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dockerphp-pm

PHP-PM Container does not answer request from different Docker container

I have a simple docker-compose setup with a nginx proxy and a container running PHP-PM:

version: "3.5"

services:
    proxy:
        image: nginx
        depends_on:
            - php_pm
    php_pm:
        build: .

The Dockerfile for php_pm is modified from https://github.com/php-pm/php-pm-docker/blob/master/build/Dockerfile-standalone to use PHP 8.1:

FROM composer as composer

ARG version=2.4.0
ARG http_version=dev-master
RUN docker-php-ext-install -j$(nproc) pcntl
RUN mkdir /ppm && cd /ppm && composer require php-pm/php-pm:${version} && composer require php-pm/httpkernel-adapter:${http_version}

FROM php:8.1

RUN apt update && apt install -y git libicu-dev libpng-dev libzip-dev procps xmlsec1 zip zlib1g-dev
RUN docker-php-ext-install -j$(nproc) gd intl mysqli opcache pcntl pdo_mysql zip

EXPOSE 81

COPY --from=composer /ppm /ppm

WORKDIR /var/www

ENTRYPOINT ["/ppm/vendor/bin/ppm", \
    "start", \
    "--static-directory=public/", \
    "--app-env=dev", \
    "--port=81", \
    "--socket-path=/ppm/run", \
    "--pidfile=/ppm/ppm.pid", \
    "--debug=1"]

Now if I exec into the php_pm container and use curl localhost:81 I get a response from PHP-PM (I think that is what the header Server: ReactPHP/1 is).

Now my problem: When I exec into the container proxy and try to curl the php_pm container i get this:

curl php_pm:81
curl: (7) Failed to connect to php_pm port 81: Connection refused

Why is PHP-PM answering on port 81 when I'm inside the php_pm container, but not when I am in the proxy container? Usually this is not an issue, with e.g. nginx and another container running pm2. Does PHP-PM not fully reserver port 81 inside the network defined by my docker-compose.yaml file?

Solution

  • You must set --host=0.0.0.0 on your ENTRYPOINT, otherwise process in container will listen on 127.0.0.1:81 (ie. localhost:81) by default and will only be reachable from within this same container.

    ENTRYPOINT ["/ppm/vendor/bin/ppm", \
    "start", \
    "--static-directory=public/", \
    "--app-env=dev", \
    "--host=0.0.0.0", \
    "--port=81", \
    "--socket-path=/ppm/run", \
    "--pidfile=/ppm/ppm.pid", \
    "--debug=1"]

    When you curl from within php_pm container it works because you're reaching the server from localhost, but curl from another container won't work as you're trying to reach the server from a different host. Using 0.0.0.0:81 will allow you to reach server from another container.