[worker-mode] blank page

[sa-tasche]

What happened?

I get a blank page.

I use the worker example

<?php
function getCounter(): int {
    static $count = 0;
    return ++$count; // Increments across requests!
}

$handler = static function () {
    echo getCounter(); // 1, 2, 3, ... for each request on this thread
};

while (\frankenphp_handle_request($handler)) {
    // ...
}

Build Type

Static binary

Worker Mode

Yes

Operating System

GNU/Linux

CPU Architecture

x86_64

PHP configuration

phpinfo() output

(How?)

Relevant log output

Relevant log output

{
    "level":"info",
    "ts":1784557298.5655265,
    "logger":"http.log.access",
    "msg":"NOP",
    "request":{
        "remote_ip":"127.0.0.1",
        "remote_port":"45762",
        "client_ip":"127.0.0.1",
        "proto":"HTTP/1.1",
        "method":"GET",
        "host":"app.mitgedanken.eu",
        "uri":"/favicon.ico",
        "headers":{
            "Referer":[
                "https://app.mitgedanken.eu/"
            ],
            "Sec-Fetch-Dest":[
                "image"
            ],
            "Sec-Ch-Ua":[
                "\"Not;A=Brand\";v=\"8\", \"Chromium\";v=\"150\", \"Microsoft Edge\";v=\"150\""
            ],
            "Accept-Encoding":[
                "gzip, deflate, br, zstd"
            ],
            "User-Agent":[
                "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.0.0 Safari/537.36 Edg/150.0.0.0"
            ],
            "Sec-Fetch-Mode":[
                "no-cors"
            ],
            "Via":[
                "3.0 Caddy"
            ],
            "X-Forwarded-For":[
                "46.83.242.243"
            ],
            "X-Forwarded-Proto":[
                "https"
            ],
            "Accept":[
                "image/avif,image/webp,image/apng,image/svg+xml,image/*,*/*;q=0.8"
            ],
            "Sec-Ch-Ua-Mobile":[
                "?0"
            ],
            "Sec-Fetch-Site":[
                "same-origin"
            ],
            "X-Forwarded-Host":[
                "app.mitgedanken.eu"
            ],
            "Accept-Language":[
                "en-GB,en-US;q=0.9,en;q=0.8,de-DE;q=0.7,de;q=0.6"
            ],
            "Priority":[
                "u=1, i"
            ],
            "Dnt":[
                "1"
            ],
            "Sec-Ch-Ua-Platform":[
                "\"Windows\""
            ]
        }
    },
    "bytes_read":0,
    "user_id":"",
    "duration":0.000029183,
    "size":0,
    "status":0,
    "resp_headers":{
        "Server":[
            "FrankenPHP Caddy"
        ]
    }
}

[dunglas]

This is expected behavior, not a bug in the example.

The state-persistence snippet works correctly when the script actually runs in worker mode: each request returns 1, 2, 3, ... with status 200. I verified it against PHP 8.6 ZTS.

A blank page means the script is being executed outside worker mode (the worker directive is missing, or the requested path is not routed to your worker script). In that case frankenphp_handle_request() throws:

Uncaught RuntimeException: frankenphp_handle_request() called while not in worker mode

With the production default display_errors=Off, that fatal is hidden and you get an empty response (HTTP 500), i.e. the blank page you're seeing. The error is written to the logs at err level, which is why the "Relevant log output" section would show it.

To fix your setup, make sure the worker is configured, e.g.:

frankenphp {
    worker ./public/index.php
}

or via the environment variable:

FRANKENPHP_CONFIG="worker ./public/index.php"

See https://frankenphp.dev/docs/worker/ for the full setup.

If you have the worker directive configured and still get a blank page, please reopen with your Caddyfile / FRANKENPHP_CONFIG and the server logs (the log output section was empty). Closing for now.

[sa-tasche]

Caddy

{
	admin localhost:2019

	log {
		output file /var/log/caddy/access.log
	}
}

mitgedanken.eu {
	root * /srv/http
	file_server
}

app.mitgedanken.eu {
	reverse_proxy http://127.0.0.1:9000
}

Frankenphp

{
	admin off #127.0.0.1:2020
	auto_https off

	frankenphp
}

http://127.0.0.1:9000 {
	log {
		output file /var/log/frankenphp/access.log
	}
	
	php_server {
		root /srv/php
		worker {
			file /srv/worker/worker.php
			num 4
			watch
		}
	}
}

Log

{
    "level": "info",
    "ts": 1784557298.5655265,
    "logger": "http.log.access",
    "msg": "NOP",
    "request": {
        "remote_ip": "127.0.0.1",
        "remote_port": "45762",
        "client_ip": "127.0.0.1",
        "proto": "HTTP/1.1",
        "method": "GET",
        "host": "app.mitgedanken.eu",
        "uri": "/favicon.ico",
        "headers": {
            "Referer": [
                "https://app.mitgedanken.eu/"
            ],
            "Sec-Fetch-Dest": [
                "image"
            ],
            "Sec-Ch-Ua": [
                "\"Not;A=Brand\";v=\"8\", \"Chromium\";v=\"150\", \"Microsoft Edge\";v=\"150\""
            ],
            "Accept-Encoding": [
                "gzip, deflate, br, zstd"
            ],
            "User-Agent": [
                "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.0.0 Safari/537.36 Edg/150.0.0.0"
            ],
            "Sec-Fetch-Mode": [
                "no-cors"
            ],
            "Via": [
                "3.0 Caddy"
            ],
            "X-Forwarded-For": [
                "46.83.242.243"
            ],
            "X-Forwarded-Proto": [
                "https"
            ],
            "Accept": [
                "image/avif,image/webp,image/apng,image/svg+xml,image/*,*/*;q=0.8"
            ],
            "Sec-Ch-Ua-Mobile": [
                "?0"
            ],
            "Sec-Fetch-Site": [
                "same-origin"
            ],
            "X-Forwarded-Host": [
                "app.mitgedanken.eu"
            ],
            "Accept-Language": [
                "en-GB,en-US;q=0.9,en;q=0.8,de-DE;q=0.7,de;q=0.6"
            ],
            "Priority": [
                "u=1, i"
            ],
            "Dnt": [
                "1"
            ],
            "Sec-Ch-Ua-Platform": [
                "\"Windows\""
            ]
        }
    },
    "bytes_read": 0,
    "user_id": "",
    "duration": 0.000029183,
    "size": 0,
    "status": 0,
    "resp_headers": {
        "Server": [
            "FrankenPHP Caddy"
        ]
    }
}