posgresをDockerで動かしたい

#環境
Mac os Catalina -v10.15.4
Ruby Mine
#やりたいこと
RailsのAPIをDockerでpostgresを動かしながら作成しようとしています
docker-compose.ymlは以下のようになります。

version: '3'
services:
  db:
    image: postgres:12.2
    environment:
      - DATABASE_HOST=localhost
      - POSTGRES_USER=$API_DB_DEV_USERNAME
      - POSTGRES_PASSWORD=$API_DB_DEV_PASSWORD
      - PGPASSWORD=$API_DB_DEV_PASSWORD
    ports:
      - "5432:5432"
    volumes:
      - datavol:/var/lib/postgresql/data
volumes:
  datavol:

追記(04/12/18:37)
database.yamlは以下のようになります

# PostgreSQL. Versions 9.3 and up are supported.
#
# Install the pg driver:
#   gem install pg
# On macOS with Homebrew:
#   gem install pg -- --with-pg-config=/usr/local/bin/pg_config
# On macOS with MacPorts:
#   gem install pg -- --with-pg-config=/opt/local/lib/postgresql84/bin/pg_config
# On Windows:
#   gem install pg
#       Choose the win32 build.
#       Install PostgreSQL and put its /bin directory on your path.
#
# Configure Using Gemfile
# gem 'pg'
#
default: &default
  adapter: postgresql
  encoding: unicode
  # For details on connection pooling, see Rails configuration guide
  # https://guides.rubyonrails.org/configuring.html#database-pooling
  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>

development:
  <<: *default
  database: bokin_back_development

  # The specified database role being used to connect to postgres.
  # To create additional roles in postgres see `$ createuser --help`.
  # When left blank, postgres will use the default role. This is
  # the same name as the operating system user that initialized the database.
  #username: bokin_back

  # The password associated with the postgres role (username).
  #password:

  # Connect on a TCP socket. Omitted by default since the client uses a
  # domain socket that doesn't need configuration. Windows does not have
  # domain sockets, so uncomment these lines.
  #host: localhost

  # The TCP port the server listens on. Defaults to 5432.
  # If your server runs on a different port number, change accordingly.
  #port: 5432

  # Schema search path. The server defaults to $user,public
  #schema_search_path: myapp,sharedapp,public

  # Minimum log levels, in increasing order:
  #   debug5, debug4, debug3, debug2, debug1,
  #   log, notice, warning, error, fatal, and panic
  # Defaults to warning.
  #min_messages: notice

# Warning: The database defined as "test" will be erased and
# re-generated from your development database when you run "rake".
# Do not set this db to the same as development or production.
test:
  <<: *default
  database: bokin_back_test

# As with config/credentials.yml, you never want to store sensitive information,
# like your database password, in your source code. If your source code is
# ever seen by anyone, they now have access to your database.
#
# Instead, provide the password as a unix environment variable when you boot
# the app. Read https://guides.rubyonrails.org/configuring.html#configuring-a-database
# for a full rundown on how to provide these environment variables in a
# production deployment.
#
# On Heroku and other platform providers, you may have a full connection URL
# available as an environment variable. For example:
#
#   DATABASE_URL="postgres://myuser:mypass@localhost/somedatabase"
#
# You can use this database configuration with:
#
#   production:
#     url: <%= ENV['DATABASE_URL'] %>
#
production:
  <<: *default
  database: bokin_back_production
  username: bokin_back
  password: <%= ENV['BOKIN_BACK_DATABASE_PASSWORD'] %>

zshの環境変数にはPOSGRES_USERとPOSGRES_PASSWORDを記述しました.

開発ディレクトリにて、docker-compose up -dを実行して
rails db:migrateを実行したのですがエラーが出て、困っています

#エラー
rails db:migrateを実行したログがこちらです。

user@ts21-2 app_back % rails db:migrate
Warning: the running version of Bundler (2.1.2) is older than the version that created the lockfile (2.1.4). We suggest you to upgrade to the version that created the lockfile by running `gem install bundler:2.1.4`.
/Users/ts/.rbenv/versions/2.7.0/lib/ruby/gems/2.7.0/gems/actionpack-6.0.2.2/lib/action_dispatch/middleware/stack.rb:37: warning: Using the last argument as keyword parameters is deprecated; maybe ** should be added to the call
/Users/ts/.rbenv/versions/2.7.0/lib/ruby/gems/2.7.0/gems/actionpack-6.0.2.2/lib/action_dispatch/middleware/static.rb:110: warning: The called method `initialize' is defined here
/Users/ts/.rbenv/versions/2.7.0/lib/ruby/gems/2.7.0/gems/activerecord-6.0.2.2/lib/active_record/type.rb:27: warning: Using the last argument as keyword parameters is deprecated; maybe ** should be added to the call
/Users/ts/.rbenv/versions/2.7.0/lib/ruby/gems/2.7.0/gems/activerecord-6.0.2.2/lib/active_record/type/adapter_specific_registry.rb:9: warning: The called method `add_modifier' is defined here
rails aborted!
PG::ConnectionBad: could not connect to server: No such file or directory
        Is the server running locally and accepting
        connections on Unix domain socket "/tmp/.s.PGSQL.5432"?
/Users/ts/RubymineProjects/app_back/bin/rails:9:in `<top (required)>'
/Users/ts/RubymineProjects/app_back/bin/spring:15:in `<top (required)>'
bin/rails:3:in `load'
bin/rails:3:in `<main>'
Tasks: TOP => db:migrate
(See full trace by running task with --trace)

posgresのサーバに接続していないのが原因のようです
直接関係ないとbundlerのバージョンは2.1.4のはずですがwarningがでてました

ts@ts21-2 app_back % bundler -v      
Bundler version 2.1.4

#やったこと
同じエラーの記事を参考に
$ brew services start postgresqlと再起動を実行した上で、再びrails db:migrate
しましたが、上記エラーがでました

(そもそも、これはDockerと関係あるのか?)
#憶測
Dockerを立てて posgreを使うのが今回初めてなので、もしかするとDockerの設定に間違いがあるのか
と思っています。

hoshi-takanori

2020/04/12 09:31

config/database.yml の設定はどうなってますか？あと、docker とは別に brew でも postgresql を動かしてますか？

ts21

2020/04/12 09:37

config/database.ymを追記いたしました。 brew でも postgresql を動かしていました。

行動規範の内容に同意します

回答1件

ベストアンサー

このエラーが出るのは、pgsql などのクライアントから PostgreSQL にソケット接続を試みて失敗しています。

PG::ConnectionBad: could not connect to server: No such file or directory
        Is the server running locally and accepting
        connections on Unix domain socket "/tmp/.s.PGSQL.5432"?

今回の記述では、Docker Compose でポート 5432 を開いていますので、クライアント側からは TCP を通して、自分自身（ localhost または 127.0.0.1 の）ポート 5432 に接続する必要があります。

確認手順としては、まず、クライアント側から psql -h 127.0.0.1 -p 5432 -U ユーザ名 を接続して、接続できるかどうかの確認です。

もしここで接続できなければ、PostgreSQL （コンテナ）側の設定確認が必要です。 docker-compose ps で db サービスが起動しているかどうか確認します。もし停止していれば起動します。

次に database.yaml は初期状態に近いようですが、これをホスト 127.0.0.1 に、ポート 5432 で接続するように記述を変えると動作するでしょう。

投稿2021/04/10 22:00