I am trying to access data from google play store using GSUTIL in nodejs.
when I run the following command on my command line, I am able to get the files:
gsutil cp -r gs://mybucket /mylocalmachine
How do I run this command on my node server to get the same result? The below code doesnot yield any result
var exec = require('child_process').exec;
function copyUsingGSUTIL() {
return new Promise(function (resolve, reject) {
var child = exec("gsutil cp -r", ["gs://mybucket", "mylocalmachine"],{cwd:"/Applications/gsutil"});
console.log(child)
child.on('close', function (code) {
console.log('Exit code' + code);
});
});
}
gsutil is a python program so you have to invoke python and use the full paths in the exec command like
String command = "python c:/gsutil/gsutil.py cp -r gs://mybucket/mylocalmachine" + "C:/your absolute path here/Applications/gsutil";
...
...
var child = exec(command);
console.log(child);
...
...
There is also a java alternative for gsutil see this https://developers.google.com/api-client-library/java/apis/storage/v1
See also this thread Google cloud storage gsutil tool with Java
Related
I'm writing a small utility tool for development to sync files over ssh. Normally I use ssh-agent set up in .bashrc file to connect to my dev server easily. I'd like to use exec in the script, but calling ssh-agent, every time I make a request sounds a bit inoptimal.
Is there a way I could execute the agent code once, and then have it working for all subsequent ssh requests I make? E.g. to spawn a shell process like a terminal emulator, and then use that process to execute a command, rather than invoking a new shell with each command.
The reason I want to do this, is I don't want to store the password in a config file.
You can create one ssh process, and then execute other commands using same process. Here is an example how to use it for bash. I'm creating a new bash shell and execugte the command ls -la and exit you can execute other commands.
const cp = require("child_process")
class MyShell {
constructor(command) {
this._spawned = cp.spawn(command, {
stdio: ["pipe", "pipe", "inherit"],
})
}
execute(command, callback) {
this._spawned.stdin.write(command + "\n")
this._spawned.stdout.on("data", (chunk) => {
if (callback) {
callback(chunk.toString())
}
})
}
}
var myShell = new MyShell("bash")
myShell.execute("ls -la", (result) => {
console.log(result)
})
myShell.execute("exit")
I'm trying to change the directory of terminal using with Node.js program but not able to achieve it. Script is run as node app.js dir_name so first I'm creating the directory and then trying to change into that directory using cd command. Directory is created but the directory for terminal is not changed.
#!/usr/bin/env node
var platform = process.platform;
var figlet = require('figlet');
var chalk = require('chalk');
if(process.argv.length < 3){
console.log(
chalk.green(
figlet.textSync('mdcd', { horizontalLayout: 'full' })
)
);
console.log(chalk.red("Please provide a directory name"));
}else{
if(platform.includes("win")){
//console.log("Its Windows");
}else {
var exec = require('child_process').exec;
var command_1 = "mkdir "+process.argv[2];
var command_2 = "cd "+process.cwd()+"/"+process.argv[2];
exec(command_1, function (error, stdout, stderr) {
if(error){
console.log("Something bad happened"+error);
}else {
exec(command_2, function (error, stdout, stderr) {
if(error){
console.log("Something bad happened"+error);
}
});
}
});
}
}
command prompt directory from Node.js script
You cannot change the command prompt directory. Basically you have the process tree:
cmd / term
| -> NodeJs
You shouldn't change the working dir for cmd. However there are command you can execute to change the working dir of any process e.g. https://unix.stackexchange.com/a/282009
More
You can however change the the working dir for the nodejs process (which is what I suspect you want to do) using process.chdir https://nodejs.org/api/process.html#process_process_chdir_directory
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)
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.
You can execute any shell command using the shelljs module
const shell = require('shelljs')
shell.exec('./path_to_your_file')
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 $PATH.
You can also go
cp.fork('myJS.js', function(err, stdout, stderr) {
// handle err, stdout, stderr
});
to run a javascript file with node.js, but in a child process (for big programs).
EDIT
You might also have to access stdin and stdout with event listeners. e.g.:
var child = cp.spawn('./myScript.sh', [args]);
child.stdout.on('data', function(data) {
// handle stdout as `data`
});
Also, you can use shelljs plugin.
It's easy and it's cross-platform.
Install command:
npm install [-g] shelljs
What is shellJS
ShellJS is a portable (Windows/Linux/OS X) implementation of Unix
shell commands on top of the Node.js API. You can use it to eliminate
your shell script's dependency on Unix while still keeping its
familiar and powerful commands. You can also install it globally so
you can run it from outside Node projects - say goodbye to those
gnarly Bash scripts!
An example of how it works:
var shell = require('shelljs');
if (!shell.which('git')) {
shell.echo('Sorry, this script requires git');
shell.exit(1);
}
// Copy files to release dir
shell.rm('-rf', 'out/Release');
shell.cp('-R', 'stuff/', 'out/Release');
// Replace macros in each .js file
shell.cd('lib');
shell.ls('*.js').forEach(function (file) {
shell.sed('-i', 'BUILD_VERSION', 'v0.1.2', file);
shell.sed('-i', /^.*REMOVE_THIS_LINE.*$/, '', 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
Not sure why this does not work, if I run a simple command such as cmd='ls -all' then I get the output back, but when I use this to run a command which takes some time to complete I don't get anything at all returned.
In this example, I am using lftp to mirror some folders and want to get the reply, if I run the command from the terminal then of course I see the output, but using child process I get nothing:
var childProcess = require('child_process');
var cmd = 'lftp sftp://user:password#somehost -e "mirror -R --delete --parallel=5 /usr/share/scripts/ /volumes/folders/usr/share/;bye"';
childProcess.exec(cmd, function (error, stdout, stderr) {
console.log('stdout:'+stdout);
console.log('stderr:'+stderr);
console.log('error:'+error);
});
I also tried the spawn method, nothing returned from that either:
var spawn = require('child_process').spawn;
var lftp = spawn('lftp',['sftp://user:password#somehost', '-e "mirror -R --delete --parallel=5 /usr/share/scripts/ /volumes/folders/usr/share/;bye"']);
lftp.stdout.on('data', function(data) {
console.log(data.toString());
});
I think the problem is that lftp buffers its output.
To get around that you'll need to use unbuffer (http://expect.sourceforge.net/example/unbuffer.man.html) to send the output directly to stdout.
How to exec continuously? e.g. ls after cd?
I tried
exec = require('child_process').exec;
exec('cd ~/',
function(){
exec('ls'),
function(err, stdout, stderr){
console.log(stdout); // this logs current dir but not ~/'s
}
}
)
exec('cd ~/').exec('ls', function(err, stdout, stderr){
console.log(stdout);
})//this also fails because first exec returns a ChildProcess Object but not itself.
It is not possible to do this because exec and spawn creates a new process. But there is a way to simulate this. You can start a process with exec and execute multiple commands in the same time:
In the command line if you want to execute 3 commands on the same line you would write:
cmd1 & cmd2 & cmd3
So, all 3 commands run in the same process and have access to the context modified by the previous executed commands.
Let's take your example, you want to execute cd ../ and after that to execute dir and to view the previous directory list.
In cmd you shoud write:
cd../ & dir
From node js you can start a process with exec and to tell it to start another node instance that will evaluate an inline script:
var exec = require('child_process').exec;
var script = "var exec = require('child_process').exec;exec('dir',function(e,d,er){console.log(d);});";
script = '"'+script+'"';//enclose the inline script with "" because it contains spaces
var cmd2 = 'node -e '+script;
var cd = exec('cd ../ &'+cmd2,function(err,stdout,strerr)
{
console.log(stdout);//this would work
})
If you just want to change the current directory you should check the documentation about it http://nodejs.org/api/child_process.html#child_process_child_process_exec_command_options_callback
You can use nodejs promisify and async/await:
const { promisify } = require('util');
const exec = promisify(require('child_process').exec);
export default async function () {
const cpu = await exec('top -bn1');
const disk = await exec('df -h');
const memory = await exec('free -m');
const payload = {
cpu,
disk,
memory,
};
return payload
}
If you want to use cd first, better use process.chdir('~/'). Then single exec() will do the job.
You can call exec with cwd param like so:
exec('ls -a', {
cwd: '/Users/user'
}, (err, stdout) => {
if (err) {
console.log(err);
} else {
console.log(stdout);
}
})
But beware, cwd doesn't understand '~'. You can use process.env.HOME instead.