Question

我在Raspberry Pi上的node.js中编写了一个服务器。我想从它运行一个python脚本，但它不执行该行。在以前的实例中，我已经运行文件但是来到socket.io的这个实例我无法运行该文件！虽然控制台显示从客户端传递给它的准确输出但它无法读取文件。插座负责移动。

/*jshint esversion: 6 */
var express = require('express');
// library for executing system calls
const spawn = require('child_process').spawn;
var XMLHttpRequest = require("xmlhttprequest").XMLHttpRequest;
app = express();
server = require('http').createServer(app);
io = require('socket.io').listen(server);
var colour = require('colors');
var ip = require('ip');

var PortNumber = 3000;

var xPos = 0, yPos = 0;

server.listen(PortNumber);
app.use(express.static('public'));


io.sockets.on('connection', function (socket) {

    socket.emit('ip', {value: 'http://' + ip.address() + ':8081'});

    // otp generation socket
    socket.on('userEmail', function (data) {
        var userEmail = data.value;

        // system call to generate OTP
        const OTPgeneration = spawn('python', [__dirname + '/python/OTPgeneration.py', userEmail]);
        OTPgeneration.stdout.on('data', (data) => {
            console.log(`${data}`);
        });
    });

    // otp submit button socket
    socket.on('userOtp', function (data) {
        var userOtp = data.value;
        console.log(userOtp);

        // system call to generate OTP
        const otpValidate = spawn('python', [__dirname + '/python/OTPvalidation.py', userOtp]);
        otpValidate.stdout.on('data', (data) => {
            console.log(`${data}`);

            // Get last output from python file
            var lastChar = `${data}`.slice(-2);

            if (lastChar === '0\n') {
                console.log('Wrong OTP');
            }
            else io.sockets.emit('otpConformation', {value: 'confirm'}); //sends the confirmation to all connected clients
        });
    });

    // x y values socket
    socket.on('servoPosition', function (data) {
        servoPosition = data.value;
        // servoPosition[0] is x and servoPosition[1] is y
        console.log('Reveived X: ' + servoPosition[0] + '  Y: ' + servoPosition[1]);
        // system call for i2c comminication
        const i2cData = spawn('python', [__dirname + '/python/sendI2C.py', servoPosition[0], servoPosition[1]]);
        i2cData.stdout.on('data', (data) => {
            console.log(`${data}`);
        });
    });

    // movement socket
    socket.on('movement', function (data) {
        var m = data.value;
            console.log("Movement :" + m);
  const submitMove = spawn('python', [__dirname + '/python/move.py', m]);
        submitMove.stdout.on('data', (data) => {
            console.log(`${data}`);
        });

    });
});

console.log('Server Running @'.green + ip.address().green + ":3000".green);

function readTextFile(file) {
    var rawFile = new XMLHttpRequest();
    //var rawFile = new XMLHttpRequest();
    rawFile.open("GET", file, false);
    rawFile.onreadystatechange = function () {
        if(rawFile.readyState === 4) {
            if(rawFile.status === 200 || rawFile.status === 0) {
                allText = rawFile.responseText;
                //alert(allText);
            }
        }
    };
    rawFile.send(null);
}

Answer 1

虽然使用Node的本机“child_process”模块是性能最高的选项，但让它工作起来可能会很乏味。快速解决方案是使用node-cmd模块。运行npm i node-cmd --save进行安装。通过服务器文件顶部的var cmd = require('node-cmd');导入。然后，

var pyProcess = cmd.get('python YOURPYTHONSCRIPT.py',
              function(data, err, stderr) {
                if (!err) {
                  console.log("data from python script " + data)
                } else {
                  console.log("python script cmd error: " + err)
                  }
                }
              );

根据需要进行编辑。 node-cmd有两种方法可以调用它，get和run。 run只运行提供的CLI命令，而get提供回调的使用，允许更好的错误处理，并使stdin，stdout，stderr之间的工作更进一步更容易。

如何从节点js

1 个答案: