Question/Request: Directory for data that should persist over updates.

[Mark Shuttleworth]

On 28/01/16 05:44, Lefteris Karapetsas wrote:
> Some snaps, including mine need to store some data, a database let's say,
> or in my case a whole blockchain. So far I was instructed to do that at
> $SNAP_APP_DATA_PATH. This works fine for now but whenever the user updates
> the snap from what I understand this whole directory will be copied into
> the next version's directory, to enable the transaction updating and
> rollback nature of Snappy Ubuntu.
>
> This is not going to work for my snap and I need to ask if there is any
> directory where I can store data for the application that will persist over
> any update.

Hi Lefteris

The intention is that the data copy is invisible to the snap (the apps /
services are shut down, the data copied, and then the new version
started). Can you go into more detail about why that won't work in your
case? Is it a question of the size of the data?

Mark