How to run Python Script from node js

Question

I have an api in node js in which I am trying to execute the python Script

My Directory structure is as below

 Nodejs_application
    index.js

 Python_application
    script1.py

I just have print("Hello World") in my script1.py

I have tried the below code in node js to run the python script

const {spawn} = require('child_process');

var dataToSend;
 // spawn new child process to call the python script
 const python = spawn('python', [__dirname+'../../../../pythoncode/script1.py']);
 // collect data from script
 python.stdout.on('data', function (data) {
  console.log('Pipe data from python script ...');
  dataToSend = data.toString();
 });
 // in close event we are sure that stream from child process is closed
 python.on('close', (code) => {
 console.log(`child process close all stdio with code ${code}`);
 // send data to browser
 res.send(dataToSend)   
 });

I am getting code 9009 error. Where did I go wrong?

Alternative code which I tried

  const {PythonShell} =require('python-shell');
  
  let options = {
    mode: 'text',
    pythonOptions: ['-u'], // get print results in real-time
    //  scriptPath: 'path/to/my/scripts', //If you are having python_test.py script in same folder, then it's optional.
   // args: ['shubhamk314'] //An argument which can be accessed in the script using sys.argv[1]
};
 

PythonShell.run('script1.py', options, function (err, result){
      if (err) throw err;
      // result is an array consisting of messages collected
      //during execution of script.
      console.log('result: ', result.toString());
      res.send(result.toString())
});

Error I am getting is

 PythonShellError: Python was not found; run without arguments to install from the Microsoft Store, or disable this shortcut from 

Settings > Manage App Execution Aliases.

In CMD I have given "python", I am getting

Python 3.10.0 (tags/v3.10.0:b494f59, Oct 4 2021, 19:00:18) [MSC v.1929 64 bit (AMD64)] on win32 Type "help", "copyright", "credits" or "license" for more information.

Answer 1

seems like you are not providing the correct python path and python is not configured on your path and hence not recognized as 'python'.

take a look at:

• C:\Python36
• C:\Users(Your logged in User)\AppData\Local\Programs\Python\Python36

or try running:

where python

in order to get full path.

additionally i would recommend you to use a package for running your script.

you can check this package on npm- native-python

it provides a very simple and powerful way to run python functions from node might solve your problem. import { runFunction } from '@guydev/native-python'

const example = async () => {
   const input = [1,[1,2,3],{'foo':'bar'}]
   const { error, data } = await runFunction('/path/to/file.py','hello_world', '/path/to/python', input)

   // error will be null if no error occured.
   if (error) {
       console.log('Error: ', error)
   }

   else {
       console.log('Success: ', data)
       // prints data or null if function has no return value
   }
}

python module

# module: file.py

def hello_world(a,b,c):
    print( type(a), a) 
    # <class 'int'>, 1

    print(type(b),b)
    # <class 'list'>, [1,2,3]

    print(type(c),c)
    # <class 'dict'>, {'foo':'bar'}