Node.js child processes to run python code not responding - node.js

Question

I have an Express Node.js application, but I want to run python code (send data and receive results)
but when I'm testing it using postman still loading and I don't have any response.
my node.js code
router.get('/name', callName);
function callName(req, res) {
var exec = require("child_process").exec;
var process = exec('python',["./hello.py",
req.query.firstname,
req.query.lastname
] );
process.stdout.on('data', function(error,data) {
console.log('stderr: ', error);
res.send(data.toString());
} )
}
python code
import sys
# Takes first name and last name via command
# line arguments and then display them
print("Output from Python")
print("First name: " + sys.argv[1])
print("Last name: " + sys.argv[2])
# Save the script as hello.py
thank you #nijm I found the solution
first The child_process.exec method doesn't accept the command arguments as an array (like child_process.spawn does).
second,
u must have python installed on ur machine.
third
u must have python file in a public folder (in my case uploads folder)
all these steps don't mention in any tutorial or an example about How to call a Python function from Node.js
at the end of the day, my code is
router.get('/name', callName);
function callName(req, res) {
var exec = require("child_process").exec;
exec(`python uploads/hello.py ${req.query.firstname} ${req.query.lastname}`, (error, stdout, stderr) => {
if (error) {
console.error(`exec error: ${error}`);
return;
}
console.log(`stdout: ${stdout}`);
console.log(`stderr: ${stderr}`);
});
}
python code
import sys
# Takes first name and last name via command
# line arguments and then display them
print("Output from Python")
print("First name: " + sys.argv[1])
print("Last name: " + sys.argv[2])
# Save the script as hello.py

Answer 1

The child_process.exec method doesn't accept the command arguments as an array (like child_process.spawn does), try this (untested):
var exec = require("child_process").exec;
exec(`python ./hello.py ${req.query.firstname} ${req.query.lastname}`, (error, stdout, stderr) => {
if (error) {
console.error(`exec error: ${error}`);
return;
}
console.log(`stdout: ${stdout}`);
console.log(`stderr: ${stderr}`);
});