Consider Sharability

[0Hughman0]

For notebooks relying on cassini to do things like fetch data, one certainly can't share this notebook with another user who doesn't have cassini installed.

In the case they do have cassini installed, unless things are configured identically between users, notebooks will not run correctly.

I think adding something like:

# smpl = project.env('WP1.1a')
smpl = project.share('WP1.1a')

I.e. to share you swap these lines over.

At that point I'm not completely sure what to do...

There needs to be some way of freezing the appropriate paths at the point project.share is called. For example adding metadata to the notebook file, which would probably be a mapping from children to relative paths.

[0Hughman0]

project.share looks very nice, but won't work because a sharee won't have a project.py.

Whatever we use, it should probably replace the project in the notebook. e.g.

from cassini import shareable_project

# from project import project

# smpl = project.env('WP1.1a')
smpl = shareable_project.env('WP1.1a')

Where shareable_project.env does something like:

def env(self, name):
    paths = check_existing() # checks if there's already paths in the metadata

    if not paths:
        from project import project  # avoids importing when no project
        paths = {}
        obj = project[name]
        paths[tuple()] = obj.folder
        for child in obj:
            paths[(child.name,)] = child.folder

        write_paths(paths)

    return TierProxy(paths)

Where TierProxy emulates access to paths such as smpl['DataSet'] and smpl / 'subfolder'.

It looks like adding metadata to a notebook might not actually be possible from within the notebook itself...

Could pickle, or separately json serialise TierProxy, but that would require sharer to also copy that object over.

[0Hughman0]

Would need to ensure magics like %hlts don't complain too much when in a shared context.

[0Hughman0]

It does look like adding metadata really can only be done outside of the notebook context - which maybe makes sense idk.

I think the server ContentsManager is kinda in charge of editing it.

We could add a share-notebook option in the file toolbar in JupyterLab?

We'd have to then use nbformat to edit the file and create a copy, which all seems a bit dodgy idk.

[0Hughman0]

I think describing what the aim here would be is good.

So with little modification it should be possible for a user to send a notebook for a Cassini project to another user who doesn't have the same project or possibly any project and for them to be able to run the code successfully. This includes loading data from other tiers and saving data.

I think it's reasonable for someone to require a user to install Cassini to run the notebook, but we shouldn't expect them to have to set it up.

When someone shares something like this, it's reasonable I think for us to expect them to copy and maybe zip up all the bits required.

Any paths would have to be switched to relative paths.

I'm not averse to something a bit crazy where to share, a user makes the = project.share('name') substitution, and then are forced to re-run every cell.

We can then create a directory, maybe called 'share-name', and every time a Cassini path to a file that exists is called, we create a copy with a relative path inside this directory.

This would require some sort of monkeypatchi g to enable capturing these paths and checking them, which is possible I think.