可以从 docker 容器外部连接到数据库，但不能从内部连接到数据库（在 laravel 中）

Question

I refactored this question due to the down votes.

It comes as simple as this:

Outside docker container:

➜  backoffice git:(master) ✗ php artisan tinker
Psy Shell v0.9.9 (PHP 7.2.15 — cli) by Justin Hileman
>>> $ur = app(MDiPaolo\Repositories\UserRepository::class)
=> App\Infrastructure\Repositories\Doctrine\UserDoctrineRepository {#3159}
>>> $u = new MDiPaolo\Entities\User
=> MDiPaolo\Entities\User {#3295}
>>> $u->setEmail('one_email@gmail.com')
=> MDiPaolo\Entities\User {#3295}
>>> $u->setPassword(password_hash('1234', PASSWORD_BCRYPT))
=> null
>>> $ur->save($u)
=> null
>>>

Inside docker container:

➜  backoffice git:(master) ✗ docker exec -it backoffice_web_1 bash
root@042969f0229c:/var/www/html# php artisan tinker
Psy Shell v0.9.9 (PHP 7.2.17 — cli) by Justin Hileman
>>> $ur = app(MDiPaolo\Repositories\UserRepository::class)
Doctrine/DBAL/Exception/ConnectionException with message 'An exception occurred in driver: SQLSTATE[HY000] [2002] Connection refused'
>>>

I have the feeling it is related with the docker system, say the communication between both containers or how i built them.

This is my Dockerfile.

FROM php:7.2-apache

RUN docker-php-ext-install pdo_mysql && docker-php-ext-enable pdo_mysql
RUN apt-get update && apt-get install nano && mv "$PHP_INI_DIR/php.ini-development" "$PHP_INI_DIR/php.ini"

RUN a2enmod rewrite
RUN service apache2 restart

ENV APACHE_DOCUMENT_ROOT=/var/www/html/public
RUN sed -ri -e 's!/var/www/html!${APACHE_DOCUMENT_ROOT}!g' /etc/apache2/sites-available/*.conf
RUN sed -ri -e 's!/var/www/!${APACHE_DOCUMENT_ROOT}!g' /etc/apache2/apache2.conf /etc/apache2/conf-available/*.conf

docker-compose file:

version: '3.1'

services:
    web:
        build: .
        ports:
            - "8080:80"
        links:
            - mysql
        depends_on:
            - mysql
        volumes:
            - ./:/var/www/html
    mysql:
        image: mysql:5.7.25
        ports:
            - "3306:3306"
        environment:
            MYSQL_ROOT_PASSWORD: backoffice

Answer 1

Ok i found the solution.

IN the .env file the DB_HOST field has to be equal to the name of mysql container in the docker-compose.yml file, in my case mysql .

DB_CONNECTION=mysql
DB_HOST=mysql
DB_PORT=3306
DB_DATABASE=dashboard
DB_USERNAME=root
DB_PASSWORD=backoffice

Problem would be that now i cannot access it from the outside, but of course you can always go:

127.0.0.1    mysql

at your hosts file