterprise 3.5 release and I noticed that the temporary files folder under my Tomcat 7 kept growing while I was testing out XWiki. I had added a number of jpg attachments to a page that was using the {{photoalbum}} macro to display them. However, I found that this causes a number of download requests with the width parameter set, which seems to cause a new temporary file to be created for each request. It seems that even though the original image is cached it re-creates a new XWikiAttachmentContent thumbnail from those original bytes each time, causing multiple DiskFileItems to be created. Looking through the code for XWikiAttachmentContent it does set the deleteOnExit() for the DiskFileItem's store location file, but this file then will only be deleted when the JVM is shutdown. If multiple pages have many images each and they are being displayed in the photoalbum macro, then this creates a problem with diskspace being used up until the server is restarted. (And in my case for some reason stopping Tomcat via the service icon terminates the JVM in a way that doesn't cause the deleteOnExit() to be called as all of the temporary files are left behind after Tomcat is stopped) How can we stop all these temporary files from becoming a problem with a long running web application? There may be a better way, but I tried hacking around with the 3.5 platform on my github account and created a component to fix the problem by deleting files that had their DiskFileItem no longer being referenced: Modified 3.5 platform (mainly XWikiAttachmentContent) https://github.com/jamiemaher/xwiki-platform/tree/feature-tempfiles-3.5 Temporary Files provider component referenced by the XWikiAttachmentContent: https://github.com/jamiemaher/xwiki-tempfiles-component It seems to work pretty well, although there seem to be some files that don't seem to be reclaimed, although I haven't tracked down if it's because they are also in the regular xwiki cache as well. Thanks, Jamie