How to run shell script file using nodejs? - node.js

Question

I need to run a shell script file using nodeJS that executes a set of Cassandra DB commands. Can anybody please help me on this.
inside db.sh file:
create keyspace dummy with replication = {'class':'SimpleStrategy','replication_factor':3}
create table dummy (userhandle text, email text primary key , name text,profilepic)

Answer 1

You could use "child process" module of nodejs to execute any shell commands or scripts with in nodejs. Let me show you with an example, I am running a shell script(hi.sh) with in nodejs.
hi.sh
echo "Hi There!"
node_program.js
const { exec } = require('child_process');
var yourscript = exec('sh hi.sh',
(error, stdout, stderr) => {
console.log(stdout);
console.log(stderr);
if (error !== null) {
console.log(`exec error: ${error}`);
}
});
Here, when I run the nodejs file, it will execute the shell file and the output would be:
Run
node node_program.js
output
Hi There!
You can execute any script just by mentioning the shell command or shell script in exec callback.

Answer 2

You can execute any shell command using the shelljs module
const shell = require('shelljs')
shell.exec('./path_to_your_file')

Answer 3

you can go:
var cp = require('child_process');
and then:
cp.exec('./myScript.sh', function(err, stdout, stderr) {
// handle err, stdout, stderr
});
to run a command in your $SHELL.
Or go
cp.spawn('./myScript.sh', [args], function(err, stdout, stderr) {
// handle err, stdout, stderr
});
to run a file WITHOUT a shell.
Or go
cp.execFile();
which is the same as cp.exec() but doesn't look in the $PATH.
You can also go
cp.fork('myJS.js', function(err, stdout, stderr) {
// handle err, stdout, stderr
});
to run a javascript file with node.js, but in a child process (for big programs).
EDIT
You might also have to access stdin and stdout with event listeners. e.g.:
var child = cp.spawn('./myScript.sh', [args]);
child.stdout.on('data', function(data) {
// handle stdout as `data`
});

Answer 4

Also, you can use shelljs plugin.
It's easy and it's cross-platform.
Install command:
npm install [-g] shelljs
What is shellJS
ShellJS is a portable (Windows/Linux/OS X) implementation of Unix
shell commands on top of the Node.js API. You can use it to eliminate
your shell script's dependency on Unix while still keeping its
familiar and powerful commands. You can also install it globally so
you can run it from outside Node projects - say goodbye to those
gnarly Bash scripts!
An example of how it works:
var shell = require('shelljs');
if (!shell.which('git')) {
shell.echo('Sorry, this script requires git');
shell.exit(1);
}
// Copy files to release dir
shell.rm('-rf', 'out/Release');
shell.cp('-R', 'stuff/', 'out/Release');
// Replace macros in each .js file
shell.cd('lib');
shell.ls('*.js').forEach(function (file) {
shell.sed('-i', 'BUILD_VERSION', 'v0.1.2', file);
shell.sed('-i', /^.*REMOVE_THIS_LINE.*$/, '', file);
shell.sed('-i', /.*REPLACE_LINE_WITH_MACRO.*\n/, shell.cat('macro.js'), file);
});
shell.cd('..');
// Run external tool synchronously
if (shell.exec('git commit -am "Auto-commit"').code !== 0) {
shell.echo('Error: Git commit failed');
shell.exit(1);
}
Also, you can use from the command line:
$ shx mkdir -p foo
$ shx touch foo/bar.txt
$ shx rm -rf foo