[Tarsnap GUI] RFC: Automatic job backup and more

[Shinnok <admin@shinnok.com>]

Hi list,

Now that the first release is done, I'm already hard at work towards the next version, v0.6. This point release will include adjustments and improvements based on user feedback that I received so far and also a couple new features. One example of a new feature would be task canceling(the ability to abort all currently executing tarsnap tasks). The other is automatic backups.

Automatic backups are important, since right now, every action is achieved manually; the user has to open the application and initiate backups by hand, this is especially pertinent to Jobs. A simple solution for this, that I've been holding on to for a while, would be automatic Job backup via a --cron option added to the Tarsnap frontend application. I already added support for command line args in regards to another issue and the design of the application allows, with minimal changes, to execute any Tarsnap operation without popping up any UI. 

So what I propose is:

1. Adding an extra Job specific option, a checkbox, "Include in automatic backups";
2. Add --cron option to the application. Upon firing up with that parameter, Tarsnap will execute headless and initiate job backup on all jobs that have the previous option checked, in a sequential manner.
3. The user proceeds to create a scheduled invocation of "tarsnap-gui --cron" with his scheduler(system or something else) of choice and at his own preference of interval and cadence.

I'd be the first user of that. I like the simplicity of it and the fact that I don't need an extra daemon to "watch" over stuff for me.

Specific questions:

1. Does this sound useful for anyone else besides me?
2. Should I name the parameter --cron differently, maybe something more inviting like --run-jobs or --scheduler?
3. Regarding feedback from the automatic backups(failure, insights), for now the application will print everything to stdout and the user is free to redirect it to his log file of choice. But for the future and given that Tarsnap is a sexy desktop application I might add:
    a) System tray/menubar popup notifications (completion, failure, extra info)
    b) The ability to open the application to view more details from the said notifications
    c) Persistent Backup log (this is part of another Idea feature)

On a different note,

I have another change that I want to make but first I'd like to probe it against this list:

I'd like to change the default directory for newly generated keys(via the Setup Wizard for now) from the system specific APPDATA ones, which currently are:
1. ~/.local/share/ on Linux/BSD
2. ~/Library/Application Support/ on OS X

To just ~/Documents. The reasoning behind it is that we shouldn't hide the keys in such obscure places since they are not transient nor expendable, whereas the application's data is. We also invite the user to keep the key safe(on wizard complete), but then provide a path that he's most likely to ignore in first instance and then completely forget about it. Another aspect to consider is that a user should be a bit more careful with stuff residing Documents, rather than some obscure hidden system paths. Think backups, system restore or system reset.

Regards,
Shinnok