config/database.yml

default: &default
  adapter: postgresql
  encoding: unicode
  host: <%= ENV["POSTGRES_HOST"] %>
  port: <%= ENV["POSTGRES_PORT"] %>
  database: <%= ENV["POSTGRES_DB"] %>
  username: <%= ENV["POSTGRES_USER"] %>
  password: <%= ENV["POSTGRES_PASSWORD"] %>
  pool: <%= [1, ENV["RAILS_SERVER_PROCESSES"].to_i * ENV["RAILS_MAX_THREADS"].to_i].max %>

development:
  <<: *default

test:
  <<: *default

production:
  <<: *default