You can now upload apps that need a licence key in a file on the purchaser’s computer to work. This can help you determine if the user purchased this copy of the app, or if they just downloaded it elsewhere.
Once you’ve enabled licence keys, Ubuntu Software Centre will fetch a licence key when it completes a purchase, and copy that into the right file for your app to check. It is up to you, the developer, to provide keys that are hard to guess, check if the key is there when your application starts and behave accordingly.
You will receive a notification by email when the number of available licence keys goes below a certain configurable threshold, and you will see notices when you visit the website telling you about this also. If we run out of license keys we will necessarily stop selling copies of your app.
To enable licence keys for your app you need to provide two things:
- A set of licence keys. These will be provisioned to users, one per subscription together with the downloaded package.
- A path to the file where your app will expect to find the licence key. This should be entered as a path relative to the installed binary, or alternatively a path within the user’s home folder, beginning with '~'. For example, 'data/license.txt' will place the key under /opt/
/data/license.txt and '~/myapp_license.txt' will place the license in the user’s home folder