sinatra and datamapper

Gemfile.rb

# Gemfile

source "https://rubygems.org"

gem "sinatra"
gem "data_mapper"
gem "dm-postgres-adapter"
gem "pg"

group :test do
  ...
  gem "sqlite3"
  gem "dm-sqlite-adapter"
end

init.rb

require 'sinatra'
require 'data_mapper'

DataMapper.setup(:default, ENV['DATABASE_URL'] || 'postgres://localhost/myblog')

class Post
  include DataMapper::Resource

  property :id, Serial
  property :title, String, :required => true
  property :body, Text, :required => true
  property :created_at, DateTime, :required => true
end
DataMapper.finalize.auto_upgrade!
...

spec_helper.rb

require 'sinatra'
require 'bundler'
Bundler.require(:test)

RSpec.configure do |c|
  c.include Rack::Test::Methods
  DataMapper::setup(:default, "sqlite3://#{Dir.pwd}/db/post_test.db")
  DataMapper.finalize
  Post.auto_migrate!
end