[Troubleshooting] PHP 8.1 site with Xdebug causes Bad Gateway error

[incon]

Is there an existing issue for this?

• I have searched the existing issues

Current Behavior

502 Bad Gateway

Expected Behavior

Turning on Xdebug makes every request return a 502 Bad Gateway error

Steps To Reproduce

Turn on Xdebug and try to debug.

Environment

- macOS: 14.3.1
- Valet: 4.6.1
- PHP Monitor: 7.0.1

Do you have a log file (or a screenshot) or any additional information?

No response

[nicoverbruggen]

Hmm... Bad gateway errors are usually resolved by restarting nginx and PHP.

Can you restart the Valet services via the menu item and let me know if that solved the issue? (You can also try "Fix My Valet", actually)

If neither works, can you let me know the output of php -v?

[incon]

PHP 8.1.27 (cli) (built: Dec 19 2023 20:35:55) (NTS)
Copyright (c) The PHP Group
Zend Engine v4.1.27, Copyright (c) Zend Technologies

[incon]

Works fine if I switch to PHP 8.3 but I run this project on PHP 8.1 in production and I would like my local and production versions match.

[incon]

When Xdebug is on

PHP 8.1.27 (cli) (built: Dec 19 2023 20:35:55) (NTS)
Copyright (c) The PHP Group
Zend Engine v4.1.27, Copyright (c) Zend Technologies
    with Xdebug v3.3.1, Copyright (c) 2002-2023, by Derick Rethans

[nicoverbruggen]

So this is only happening with PHP 8.1, correct?

And you installed xdebug via the extension manager for that PHP version?

[nicoverbruggen]

With gateway errors you can probably find more information by checking the output of ~/.config/valet/Log/php-fpm.log.

Try running cat ~/.config/valet/Log/php-fpm.log and let me know what's in there. It probably contains a bunch of warnings there.

[incon]

2024/02/22 17:58:12 [error] 94673#0: *13 upstream prematurely closed connection while reading response header from upstream, client: 127.0.0.1, server:

[incon]

So this is only happening with PHP 8.1, correct?

And you installed xdebug via the extension manager for that PHP version?

Yes and I have tried installing the extension via the manager.

[nicoverbruggen]

Ah, the dreaded premature closed connection w/o much context.

1. Are your PHP versions up-to-date (you can check via the PHP version manager)? If not, you may be dealing with an outdated version of PHP 8.1, which isn't compatible with the binaries of PHP 8.1's xdebug that were installed via the extension manager... you can try updating/upgrading.

2. Alternatively, it may be related to this issue, in which case you can try this workaround but if you are on a recent version of Valet (and it seems you are) it may be enough to simply run valet install again.

[incon]

Everything is up to date and I've tried valet install

[nicoverbruggen]

Can you try the workaround I've linked?

[incon]

Tried

;Signal 11 workaround
env['PGGSSENCMODE'] = disable
env['LC_ALL'] = C

Didn't work

Tried deleting the sock and installing Valet again didn't work.

[incon]

If I disable Xdebug everything works the issue is only when Xdebug is loaded.

[nicoverbruggen]

@incon I meant this workaround, updating the plist file. (The PGGSSENCMODE workaround is specific to PostgreSQL and is probably not the cause here.)

Give that a try! When you installed Xdebug, was PHP 8.1 the globally linked PHP version, or not? If the workaround doesn't work I want to see if I can reproduce this issue on my own system.

[incon]

I noticed PGGSSENCMODE was already included.

I've tried to remove everything and set everything up again

Removed brew
/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/uninstall.sh)"

Removed items not removed by brew uninstall
sudo rm -rf /opt/homebrew

Removed Valet config
rm -rf ~/.config/valet/

Removed global composer
rm -rf ~/.composer/

Reinstall brew

brew install [email protected]
brew install composer // installed php 8.3
composer global require laravel/valet
valet install
brew tap shivammathur/extensions

Launched phpmon
Open View Domains List and set the project I want to be in PHP 8.1
Install Xdebug via the extension ui.
Configure 20-xdebug.ini with

xdebug.mode=debug,develop
xdebug.start_with_request=yes
xdebug.start_upon_error=yes

502 Bad Gateway

[incon]

Switch the site to PHP 8.3 and install extension via ui, configure Xdebug and it works correctly.

[incon]

Issue is only when in isolation mode or not set on PHP 8.3

[nicoverbruggen]

I'm trying to reproduce this issue and unfortunately this seems to work correctly here. I've made sure to try both PHP 8.1 linked and isolated (with PHP 8.3 as the primary version and using site isolation). As you can see:

What kind of project are you trying to use with Valet?

Can you try a simple site? Here's a basic test, that's the one I just did:

1. Make a new folder and set it to use PHP 8.1 (via View Domains List...) -> I used phpinfo as the folder name
2. Create index.php
3. Add phpinfo() (see below)
4. Navigate to the folder name .test (in my case: phpinfo.test)

<?php

phpinfo();

Does that work? Or are you also getting an error this way? It's always possible that your PHP script itself causes the issue.

It's worth checking the nginx log too... cat ~/.config/valet/Log/nginx.log -- maybe there's something useful in there.

[incon]

Only when Xdeug is connected to a debuger is when I get the issue.

[nicoverbruggen]

Ah, I see.

This may very well be a Xdebug or configuration issue that I'm not familiar with... from what I can tell, the app has correctly installed the extension.

How are you debugging with Xdebug? What IDE? What browser? I'll see if I can't repro it on my end.

[incon]

Tested a phpinfo.test and it worked with debuging turn on.

[incon]

I just tried a blank Laravel project and it worked also.

[incon]

I've tried PHPStorm my normal editor and VS Code with the Xdebug plugin.

[nicoverbruggen]

Hmm... in that case I don't think I can help you any further, as it's likely an issue with that specific site or project, right?

At the very least, I'm going to move this topic to Discussions, should anyone bump into a similar problem they can find this thread there under the troubleshooting section.