Reports without a chart cannot be screenshot by celery worker

[madsbuch]

Scheduled reporting and alerts use a celery worker. This worker authenticates users and renders a standalone reports page using Selenium and a headless browser. Finally, this is emailed.

It appears that Selenium is set to wait until the class slice_container is available (https://github.com/apache/superset/blob/master/superset/utils/webdriver.py#L130-L134). However, it seems like this class is only added to Charts (https://github.com/apache/superset/search?q=slice_container). Th problem occurs when no charts are available on reports.

I know this is an obscure conor case that probably don't merit too much change. However, it took me some time to debug this from the error I got

[2021-10-27 11:36:30,019: WARNING/MainProcess] Selenium timed out requesting url http://superset:8088/superset/dashboard/1/?standalone=3
Traceback (most recent call last):
  File "/app/superset/utils/webdriver.py", line 134, in get_screenshot
    (By.CLASS_NAME, "slice_container")
  File "/usr/local/lib/python3.7/site-packages/selenium/webdriver/support/wait.py", line 80, in until
    raise TimeoutException(message, screen, stacktrace)
selenium.common.exceptions.TimeoutException: Message: 

Report state: Report Schedule execution failed when generating a screenshot.

How to reproduce the bug

1. Create a dashboard without a chart
2. Setup a scheduled report
3. See that above-mentioned error is thrown

Expected results

To have the report screenshot and send

Actual results

Selenium times out.

Environment

(please complete the following information):

• browser type and version: GECKODRIVER_VERSION=0.29.0
• superset version: apache/superset:1.3.0, from dockerhub
• python version: As bundled in the docker image
• node.js version: As bundled in the docker image
• any feature flags active: FEATURE_FLAGS = {"ALERT_REPORTS": True}

Checklist

Make sure to follow these steps before submitting your issue - thank you!

• I have checked the superset logs for python stacktraces and included it here as text if there are any.
• I have reproduced the issue with at least the latest released version of superset.
• I have checked the issue tracker for the same issue and I haven't found one similar.

Additional context

Knowing when the page is rendered is a hard one. It might also be documentation or more verbose error handling that is the solution.

Let me know how to best contribute a solution to this, if that is an option.

[villebro]

@madsbuch this is indeed an unfortunate fringe case. I agree with your assessment, and you seem to have pinpointed the piece of code that would need to be modified to handle this specific case (potentially we might need to add/change some class names on the frontend components). Would you be open to taking this task on in the form of a PR? I would be happy to assist. Also, it would be interesting to hear about the use case to understand this need better (=dashboard without regular charts).

[ensky]

it would be interesting to hear about the use case to understand this need better (=dashboard without regular charts)

We faced the same problem by trying to add an alert to a dashboard with a pure markdown document. In our scenario, this dashboard is a "help" about how to use the superset. Obviously it is not a good choice to send an alert on this "help", however unfortunately it happend to be the dashboard I used to test whether the alert system is working ;(. It took me an afternoon to figure out the problem, and had a same conclusion with @madsbuch :D

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions. For admin, please label this issue .pinned to prevent stale bot from closing the issue.

[rusackas]

@madsbuch / @villebro / @ensky it seems this issue has gone silent for upward of a year. I'm tempted to close it, but don't want to be dismissive here. Is this still an issue in 2.0.x, and if so, would anyone still be able/willing to open a PR?

[sfirke]

I validated this just now on 3.0.0rc3. Agreed that it's low priority.

[rusackas]

Closing this older issue in favor of #25237
Please continue/relay any context onto that issue as needed.

As always in open-source, PRs welcome ❤️