Requirements for the system

[JuhaS]

Technologies

• Python
• Cron or long-running service
• libcloud to interact with cloud provider api's. Specifically this method to fetch all images for a provider.

Goal for the system System will regularly check for most up-to date image-id's for various cloud providers (start with digitalocean) and detect when an image-id has changed.

Detailed requirements:

There will be one python process that will either be run through cron or as long-running daemon (should never crash in this case).

Configuration will be read from json or yaml file. This will include set of cloud providers (digitalocean to start with) and image-names or regex pattern for each provider (We use Ubuntu 14.04 64bit).

Process should fetch the list of images for each provider, find the target-images and compare them to the previous values. Action is then triggered with the result (this action can be to just write it to a file for now).

[jsundmannorberg]

I prefer the cron-based approach. My idea is to run a script every x minutes that downloads image-id's for all specified providers and writes the information together with the image names to a JSON file, which will be used next time the script is executed for comparison. If something has changed (images added, deleted, modified), an action is triggered.

[jsundmannorberg]

Currently the diff is written to a JSON file with a timestamped filename and placed in a directory specified in config.json if a change is detected.