Validation fails - possible timeout issue

Operating system

Mac 10.11.6

nbgrader --version

0.5.4

jupyterhub --version (if used with JupyterHub)

jupyter notebook --version

5.30

Expected behavior

I am trying to run a notebook which requires loading text data and running code to process it. Overall it takes around 2 minutes to run on my machine. It works fine when I run all the cells in the notebook and the grading also works. I therefore expect it to validate.

Actual behavior

Validation fails. I get an eror message, reproduced below.

(test-env) Tom$ nbgrader validate source/A0/*.ipynb
[ValidateApp | INFO] Validating 'PATH_TO_NOTEBOOK/source/A0/a0notebook.ipynb'
[ValidateApp | INFO] Executing notebook with kernel: python3
[ValidateApp | ERROR] Timeout waiting for execute reply (30s).
[ValidateApp | ERROR] Interrupting kernel

When I run this in the notebook I get the same error, along with the message that tests have failed. I have tried editing nbgrader_config.py to suppress any timeouts but to no avail.

Does anyone know why a notebook that otherwise runs fine would be failing the validation step?

[ocanevet]

I cannot make the c.ExecutePreprocessor.timeout work. My /home/jovyan/.jupyter/nbgrader_config.py contains

c = get_config()
c.CourseDirectory.course_id = "maths"
c.ExecutePreprocessor.timeout = -1

and running the following cell:

x = 3
for i in range(45):
    print(i)
    time.sleep(1)
# Set x = 10
### BEGIN SOLUTION
x = 10
### END SOLUTION

followed by a test:

assert x == 10, f"should be 10 and i is {i}"

produce the following validation output

The following cell failed:

assert x == 10, f"should be 10 and i is {i}"
---------------------------------------------------------------------------
AssertionError                            Traceback (most recent call last)
<ipython-input-5-d2ec54bfcf63> in <module>
----> 1 assert x == 10, f"should be 10 and i is {i}"

AssertionError: should be 10 and i is 29

showing that my timeout it still 30 seconds. Could you help? Thanks.

[lgpage]

Can you try changing the c.ExecutePreprocessor.timeout config option (see http://nbgrader.readthedocs.io/en/stable/configuration/config_options.html). It looks like the default is 30 seconds, which might be a bit slower than you want.