Bug Reporting Best Practices

Hello Bug Reporters!

I would like to share some of best practices on reporting bugs you encounter while working with KNIME.

First to say tnx to those who are already following these or similar practices and encouraging others to do so. Secondly, as much as bugs are annoying and not pleasant to see I think that this kind of feedback is also very valuable and hopefully there will be once a series of badges to acknowledge it. Finally to say that place for reporting bugs is by opening a topic on KNIME Forum. To open a topic you need to be registered.

Before you open a topic

  • Use forum search to check if what you have encountered is already discussed in another topic. Maybe you’ll find out that it is not a bug. Maybe it is a bug but you are using an older version and it has already been solved in new one. Maybe there is already a topic where it was confirmed that it is a bug and ticket has been created but not solved. (In this case you can join discussion saying you encountered it and we’ll give +1 on ticket or just reply with “+1” - this helps with prioritization). In last case if topic is closed you can open a new about it and link closed one so +1 can be given.
  • Additionally you can check node’s description, KNIME documentation and/or FAQ to be sure your understanding of bug is correct

When you decided to open a topic

Read topic till the end and if possible provide following details:

  • Bug description. In short what is the problem you have encountered, error message you are seeing, incorrect data you are getting, steps that were made or whatever the bug might be about
  • Reproducible (minimal) workflow example. It is a workflow example that can successfully reproduce described bug. You can attach it to a topic (via drag and drop or attachment icon) or add to your space on KNIME Hub and link it. Keep in mind that bug needs to be reproducible in order to be verified and subsequently fixed.
  • The version of KNIME Analytics Platform and relevant extensions are you using. This can be obtained via Help --> About KNIME Analytics Platform --> Installation Details
  • The operating system you are running (e.g. Windows 10, macOS 10.13.4, Ubuntu 16.04.3, …)
  • KNIME log file. You can open the KNIME log via View --> Open KNIME log or open the log file located at {workspace_directory}/.metadata/knime/knime.log. Make sure to configure log level to DEBUG level cause log file then contains maximum information (this can be done via File --> Preferences --> KNIME )
  • Generate a stack trace (only if you are asked by one of the developers):
    • Download VisualVM
    • Start VisualVM and look for a Local Application in the Applications Window
    • Right click on it and select Thread Dump (or Heap Dump depending on which is requested from you)
    • Use File--> Save As… to save it to a file
    • Attach saved file to topic
  • And any specific configuration/setting you have in place that might help

Feel free to use logic and if you think workflow example with short description is enough there is no need for all details to be given and time wasted.

Happy KNIMEing!