Python node is warning "Error while sending a command."

[wooddenbowl]

Helllo Knime team members:
I’ve set python enviroment configuraion at “conda” and installed python3 conda enviroment and openpyxl.
but when I am running lines in python scirpt node, the node is warnning Error while sending a command.
Strangely after I switched to original python enviroment “Bundle”, everything is OK.
please advise how I can use openpyxl well under the conda enviroment.

Thanks in advance

[steffen_KNIME]

Hi @wooddenbowl,

could you please send us the log?
Which KNIME Analytics version did you use? Could you send a dump of the used environment please?

Thanks in advance!
Steffen

[wooddenbowl]

Hi Steffen
Sorry for late reply. My version is 4.7.2. Please look at the below images of the log.

[bwilhelm]

Hi @wooddenbowl,
Somehow the communication between the Java process and the Python process (via py4j) does not work. Can you please post a list of the packages installed in the Conda environment? (conda list -n <env_name>)

Does the script work when executed in the console directly?

[wooddenbowl]

Hi bwilhelm
The attachment is what I’ve installed in Py3 _conda_enviroment.
By the way, I’ve runned my python script both inside the node and the console
conda_list.txt (24.6 KB)

[bwilhelm]

Hi @wooddenbowl,
The file that you sent shows the content of the “base” environment. I guess this is not the environment that you are using, right? Did the script work when you executed it in the console?

[wooddenbowl]

Hello bwilhelm
please find the attachment of my py3_knime package list. The script fails with openpyxl and the console is warning.
py3_knime.txt (13.0 KB)

[bwilhelm]

The list of packages looks fine. Everything necessary is included.

@wooddenbowl

The script fails with openpyxl and the console is warning.

Can you elaborate? What happens if you copy the code into a Python script file (without the first and last line but maybe add a print(df) to see the output) and execute it in the “py3_knime” environment with python path_to_the_script.py?

[wooddenbowl]

pleas find the attached docs.
conda_py3_knime.docx (244.4 KB)

[bwilhelm]

Hi @wooddenbowl,
This we already established that the script does not work in the “Python Script” node with your “py3_knime” environment. I am asking you to verify that the Conda environment contains a working Python installation (that is able to run the script) without the use of KNIME (just to find where the issue happens).

[wooddenbowl]

Hi
Please look at the following image

[mlauber71]

@wooddenbowl you might want to check this article about how to set up a conda environment and connect it to KNIME. It might be best to start from scratch.

KNIME and Python — Setting up and managing Conda environments