带有nodejs child_process的ssh，在服务器上找不到命令

Question

I'm attempting to run a simple ssh command, via nodejs child_process. when i run the command via nodejs code, it fails saying the command that i sent to the server was not found. when i run the same command just copy & pasting to my terminal window, it runs fine.

here is the command line version of what i'm trying to do :

ssh user@example.com 'ls -lai'

and here is the nodejs version of the same ssh command, using child_process

var cproc = require('child_process');
var exec = cproc.exec;
var spawn = cproc.spawn;

var command = "ssh";
var args = ["user@example.com", "'ls -lai'"];

var child = spawn(command, args);

child.stdout.on('data', function(data) {
  console.log('stdout: ' + data);
});

child.stderr.on('data', function(data) {
  console.log('stderr: ' + data);
});

child.on('close', function(code) {
  console.log('exit code: ' + code);
  process.exit();
});

the output from the command line version is exactly what i expect... i get the directory listing. but when i run this nodejs code to execute the same command, the stderr callback code kicks in, and the command returns code 127 (command not found).

$ node test-ssh.js 
stderr: bash: ls -lai: command not found

exit code: 127

according to the output here, the 'ls -lai' command is not found... but that doesn't make sense, as it works perfectly fine when i run this from my terminal prompt directly.

anyone know why running ssh through nodejs would cause this to happen?

Answer 1

turns out the single quotes around the remote command were the problem.

var args = ["user@example.com", "ls -lai"];

and it works

Answer 2

I had this problem too but I thought the quotes were a necessity for me due to me trying to run multiple commands at once, and I kept trying to find a way around it.

For example:

var args = ["user@example.com", "'cd ~ && ls -lai'"]

would break. However, you can still omit the quotes and everything will execute correctly through SSH since child_process will pass it as a single argument:

var args = ["user@example.com", "cd ~ && ls -lai"]