improve error reporting when wrong python runs

[yz5548]

Problem: when open a default worksheet with ipython and R, there is error popup "error no module named 'urllib2' "

BTW: looks like ipython is still working by typing "1+1", "1*6+7"

Environment:
OS: Win 7 64 bit
browser: google chorme
notebook version: 1.4.1-0-ge8427bf-windows

Log information
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ttp://www.apache.org/licenses/LICENSE-2.0

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ons under the License.
Port range 8800-8803 taken, searching...
Oct 14, 2015 1:58:11 PM com.twosigma.beaker.shared.module.util.GeneralUtilsImpl
readFile
INFO: ERROR reading file C:\Users\H141930.beaker\v1\config\beaker.pref.json
starting nginx instance (D:\Software\BeakerNotebook\beaker-notebook-1.4.1-0-ge84
27bf-windows/nginx)
[main] INFO org.eclipse.jetty.server.Server - jetty-8.1.13.v20130916
[main] INFO org.eclipse.jetty.server.AbstractConnector - Started SelectChannelCo
nnector@127.0.0.1:8806

Connecting to http://127.0.0.1:8805/

Running
0: D:\Software\BeakerNotebook\beaker-notebook-1.4.1-0-ge8427bf-windows\python\py
thon
1: D:\Software\BeakerNotebook\beaker-notebook-1.4.1-0-ge8427bf-windows/config/pl
ugins/eval/ipythonPlugins/ipython/ipythonPlugin
2: 8808
Done starting IPython
Running
0: D:\Software\BeakerNotebook\beaker-notebook-1.4.1-0-ge8427bf-windows\python\py
thon
1: D:\Software\BeakerNotebook\beaker-notebook-1.4.1-0-ge8427bf-windows/config/pl
ugins/eval/r/rPlugin
2: 8809
Done starting R

[scottdraves]

Thanks for the report.
Beaker is confused between Python2 and Python3.
How did you install IPython?

[yz5548]

using ANACONDA PYTHON 3.4 Windows 64-bit

https://www.continuum.io/downloads

[scottdraves]

Thank you. What happens if you restart beaker, make a a new empty notebook, open the language manager, and then click on Python3?
Does it turn green, stay yellow forever, or produce an error?

[yz5548]

Python3 is OK ( it turn green without any error msg). Ipython still have the error for the first time

[scottdraves]

Thanks again. I think the problem is Beaker assumes you install Python2 Anaconda, and then add Python3 in a virtualenv. Will have to think about how best to fix that, but in the meantime you should be good as long as you avoid the "IPython" (aka Python2) plugin.

Unfortunately most of the Python tutorials are written assuming Python2 :( So to run those tutorials you would need to change the language of each cell and also make any code changes required. Or you can just make new Python3 notebooks and copy and paste in code from Python2 tutorials.

Or you could uninstall anaconda & install 2&3 as Beaker expects, then everything should just work :)

Beaker should probably update our tutorials, it is time to switch the "default" to 3. This is a new issue.

Beaker should probably base our python plugins on jupyter protocols to get list of available languages. there is already an issue for this.

[scottdraves]

After a bit more research, I decided we should keep our default that users will install Python2 primarily, and Python3 as an option, and keep our documentation in Python2.

So the more complex issue of handling more exactly which Pythons and other languages are available to jupyter remains in issue 1731.

the thing i can change now to make this a better UX is to improve the error when users try to start python2 and get python3, we can detect this and report a nice error and point at the documentation instead of crashing.

[yz5548]

Thank you very much for the update