Add class Diversipub::SinatraApp

diversipub.gemspec

@@ -41,6 +41,8 @@ Gem::Specification.new do |spec|
 
   spec.executables = spec.files.grep(%r{\Aexe/}) { |f| File.basename f }
 
+  spec.add_runtime_dependency 'sinatra', '~> 3.0', '>= 3.0.6'
+
   spec.add_development_dependency 'pry',  '~> 0.14'
   spec.add_development_dependency 'rake', '~> 13.0'
 end

lib/diversipub.rb

@@ -1,4 +1,7 @@
 # frozen_string_literal: true
 
+require 'sinatra/base'
+
 require_relative 'diversipub/main'
+require_relative 'diversipub/sinatra_app'
 require_relative 'diversipub/version'

lib/diversipub/sinatra_app.rb

@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+module Diversipub
+  ##
+  # Sinatra web application.
+  #
+  class SinatraApp < Sinatra::Base
+    set :environment, :production
+    set :root, File.expand_path('../..', __dir__).freeze
+    set :views, nil
+    set :public_folder, nil
+
+    def initialize(main)
+      super()
+      @main = main
+    end
+
+    class << self
+      # Disable default Sinatra servers & middleware.
+      alias new new!
+    end
+  end
+end