Fix using rack v3

README.md

@@ -41,13 +41,13 @@ A minimal rack application using `umbra` would look like this:
 ```ruby
 # /config.ru
 require 'rack'
-require 'rack/lobster'
+require 'rackup/lobster'
 require 'umbra'
 
 Umbra.configure
 
 use Umbra::Middleware
-run Rack::Lobster.new
+run Rackup::Lobster.new
 
 ```
 

ruby/config.ru

@@ -2,12 +2,12 @@ lib = File.expand_path("lib", __dir__)
 $LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
 
 require "rack"
-require "rack/lobster"
+require "rackup/lobster"
 require "puma"
 require "umbra"
 require "pry"
 
 Umbra.configure
 
 use Umbra::Middleware
-run Rack::Lobster.new
+run Rackup::Lobster.new

ruby/lib/umbra/config.rb

@@ -1,3 +1,5 @@
+require "logger"
+
 module Umbra
   class Config
     attr_accessor :publisher, :request_selector, :encoder, :error_handler, :redis_options, :logger

ruby/lib/umbra/version.rb

@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module Umbra
-  VERSION = "0.3.0"
+  VERSION = "0.4.0"
 end

ruby/spec/integration_spec.rb

@@ -7,7 +7,7 @@
     allow(Umbra).to receive(:redis).and_return(redis)
   end
 
-  let(:app) { Rack::Builder.parse_file("config.ru").first }
+  let(:app) { Rack::Builder.parse_file("config.ru") }
   let(:redis) do
     Class.new {
       attr_reader :messages

ruby/umbra-rb.gemspec

@@ -40,5 +40,6 @@ Gem::Specification.new do |spec|
   spec.add_dependency "redis", "~> 4.1"
   spec.add_dependency "google-protobuf", "~> 3"
   spec.add_dependency "rack", ">= 2", "< 4"
+  spec.add_dependency "rackup", ">=2", "< 3"
   spec.add_dependency "zeitwerk", "~> 2"
 end