$ curl localhost:3000
curl: (7) Failed to connect to localhost port 3000: Connection refused

version: "3"

services:
  web:
    build: web
    ports:
      - "3000:3000"
    environment:
      - "DATABASE_HOST=db"
      - "DATABASE_PORT=5432"
      - "DATABASE_USER=＊＊＊＊＊＊＊＊"
      - "DATABASE_PASSWORD=＊＊＊＊＊＊＊＊"
    links:
      - db
    volumes:
      - "./app:/app" #共有フォルダの設定
    stdin_open: true

  db:
    image: postgres:10.1
    ports:
      - "5432:5432"
    environment:
      - "POSTGRES_USER=＊＊＊＊＊＊＊＊"
      - "POSTGRES_PASSWORD=＊＊＊＊＊＊＊＊"

FROM ruby:2.5.0

RUN apt-get update && apt-get install -y build-essential libpq-dev postgresql-client
RUN gem install rails
RUN mkdir /app
WORKDIR /app