Add settings for Binder

[mgeier]

Sadly, this doesn't work yet.

There is an error when running ./dev-install.sh on Binder:

ValueError:                                                                                                           
"@jupyter-widgets/[email protected]" is not compatible with the current JupyterLab                             
Conflicting Dependencies:                                                                                             
JupyterLab                        Extension      Package                                                              
>=1.2.1 <1.3.0                    >=2.0.0-beta.1 <3.0.0@jupyterlab/application                                        
>=1.2.2 <1.3.0                    >=2.0.0-beta.1 <3.0.0@jupyterlab/notebook                                           
>=1.2.1 <1.3.0                    >=2.0.0-beta.1 <3.0.0@jupyterlab/rendermime                                         
>=1.5.0 <1.6.0                    >=2.0.0-beta.1 <3.0.0@jupyterlab/rendermime-interfaces                              
>=4.2.0 <4.3.0                    >=5.0.0-beta.1 <6.0.0@jupyterlab/services                                           

Apparently, the JupyterLab and jupyter-widgets/jupyterlab-manager versions have to match (see https://github.com/jupyter-widgets/ipywidgets/blob/master/packages/jupyterlab-manager/README.md), but I don't know how to handle this in a development installation ...

Any ideas?

See #2301.

[pbugnion]

Hmm... As far as I can tell, the classic notebook binder link works -- see my comment on issue #2301.

The JupyterLab instance that is created doesn't support widgets, though. I've opened a new issue to address this here. I think your PR could be adapted fairly easily to support this.

[jtpio]

Since the Binder is user facing, how about using a released version of ipywidgets instead?

This would mean adding ipywidgets=7.5 to environment.yml.

[mgeier]

You can create a Binder image for any given commit in the repo. I would expect each of those to have the appropriate version of ipywidgets and jupyter-widgets/jupyterlab-manager installed.

If all goes well (and I'm currently not sure that it will), I would like to do the same thing for the docs on RTD, which would mean that the latest docs are actually using the master version of the software.

And then, we could create Binder links on the RTD pages which link from a specific version of the docs to the exact same version running on Binder.

[jtpio]

OK, for this use case then it makes sense to do a dev install.

[jtpio]

For JupyterLab, specifying jupyterlab=1 in environment.yml should do the trick.

[mgeier]

Thanks @jtpio!

Now the above-mentioned error doesn't appear anymore, but the Binder build is hanging at some point.

This is the link I tried:
https://mybinder.org/v2/gh/mgeier/ipywidgets/binder-environment

I've kept the page open for more than an hour now and it's still not finished.

Any ideas what the problem could be?

[mgeier]

UPDATE: I've just started the Binder build again (and again), and after a few minutes it now gives me the original error.

[pbugnion]

Thanks for working on this!

I agree with @jtpio . I don't think we should do a dev-install for the public facing Binder link for ipywidgets.

I think the right way to make progress on improving Binder support is to include the JupyterLab manager and aim to close #2676.

[mgeier]

I agree with @jtpio . I don't think we should do a dev-install for the public facing Binder link for ipywidgets.

But it looks like @jtpio changed his mind, see #2659 (comment).

I think the right way to make progress on improving Binder support is to include the JupyterLab manager and aim to close #2676.

Sure. The question is only: which version of the JupyterLab manager?

I'm arguing that it should be the version corresponding to whatever commit is used in Binder.

What if you want to try out a new feature (probably from some feature branch, probably even from a fork) in Binder?
This won't work if the jupyter-widgets/jupyterlab-manager used by Binder is outdated (w.r.t the commit containing the new feature).

[jtpio]

Sorry @mgeier for the confusion. My comment was directed to the particular use case of being able to pin a Binder to a specific commit.

[jtpio]

By the way, is this PR still needed or replaced by #2701?

[mgeier]

Well I would prefer #2701, but if you prefer using conda, I could try to get this PR working as well.

But as soon as #2701 is merged, this PR becomes obsolete.