Ruby on rails docker compose:无法将Rails应用程序连接到Mysql

我正在尝试使用Docker compose和Dockerfile将我的Ruby on Rails应用程序连接到Mariadb数据库，并将数据库（.sql文件）导入该数据库

我使用的是

gem'mysql2'，'>=0.3.18'，'<0.5'

在config/database.yml中，我尝试了：

default: &default
    adapter: mysql2
    encoding: utf8
    pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
    username: root
    password: somepassword
    host: mysql2://root:somepassword@127.0.0.1:3306/mydatabase

development:
    <<: *default

在docker-compose.yml中：

services:
    mysql:
        image: mariadb:10.3
        container_name: mysql
        volumes:
            - ./database.sql:/docker-entrypoint-initdb.d/database.sql
            - ~/.docker-volumes/database/mysql:/var/lib/mysql
        environment:
            MYSQL_ROOT_PASSWORD: somepassword
            MYSQL_DATABASE: mydatabase
        ports:
            - '3306:3306'

    rails_app:
        build: .
        restart: always
        container_name: rails_app
        environment:
            DATABASE_URL: mysql2://root:somepassword@mysql/mydatabase
        links:
            - mysql:sql_srv
            - redis
            - elasticsearch
        volumes:
            - .:/rails_app
         ports:
             - '3000:3000'
         env_file:
             - .rails_app.env

在.rails_app.env中：

SECRET_KEY_BASE=sometoken
WORKER_PROCESSES=1
LISTEN_ON=127.0.0.1:3000
DATABASE_URL=mysql2://root:somepasssword@127.0.0.1:3306/mydatabase

我上次尝试的错误是：

Mysql2::Error: Can't connect to MySQL server on '127.0.0.1' (111 "Connection refused")
...
ERROR: Service 'rails_app' failed to build: The command '/bin/sh -c bundle exec rake RAILS_ENV=production DATABASE_URL=mysql2://root:somepassword@127.0.0.1:3306/mydatabase SECRET_TOKEN=sometoken assets:precompile' returned a non-zero code: 1

如何解决此问题并通过Docker compose成功将rails应用程序与mariadb连接

---

有什么帮助吗？

请尝试将

数据库.yml

更改为

default: &default
    adapter: mysql2
    encoding: utf8
    pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
    username: root
    password: somepassword
    host: sql_srv
    database: mydatabase
    port: 3306

您将传递到数据库服务的

rails\u app

service链接，并将别名设置为

sql\u srv

---

您可以从rails应用程序连接到数据库，使用docker网络中解析的链接连接到

mysql

服务。

尝试两种服务

网络模式：主机

部分什么是sql\u srv？

Mysql2::Error: Can't connect to MySQL server on '127.0.0.1' (111 "Connection refused")
...
ERROR: Service 'rails_app' failed to build: The command '/bin/sh -c bundle exec rake RAILS_ENV=production DATABASE_URL=mysql2://root:somepassword@127.0.0.1:3306/mydatabase SECRET_TOKEN=sometoken assets:precompile' returned a non-zero code: 1

default: &default
    adapter: mysql2
    encoding: utf8
    pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
    username: root
    password: somepassword
    host: sql_srv
    database: mydatabase
    port: 3306

links:
  - mysql:sql_srv
  - redis
  - elasticsearch