Pass array from python to external express.js-CodePudding

In the backend, I have a python program(vmstats.py) that stores string data in vmonoff[]:

vmstats.py

import json
from proxys import ProxyServer

vmonoff = []

proxys = ProxyServer('XXXXXX','UUUUUU','PPPPPP')

for b in proxys.listeners:
    if "MYVMNAME" in b.vname:
        if b.stat=="UP":
            vmonoff.append('./images/vm_on.png')
        else:
            vmonoff.append('./images/vm_off.png')
        
        print('{:<10}'.format(b.vname), '{:<8}'.format('Status:'), '{:>6}'.format(b.stat))

response = json.dumps(vmonoff)

exec.controller.js

const {exec} = require('child_process');
const path = require('path');
const fs = require('fs');
const htmlFile = path.join(__dirname, '/index.html');

exports.executeReport = (req, res) => {
    execute("python3 ./src/vmstats.py", res);

}

var responseObject = JSON.parse(response);

const execute = (command, res) => {
    exec(command, (error, stdout, stderr) => {
        if (error) {
            res.send({result: `error: ${error.message}`});
            return;
        }
        if (stderr) {
            res.send({result: `stderr: ${stderr}`});
            return;
        }
        createHtmlFile(stdout);
        res.sendFile(htmlFile);
        return;
    });
}

const createHtmlFile = (stdout) => {
    const rows = stdout.split('\n');
    const content = `<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Test</title>
</head>
<body>

<div >
    <div style="text-align: center">
    <h3>TEST</h3>
    <br>
    </div>

</div>

</body>
</html>`

    fs.writeFileSync(htmlFile, content);
}

In the frontend(exec.controller.js), I tried to use:

var responseObject = JSON.parse(response)

But I got the ReferenceError: response is not defined

How can I transfer vmonoff[] from python to the external express.js?

CodePudding user response：

First of all, it seems like your python script doesn't output anything to stdout (normally done with something like print), hence, Node JS have nothing to read from there.

Apart from that rows variable inside the createHtmlFile isn't used anywhere.

CodePudding user response：

in the python script you need to print the array:

response = json.dumps(vmonoff)
print(response)

and in the node script, stdout is where you get the data, and there you can parse it and process it further:

const execute = (command, res) => {
    exec(command, (error, stdout, stderr) => {
        if (error) {
            res.send({result: `error: ${error.message}`});
            return;
        }
        if (stderr) {
            res.send({result: `stderr: ${stderr}`});
            return;
        }
        var responseObject = JSON.parse(stdout);
        createHtmlFile(responseObject);
        res.sendFile(htmlFile);
        return;
    });
}

and then in createHtmlFile you can construct the HTML (for example, iterating array elements, or maybe using .join instead of .split, it's not clear what the HTML is supposed to look like..)