fix(#2981): keeps astro preview server alive

[tony-sull]

Changes

Fixes a bug that was preventing the astro preview server from staying alive

Testing

Tested locally

Docs

Bug fix only

[changeset-bot]

🦋 Changeset detected

Latest commit: 1673c71

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
astro	Patch

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[matthewp]

Hm, I'm not sure about this. I don't love the idea of returning a promise that never results as a way to prevent the server from closing. Look at the code for preview it doesn't look like the server should be closing when the function completes. Why is it doing so?

[caioferrarezi]

Hi, @tony-sull!

I was looking for a solution based on what @matthewp has said and I found this promise chaining added in the main process when the CLI is called https://github.com/withastro/astro/blame/a68885c0d62018b74d1a5c30395d237829b72c61/packages/astro/astro.js#L100

It seems like the .then(() => process.exit(0)) is killing the node environment when the preview's server promise resolution is executed here https://github.com/withastro/astro/blob/main/packages/astro/src/core/preview/index.ts#L109

Hope it may help!

Thanks!

[tony-sull]

Hm, I'm not sure about this. I don't love the idea of returning a promise that never results as a way to prevent the server from closing. Look at the code for preview it doesn't look like the server should be closing when the function completes. Why is it doing so?

For astro preview the CLI was returning a promise that only tracked when the server was opened so it killed the process right away

I did find a cleaner solution here though, wrapped the server's close and error events in a promise so the CLI is actually going to track the server instance itself

[natemoo-re]

Nice solution! LGTM.