XDebug 3 and Docker Reference

README.md

XDEBUG 3 Configuration with Docker and PhpStorm

XDebug 3 only started working out of the box with PhpStorm version 2020.3

Reference article - Configure Xdebug

The list of changes from XDebug 2 to 3 are available here for reference - Upgrade Guide

Configuring PhpStorm

Go to PhpStorm -> Settings -> Languages & Frameworks -> PHP -> Servers

1. Click "+"
2. Name docker-cli (Same as serverName under PHP_IDE_CONFIG environment variable)
3. Host _
4. Default 80
5. Debugger Xdebug
6. Check the checkbox next to "Use path mappings"
7. Modify the absolute path on the server to /var/www/html

Running the CLI Command

1. Add breakpoints file
2. In PhpStorm click the icon to "Start Listening for PHP Debug connections"
3. Run in the docker file - docker-compose run php-container php test.php

Troubleshooting

1. Check firewall or selinux if on linux
2. The configuration host.docker.internal only became available under Mac and Windows with Docker version 20.04

docker-compose.yaml

version: '3.8'

services:
    php-container:
        build:
            context: .
            dockerfile: ./docker/Dockerfile
        volumes:
            - .:/var/www/html
            - ./docker/xdebug.ini:/usr/local/etc/php/conf.d/docker-php-ext-xdebug.ini
            - ./docker/php.ini:/usr/local/etc/php/conf.d/custom.ini
        environment:
            PHP_IDE_CONFIG: "serverName=docker-cli"

Dockerfile

FROM php:7.4-cli-alpine

# Install xdebug
RUN apk add --no-cache --virtual .phpize-deps $PHPIZE_DEPS \
  && pecl install xdebug \
  && docker-php-ext-enable xdebug \
  && apk del .phpize-deps

WORKDIR /var/www/html

xdebug.ini

[XDebug]
zend_extension=xdebug.so

xdebug.mode = debug
xdebug.start_with_request=yes

#Replace host.docker.internal to your computers IP address if linux
xdebug.client_host=host.docker.internal

#Replace host.docker.internal to your computers IP address if linux
xdebug.client_host=host.docker.internal

On linux since docker 20.04 you can set:

extra_hosts:
  - "host.docker.internal:host-gateway"

🎉

https://stackoverflow.com/questions/31324981/how-to-access-host-port-from-docker-container/43541732#43541732

@Raistlfiren Hi, does this work on requests from browser? Thanks for sharing!

@WonRhee Install the „Xdebug Helper“ browser extension and configure it with the settings for your IDE.
The extension will set the request params for you to enable or disable php debugging.