Snap package

[jwallden]

This is work to build Nebula as a snap package with reference to #172
This snap is already published on https://snapcraft.io/nebula and if there is interest I'm happy to transfer ownership of that to the Nebula project

[CLAassistant]

All committers have signed the CLA.

[jwallden]

Oh, and the files are available in https://github.com/jwallden/nebula-snap/
I put the README in snap/local for this pull request.

[toonsevrin]

Hooray! Also solves #101 (partially)

[toonsevrin]

One more thing! Perhaps it would be nice to add the following to the Readme:

Install without any confinement

To load configs from other locations you need to remove the confinement. Run the following command to install Nebula without restrictions:

sudo snap install nebula --devmode

[jwallden]

Good idea. I'll add it.

[toonsevrin]

Dang, I keep bugging you here but is there any reason why you are using SNAP_COMMON instead of SNAP_USER_COMMON? The latter would allow you to run without sudo I think! 🎉

[jwallden]

It's fine! Glad to have the conversation.

The SNAP_USER_COMMON is not restored on a snap refresh. This means, at least as I understand it, that e g the keys and config used in Nebula would get deleted when the package is updated.
See here: https://snapcraft.io/docs/environment-variables

However, when I look at it now it seems that SNAP_COMMON is also not backed up and restored. So actually I'm not sure why I chose SNAP_USER_COMMON. It is a while since I did this but from what I recall, back when I tested things SNAP_COMMON seemed lik a better option.

Now, In the big scheme of things I'm not really sure that it would matter with regards to running it with sudo. I think that since we're using network-control sudo would be required anyway.

[toonsevrin]

@jwallden :)) what the documentation says about both SNAP_COMMON and SNAP_USER_COMMON is that the data is shared accross all versions of your snap. This means if you upgrade or downgrade, you actually retain your data, while with SNAP_DATA, it is lost. There you go!

And true, all though all the side-utilities (signing, keygen...) would work without sudo, which is somewhat nice.

[shaunburch]

Beat me to it :), is this still under consideration?

[jwallden]

Unclear if it's considered actively or not. I haven't got any reaction from Nebula mainainers whatsoever :)