Empty response when using FrankenPHP with worker mode in Docker

[totop275]

Hi, I'm currently trying to upgrade an existing native PHP project to use FrankenPHP.

Everything works fine when using the static binaries, but when I try to run it with Docker, the server returns an empty response (no output at all).

I've followed the official documentation examples, even with the worker script provided, but I still get the same result. So I suspect there might be something wrong with my Docker container setup.

Is there any additional configuration required that's not mentioned in the documentation?
For example, do I need to use a custom Caddyfile, set any special environment variables, or add specific flags to make worker mode work properly in Docker?

Here’s the sample PHP code I’m testing with:

<?php
// index.php

// Prevent worker script termination when a client connection is interrupted
ignore_user_abort(true);

// Handler outside the loop for better performance (doing less work)
$handler = static function () {
    // Called when a request is received,
    // superglobals, php://input and the like are reset
    echo "Hello World";
};

$maxRequests = (int)($_SERVER['MAX_REQUESTS'] ?? 0);
for ($nbRequests = 0; !$maxRequests || $nbRequests < $maxRequests; ++$nbRequests) {
    $keepRunning = \frankenphp_handle_request($handler);

    gc_collect_cycles();

    if (!$keepRunning) break;
}

And this is the Docker command I’m using to run it:

docker run \
    -e FRANKENPHP_CONFIG="worker ./index.php" \
    -v $PWD:/app \
    -p 80:80 -p 443:443 -p 443:443/udp \
    dunglas/frankenphp

Any help would be greatly appreciated. Thank you!

[withinboredom]

Have you installed any needed extensions? The dockerized version comes with almost no extensions and you'll need to install them. FrankenPHP comes with https://github.com/mlocati/docker-php-extension-installer installed.

[withinboredom]

Oh, I just saw your example script. Did you set the worker stanza in the caddyfile? https://frankenphp.dev/docs/config/#caddyfile-config

[AlliBalliBaba]

I think the default root in the Caddyfile is /app/public. You'll have to put the worker file into a public directory or mount into the public directory

[totop275]

still the same

[AlliBalliBaba]

What do you see with curl -v http://localhost? Is it trying to upgrade to https?

[AlliBalliBaba]

You might also need to set

-e "SERVER_NAME=:80" 

when only using http locally within docker.

[totop275]

What do you see with curl -v http://localhost? Is it trying to upgrade to https?

yes it was trying to upgrade to https

You might also need to set

-e "SERVER_NAME=:80" 

when only using http locally within docker.

still empty response

[totop275]

I don't know why it's not found. Isn't it supposed to forward the request to the worker script?

If I move the worker to the public directory, it works, by the way. But I still don't understand why it needs to be in the public directory, then what's the purpose of using -e FRANKENPHP_CONFIG="worker ./index.php"?

[AlliBalliBaba]

The worker needing to be in the public directory is a limitation of the current routing Implementation (this will probably change in a future version).

The idea is basically the same as with traditional setups where you would try to serve static files and fall back to an index.php file. Routing with worker files works the same as with any other PHP file, which is why it needs to be located in the public directory.

[totop275]

Got it, thank you so much for the help!