私は、herokuとローカルマシンの両方で機能するこの機能をなんとか組み合わせて、データベースが存在しない場合はデータベースを作成します。
# ./lib/db_connect.rb
require 'erb'
require 'uri'
require 'em-synchrony/activerecord'
class DbConnect
attr_accessor :config
def initialize
@db = URI.parse(ENV['DATABASE_URL'] || 'http://localhost')
if @db.scheme == 'postgres' # This section makes Heroku work
ActiveRecord::Base.establish_connection(
:adapter => @db.scheme == 'postgres' ? 'postgresql' : @db.scheme,
:host => @db.host,
:username => @db.user,
:password => @db.password,
:database => @db.path[1..-1],
:encoding => 'utf8'
)
else # And this is for my local environment
environment = ENV['DATABASE_URL'] ? 'production' : 'development'
@db = YAML.load(ERB.new(File.read('config/database.yml')).result)[environment]
ActiveRecord::Base.establish_connection(@db)
@config = ActiveRecord::Base.connection.pool.spec.config
end
end
end
# connect to the database
DbConnect.new
そして、これを使用するRakefileがあります。
# ./Rakefile
$: << './lib'
require 'db_connect'
db = DbConnect.new
config = db.config
desc 'create the database'
task :create_db do
unless ENV['DATABASE_URL'].present?
ActiveRecord::Base.establish_connection adapter:'postgresql',username:config[:username],password:config[:password], database: 'postgres'
ActiveRecord::Base.connection.create_database config[:database]
else
raise StandardError, "You cannot do this on Heroku!"
end
end
desc 'create the users table'
task :create_users_table do
ActiveRecord::Schema.define(:version => 0) do
create_table "users", :force => true do |t|
t.string "first_name"
t.string "last_name"
t.datetime "created_at", :null => false
t.datetime "updated_at", :null => false
end
end
end
問題が解決しました。