Rails passing additional params in some tag helpers

Question

Currently image_tag("file.jpg") produces normal image html tag, BUT src="file.jpg*?7485793246*" what the hell are those numbers anyway and how to disable them?

Answer 1

thats your development mode making sure that nothing gets cached so that if you change the image it actually gets to the browser. the production version won't have it.

Answer 2

Those are refered to as Asset Timestamps they can be used by the server to cache files. For example lets say you have a file called file.jpg on your server, you can set up your server to tell browsers like firefox to cache the file.jpg so the next time that browser visits your web-page it loads faster because file.jpg was already in memory.

The problem comes when you upload a new file.jpg because even though the image is different, your old users who have the image cached will still see the cached image, that is where asset timestamps come into play. Those numbers represent a timestamp of when the file was updated, so if you replace file.jpg?123456789 with file.jpg?987654321 then the user's browser will not use the cached version.

http://api.rubyonrails.org/classes/ActionView/Helpers/AssetTagHelper.html

long story short, it is only there to help you, and doesn't affect the way the file behaves at all. Users can still download the file and operating systems will see it as being a valid .jpg.

Answer 3

Solved, add this to environment.rb => ENV['RAILS_ASSET_ID'] = ''

Conclusion: yes, its a good rails stuff, but when you deal with ie6 and PNG images it can break your script. So be careful.