execute a batch file from nodejs - node.js

Question

Would it be possible to run a batch file from a nodejs application?
After googling for some time we can use child_process to execute the commands. Tried the same module but without success.
Could somebody guide me?

Answer 1

This creates a NodeJS module with a single function named exec() to execute batch scripts.
var exec = require('child_process').exec,
path = require('path'),
os = require('os');
fs = require('fs');
// HACK: to make our calls to exec() testable,
// support using a mock shell instead of a real shell
var shell = process.env.SHELL || 'sh';
// support for Win32 outside Cygwin
if (os.platform() === 'win32' && process.env.SHELL === undefined) {
shell = process.env.COMSPEC || 'cmd.exe';
}
// Merges the current environment variables and custom params for the environment used by child_process.exec()
function createEnv(params) {
var env = {};
var item;
for (item in process.env) {
env[item] = process.env[item];
}
for(item in params) {
env[item] = params[item];
}
return env;
}
// scriptFile must be a full path to a shell script
exports.exec = function (scriptFile, workingDirectory, environment, callback) {
var cmd;
if (!workingDirectory) {
callback(new Error('workingDirectory cannot be null'), null, null);
}
if (!fs.existsSync(workingDirectory)) {
callback(new Error('workingDirectory path not found - "' + workingDirectory + '"'), null, null);
}
if (scriptFile === null) {
callback(new Error('scriptFile cannot be null'), null, null);
}
if (!fs.existsSync(scriptFile)) {
callback(new Error('scriptFile file not found - "' + scriptFile + '"'), null, null);
}
// transform windows backslashes to forward slashes for use in cygwin on windows
if (path.sep === '\\') {
scriptFile = scriptFile.replace(/\\/g, '/');
}
// TODO: consider building the command line using a shell with the -c argument to run a command and exit
cmd = '"' + shell + '" "' + scriptFile + '"';
// execute script within given project workspace
exec(cmd,
{
cwd: workingDirectory,
env: createEnv(environment)
},
function (error, stdout, stderr) {
// TODO any optional processing before invoking the callback
callback(error, stdout, stderr);
}
);
};

Answer 2

I have found the solution for it.. and its works fine for me. This opens up a new command window and runs my main node JS in child process. You need not give full path of cmd.exe. I was making that mistake.
var spawn = require('child_process').spawn,
ls = spawn('cmd.exe', ['/c', 'startemspbackend.bat']);
ls.stdout.on('data', function (data) {
console.log('stdout: ' + data);
});
ls.stderr.on('data', function (data) {
console.log('stderr: ' + data);
});
ls.on('exit', function (code) {
console.log('child process exited with code ' + code);
});

Answer 3

An easier way I know for executing that is the following code :
function Process() {
const process = require('child_process');
var ls = process.spawn('script.bat');
ls.stdout.on('data', function (data) {
console.log(data);
});
ls.stderr.on('data', function (data) {
console.log(data);
});
ls.on('close', function (code) {
if (code == 0)
console.log('Stop');
else
console.log('Start');
});
};
Process();