PowerShell-Host

PowerShell-Host is a JavaScript library which hosts a PowerShell process to allow running commands and getting the results back quickly. PowerShell Exceptions are intercepted and the Message property is emitted to stderr.

This implementation uses Promises to make things easy to use:

• Output on stderr will be rejected.
• Output on stdout will be resolved.

Installation

npm install powershell-host

Example

You can use the in-built ConvertTo-Json applet to make parsing the data easy.

1import { PowerShell } from 'powershell-host';
2
3const ps = new PowerShell();
4
5const run = async () => {
6    // Open a new PowerShell without any profile which might impede us
7    // We could use `shell: 'pwsh'` in the options to open a newer PowerShell if installed
8    await ps.open({ args: ['-NoProfile'] });
9
10    // Log any errors that might occur after opening
11    // such as invalid arguments in the open command above
12    ps.on('error', (err) => {
13        console.log(`ERROR: ${err}`);
14    });
15
16    // Log if shell exits for any reason
17    ps.on('exit', (code, signal) => {
18        // Will not log graceful exit we removed all listeners on close
19        console.log(`shell exited code:${code} signal: ${signal}`);
20    });
21
22    const json = await ps.exec('Get-PsDrive | Select Name, Root | ConvertTo-Json');
23    const obj = JSON.parse(json);
24    // Newer versions of PowerShell can use ConvertTo-Json -ToArray to avoid forcing an array here
25    const result = Array.isArray(obj) ? obj : [obj];
26    result.forEach((drive) => console.log(drive.Name));
27};
28
29run()
30    .catch((err) => {
31        console.error(`ERROR: ${err.message}`);
32    })
33    .finally(() => {
34        ps.close();
35        ps.removeAllListeners();
36    });