cURL between Docker service php-fpm containers results in "Connection refused" - php

Question

after looking for an answer 2 weeks along, going deep into the docker compose and docker networks documentations, I'd like to ask for some help right here.
I am creating two Web API services, let's called them a back API (back.api.dev) and a front API (front.api.dev).
What I tried so far :
The back API is connected to a MySQL database, and the front API only sends cURL requests to the back API. Both APIs are built upon Symfony and are processed by a docker PHP-FPM container. Everything is served by a docker Apache 2.4 container.
Sending requests through Postman and cURL requests to back.api.dev & front.api.dev are both working great. It works both from my host, but also from the Apache container. I also added 127.0.0.1 back.api.dev and 127.0.0.1 front.api.dev to my /etc/hosts host machine file. The back API is well connected to the database as well.
But when I send a request to a specific front API route which runs a cURL request to the back API using GuzzleHTTP client and send the answer back to the user, I get a cURL error 7: Failed to connect to back.api.dev port 80: Connection refused (see https://curl.haxx.se/libcurl/c/libcurl-errors.html) for http://back.api.dev/api/videos/
I also tried to send cURL requests from the CLI inside the front_api container but the result is the same. I also tried to send it directly to the port 9000 handled by php-fpm but I get a cURL error 56: Recv failure: Connection reset by peer error.
Here's the docker-compose.yml file :
version: "3.8"
networks:
my_api_network:
driver: bridge
# external:
# name: my_api_network_default
services:
apache:
container_name: 'api_apache'
image: bitnami/apache:latest
ports:
- 8080:8080
# - 8443:8443
volumes:
- ./docker/apache/vhosts/back-api-dev.conf:/vhosts/back-api-dev.conf:ro
- ./docker/apache/vhosts/front-api-dev.conf:/vhosts/front-api-dev.conf:ro
volumes_from:
- php_backend_api
- php_frontend_api
depends_on:
- php_backend_api
- php_frontend_api
networks:
- my_api_network
php_backend_api:
hostname: 'back.api.dev'
container_name: 'php_backend_api'
build:
context: docker/php7-fpm
network: host
args:
TIMEZONE: 'UTC'
volumes:
- ./docker/php7-fpm/php.ini:/usr/local/etc/php/php.ini:ro
- ./back_api/:/var/www/back_api:cached
- ./back_api/vendor:/var/www/back_api/vendor:delegated
- /var/www/back_api/var/
networks:
- my_api_network
php_frontend_api:
hostname: 'front.api.dev'
container_name: 'php_frontend_api'
build:
context: docker/php7-fpm
network: host
args:
TIMEZONE: 'UTC'
volumes:
- ./docker/php7-fpm/php.ini:/usr/local/etc/php/php.ini:ro
- ./front_api/:/var/www/front_api:cached
- ./front_api/vendor:/var/www/front_api/vendor:delegated
- /var/www/front_api/var/
networks:
- my_api_network
db:
container_name: 'mysql_db'
image: mysql:5.7
restart: always
volumes:
- ./docker/data/mysql:/var/lib/mysql:delegated
- ./docker/mysql:/etc/mysql/conf.d:ro
environment:
MYSQL_ROOT_PASSWORD: ${MYSQL_ROOT_PASSWORD}
TZ: ${TIMEZONE}
command: --sql_mode="STRICT_ALL_TABLES,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER" --default-authentication-plugin=mysql_native_password
ports:
- 3306:3306
networks:
- my_api_network
Here is my back API Apache Virtualhost :
<VirtualHost *:8080>
ServerName back.api.dev
DocumentRoot "/var/www/back_api/public"
ProxyPassMatch ^/(.*\.php(/.*)?)$ fcgi://php_backend_api:9000/var/www/back_api/public/$1
<Directory "/var/www/back_api/public">
Options Indexes FollowSymLinks
AllowOverride All
Require all granted
DirectoryIndex index.php
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^ index.php [QSA,L]
</IfModule>
</Directory>
LogLevel debug
# LogLevel warn
# LogLevel notice
ErrorLog /opt/bitnami/apache2/logs/error-back.log
CustomLog /opt/bitnami/apache2/logs/access-back.log combined
</VirtualHost>
My guess is that Apache is not enough configured to forward incoming curl requests to the php-fpm instance. I looked after Docker networks, aliases, drivers, extra_hosts but nothing has helped so far to fix this issue.
Thank you for your help.

Answer 1

I'm thinking that there's no url http://back.api.dev/api/videos/ from the front end.
maybe it needs a host entry in the front end like you've done on your host box.
sorry I don't have enough points to put this in as a suggestion comment rather than an answer.