A simple tool to see when other services/clients like Gmail open an image and test if they are storing it within their cache.

Feel free to use this as a demo or in actual testing.

Image link (replace slug with anything): http://cache-logger.herokuapp.com/change-me-to-anything

To check the logs without opening the image, append a /log to the end: http://cache-logger.herokuapp.com/change-me-to-anything/log

You can also do /destroy to delete all logs from an image and /remove to delete the last log, but will have to make those calls using curl:

curl -X DELETE http://cache-logger.herokuapp.com/change-me-to-anything/destroy
curl -X DELETE http://cache-logger.herokuapp.com/change-me-to-anything/remove

Assuming you have git, ruby, bundler, and heroku setup... you can simply do:

git clone https://github.com/kale/image-cache-logger
cd image-cache-logger
bundle install
heroku create
git push heroku master

Copyright (c) 2013 Kale Davis

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.