Python Error: ModuleNotFoundError during execution in a Web App

Hi everyone,

I created a simple App in AppDesigner on Linux where I call a python function output = py.MyModule.myFunction()

In this py script I also import the opcua library. This works without problems.

Next, I complied it to a matlab web app (ctf file) and ran it on the same machine within the Matlab Web App Server.

I also added the MyModule.py File in Files required for your app to run in the Web App Compiler.

Moreover, I added the current folder to the python system path during the startup function and tried to load the opcua lib.

if isdeployed
   [filepath,~,~] = fileparts(mfilename('fullpath'));
   insert(py.sys.path, int64(0), filepath);
   ...
   py.importlib.import_module('opcua');
end

But at the start comes directly an error:

I have extra output the properties of the Python environment and compared it with the one in Matlab. It shows the same properties:

Now, unfortunately, I do not know what to do. Does anyone have an idea what the problem is?

Thanks in advance!

Answer 1

[Chaitanya]

Hello Christian,

I understand that you have built an app in Linux that uses python modules. However, while compiling it to a CTF file for deploying as a web app, you are receiving errors that python module.

At this point I am assuming that you have referred to the below given MATLAB Answer to configure the MATLAB Web App Server to use Python.

https://in.mathworks.com/matlabcentral/answers/1763835-how-to-configure-matlab-web-app-server-to-use-python

You may consider the following MATLAB Answers that can help you to resolve the issue.

1. https://in.mathworks.com/matlabcentral/answers/1763835-how-to-configure-matlab-web-app-server-to-use-python
2. https://in.mathworks.com/support/search.html/answers/2007282-unable-to-resolve-name-error-when-calling-python-from-matlab-web-app-server.html

I hope this helps!

[Christian Idzik]

Thanks!