Error: only one instance of babel-polyfill is allowed

[mrakitin]

We together with @yxqd are trying to implement tomvizweb visualization in Jupyter notebooks (please see https://github.com/scikit-beam/ipywe). We met a problem when attempting to visualize two objects:

Steps to reproduce:

• Prepare the environment:

  $ git clone https://github.com/scikit-beam/ipywe
  $ cd ipywe
  $ conda create -n ipywe python=3
  $ source activate ipywe
  $ ./dev_js_update.sh
  # Start Jupyter:
  $ jupyter notebook --port=8000

• Open http://localhost:8000/notebooks/tests/test_tomvizjs.ipynb and run all cells.
• Run the cell ipywe.tomvizjs.TomvizJs(url='https://openchemistry.github.io/tomvizweb/data/GeometryContourExploration.tomviz') one more time.
• Check browser console log.

I hope it can be fixed soon. We don't observe problems with vtk.js visualization of multiple objects in different cells (try http://localhost:8000/notebooks/tests/test_vtkjs.ipynb).

[cryos]

@jourdain do you have any ideas on what is wrong here?

[jourdain]

Yes, I've added the polyfill inside tomviz-web to make it work on "old" browsers.

But when inside the notebook, Jupyter already provide the polyfill, so by loading tomviz-web we load that library twice.

To fix it, we should remove it from tomviz-web. But when embedding in web pages that don't already load the polyfill, we should add the polyfill script along with the tomviz-web one.

[jourdain]

Remove that line

https://github.com/OpenChemistry/tomvizweb/blob/master/Source/tomviz-viewer.js#L7

Then when doing that https://openchemistry.github.io/tomvizweb/docs/ we should have both scripts

<script type="text/javascript" src="https://unpkg.com/babel-polyfill/dist/polyfill.min.js"></script>
<script type="text/javascript" src="https://unpkg.com/tomvizweb"></script>

[cryos]

Thanks @jourdain for explaining, I will take a look and try to get something pushed when I get a chance.

[cjh1]

@mrakitin Sorry for the delay, this issue is now resolved in the latest release of tomvizweb, see screenshot below. Thanks for the excellent instructions for the recreate.

[mrakitin]

@cjh1, thank you for resolving the issue, this is a really useful fix!