Google Colab 403 Unauthorized response

[bcliang]

Rather than provide my own example, here's a broken example available from the dash-sample-apps repository.

https://github.com/plotly/dash-sample-apps/tree/master/apps/dash-image-enhancing

The prototypical example in the docs also fails.

Searching online, there were some reports of google putting new restrictions in place on colab compute instances.

!pip list
...
jupyter                       1.0.0          
jupyter-client                5.3.5          
jupyter-console               5.2.0          
jupyter-core                  4.7.0          
jupyter-dash                  0.3.1
..

[gggrafff]

I had this problem. This parameters (host and port) helped me:

app.run_server(mode='inline', host='localhost', port=1050)

Developers of dash could solve this problem by using another default port in colab (old port in other cases might provide a back compatibility). Check if a notebook is running on colab: https://stackoverflow.com/a/53586419/12903113