🐛 BUG: astro preview stopped working

[herteleo]

What version of astro are you using?

0.26.1

What package manager are you using?

npm

What operating system are you using?

Mac

Describe the Bug

npm run preview starts without error but shows ERR_CONNECTION_REFUSED if you try to open http://localhost:3000/ in the browser.

Link to Minimal Reproducible Example

https://stackblitz.com/edit/github-uy2pjg?file=package.json

Participation

• I am willing to submit a pull request for this issue.

[SebasG22]

• This is failing on 1.0.0-beta.0

[SlicedSilver]

I'm also experiencing this bug (also on a mac).

What appears to be happening is that the preview command runs without any errors and immediately quits back to the terminal. I tried running the command with the --verbose flag and with the debug env variables DEBUG=astro:*,vite:* astro preview but nothing is reported.

[SlicedSilver]

astro/packages/astro/src/cli/index.ts

Lines 139 to 145 in 50bd14a

	case 'preview': {
	try {
	return await preview(config, { logging }); // this will keep running
	} catch (err) {
	return throwAndExit(err);
	}
	}

I've noticed that the preview function above is immediately resolving (on my setup) and thus not staying open. I wasn't able to see any recent changes that explain why this behaviour has changed.

astro/packages/astro/src/core/preview/index.ts

Line 109 in 50bd14a

resolve();

---

A naive solution seems to be changing the code to resemble the dev function by adding a return await new Promise(() => {});. Not sure what the knock-on effects of this change would be, but it does seem to resolve the issue on my device.

case "preview": {
      try {
        await preview(config, { logging });
        return await new Promise(() => {
        });
      } catch (err) {
        return throwAndExit(err);
      }
    }

Hopefully this helps to track down the root cause.

[idrakimuhamad]

Running preview in 1.0.0-beta.2 will display below and the task stopped. I've tried running build first and the preview but its just the same.

🚀  astro  v1.0.0-beta.2 started in 2ms
  
  ┃ Local    http://localhost:3000/
  ┃ Network  use --host to expose

[hippotastic]

The same error happens on Windows 10 for me. Preview starts and outputs the URL, but then it exits immediately.

[karthik-srinivas]

yes this is happening for me as well

the process is getting terminated just after running preview in my case serve

version - "astro": "^1.0.0-beta.2"

when I tested it, version "astro": "^0.25.2" is working fine

[tony-sull]

Thanks for all the debugging and details in this issue! Just merged #3004 with a fix