Dockerized Rails / Postgres应用程序中的数据库身份验证失败

Question

我正在尝试使用docker-compose运行Rails / Postgres应用，但是在不设置POSTGRES_HOST_AUTH_METHOD="trust"的情况下创建数据库时遇到了麻烦。以下docker-compose.yml在“信任”下似乎可以正常工作：

version: '3'
services:
  db:
    image: postgres:alpine
    env_file: .env
    environment:
      POSTGRES_HOST_AUTH_METHOD: "trust"
    volumes:
      - ./tmp/db:/var/lib/postgresql/data
  web:
    build:
      context: .
      dockerfile: Dockerfile
    command: bundle exec rails server -b '0.0.0.0' -p 3000
    env_file: .env
    ports:
      - "3000:3000"
    volumes:
      - .:/app
      - node_modules:/app/node_modules/
    depends_on:
      - db
volumes:
  node_modules:

为了使此工作不带“信任”，我理解在初始化Postgres图像以设置默认用户密码时，必须定义环境变量POSTGRES_PASSWORD。因此，我们使用以下.env文件，已由docker-compose引用：

POSTGRES_URL=db
POSTGRES_PASSWORD=foobar

并更改config / database.yml以使用以下默认连接配置：

...

default: &default
  adapter: postgresql
  encoding: unicode
  host: <%= ENV['POSTGRES_URL'] %>
  # If POSTGRES_PASSWORD is set in the environment then use the default user
  # and that password to connect. If none is set, then assume that the creds
  # are elsewhere (e.g. included in POSTGRES_URL on Heroku)
  <% if ENV['POSTGRES_PASSWORD'].present? %>
  username: postgres
  password: <%= ENV['POSTGRES_PASSWORD'] %>
  <% end %>
  # For details on connection pooling, see Rails configuration guide
  # https://guides.rubyonrails.org/configuring.html#database-pooling
  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
...

然后我在控制台中执行以下操作：

$ docker-compose build
db uses an image, skipping
Building web
...
$ docker-compose run web echo container started successfully
Starting rails-dockerized_db_1 ... done
container started successfully
$ docker-compose run web bundle exec rails db:create
Starting rails-dockerized_db_1 ... done
FATAL:  password authentication failed for user "postgres"
Couldn't create 'rails_dockerized_development' database. Please check your configuration.
rails aborted!
ActiveRecord::NoDatabaseError: FATAL:  password authentication failed for user "postgres"
...

据我所知，此配置应该正确，但是我显然忽略了某些内容。为什么我看到此身份验证失败？

Answer 1

在您的.env文件中添加POSTGRES_USER=postgres

PostgreSQL需要POSTGRES_USER

https://github.com/x1wins/tutorial-rails-rest-api/blob/master/docker-compose.yml