post-link actions are missing but required (by upstream)

[marscher]

similar to widgetsnbextension, which installs and registers the javascript parts of the widgets in the local installation, we need to this for this package as well. in #3 someone stated that is is sufficient to only depend on widgetsnbextension for this purpose, but this does not hold true (any more).
https://github.com/conda-forge/widgetsnbextension-feedstock/blob/master/recipe/post-link.sh

People are getting problems with widgets because they are not installed fully (eg. installed python pkg, javascript extension installed and registered).

cc conda-forge/nglview-feedstock#5

[marscher]

Note that even the maintainers of ipywidgets relied on this fact: https://github.com/jupyter-widgets/ipywidgets#install

[marscher]

cc @gph82

[jasongrout]

The issue you link above is a problem in the nglview feedstock, not this one. The nglview feedstock should not be a noarch feedstock.

[hainm]

@jasongrout ideally we should not need to do the post-install. I am not convinced to require user to do that. Hopefully notebook folks can have better solution.

[jakirkham]

Chiming in here as well to say @jasongrout is correct. nglview cannot be noarch: python if it needs post-link scripts. Please fix that issue first and see if the problem doesn’t go away.

If you are wanting to use noarch: python with post-link scripts, that should be a conda/conda-build enhancement request not a feedstock issue.

[jasongrout]

@jasongrout ideally we should not need to do the post-install. I am not convinced to require user to do that. Hopefully notebook folks can have better solution.

Agreed (we've all suffered because of this), but that's how the current notebook extension system works. The conversation about a better notebook extension system is over at jupyter/notebook#1706.

[jasongrout]

Let's move the discussion about getting nglview working over to conda-forge/nglview-feedstock#5, and the discussion about the notebook extension system (especially if someone wants to work on it!) over to jupyter/notebook#1706.

[jasongrout]

Just to be clear for @marscher - no change is needed to this ipywidgets feedstock. The thing that broke the nglview installation was moving it to a noarch package, since noarch packages do not execute post-link scripts. And as @jakirkham pointed out, getting noarch packages to work with post-install scripts is a feature request for conda/conda-build.

[marscher]

I have retested with a local build without noarch and still there are no enabled notebook extensions available (py27, will redo with py36). Have you taken a look at the official documentation? The devs there are requiring conda-forge to handle the extensions activation, which is currently not the case.

[maartenbreddels]

Hi @marscher
these are the devs :)
ipywidget does not have the post script to enable the extension, that needs to happen for the widgetsnbextension, which you can find here:
https://github.com/conda-forge/widgetsnbextension-feedstock/tree/master/recipe

[marscher]

Hi Maarten, then I wonder why their extensions are not enabled. But I should report there I'd guess. Best, Martin

[maartenbreddels]

Try with a new conda env, if you install for instance bqplot or ipyvolume (from conda forge), you should see widgetsnbextensions being installed, and enabled if you do jupyter nbextension list.
Note that if you install it from anaconda's main channel, it will not enable (they have a policy of not running post scripts)

[marscher]

thanks, will do so.

[jasongrout]

@maartenbreddels brings up a good point about channels - our conversation here is about the conda-forge widgetsnbextension, which we maintain. The defaults channel widgetsnbextension package does things a different way. Make sure you're installing the conda-forge channel version for our conversation here.

[marscher]

I wrongly named the post/prelink scripts in the nglview feedstock. But even with nglview extension enabled properly the widgets do not show up. It is for sure not an upstream problem. Sorry for causing so much noise!

[jasongrout]

I wrongly named the post/prelink scripts in the nglview feedstock.

Ah, that would do it too.