Replace the rack-livereload gem with own middleware

This also patches livereload to only reload the page if it changed. (When changing a layout nanoc can send dozens of URLs for changed pages, this ensures we only reload once.)

Co-authored-by: Jan M. Faber <[email protected]>
Co-authored-by: Denis Defreyne <[email protected]>

README.md

@@ -87,6 +87,7 @@ It takes the following options:
 ## Contributors
 
 - Ed Brannin
+- Jan M. Faber
 - Larissa Reis
 - Mark Meves
 - Vipul Amler

adsf-live/Rakefile

@@ -6,7 +6,6 @@ Rake::TestTask.new(:test) do |t|
   t.test_files = Dir[__dir__ + '/test/**/test_*.rb']
   t.libs << 'test'
   t.verbose = false
-  t.warning = false # TODO: turn this back on when rack-livereload is fixed
 end
 
 task :gem do

adsf-live/adsf-live.gemspec

@@ -20,7 +20,6 @@ Gem::Specification.new do |s|
   s.add_dependency('em-websocket', '~> 0.5')
   s.add_dependency('eventmachine', '~> 1.2')
   s.add_dependency('listen', '~> 3.0')
-  s.add_dependency('rack-livereload', '~> 0.3')
 
   s.files                 = ['NEWS.md', 'README.md'] + Dir['lib/**/*.rb']
   s.require_path          = 'lib'

adsf-live/adsf-live.manifest

@@ -3,5 +3,6 @@ README.md
 
 lib/adsf/live.rb
 lib/adsf/live/version.rb
+lib/adsf/live/rack_livereload.rb
 lib/adsf/live/watcher.rb
 lib/adsf/live/web_socket_server.rb

adsf-live/lib/adsf/live.rb

@@ -5,13 +5,13 @@
 require 'em-websocket'
 require 'json'
 require 'listen'
-require 'rack-livereload'
 
 module Adsf
   module Live
   end
 end
 
 require_relative 'live/version'
+require_relative 'live/rack_livereload'
 require_relative 'live/web_socket_server'
 require_relative 'live/watcher'

adsf-live/lib/adsf/live/rack_livereload.rb

@@ -0,0 +1,74 @@
+# frozen_string_literal: true
+
+module Rack
+  class LiveReload
+    LIVERELOAD_JS_PATH = '/__rack/livereload.js'
+    VENDORED_JS_PATH = "#{__dir__}/../../../vendor/livereload.js"
+    HEAD_TAG_REGEX = /<head( [^<]+)?>/.freeze
+    LIVERELOAD_PORT = 35_729
+    LIVERELOAD_SCHEME = 'ws'
+
+    def initialize(app, options = {})
+      @app = app
+      @options = options
+    end
+
+    def call(env)
+      return deliver_file(VENDORED_JS_PATH) if env['PATH_INFO']&.end_with? LIVERELOAD_JS_PATH
+
+      status, headers, body = result = @app.call(env)
+
+      if env['REQUEST_METHOD'] != 'GET' ||
+         headers['content-type'] !~ %r{text/html} ||
+         headers['transfer-encoding'] == 'chunked' ||
+         headers['content-disposition'] =~ /^inline/
+        return result
+      end
+
+      body.close if body.respond_to?(:close)
+      new_body = []
+      livereload_added = false
+      @env = env
+      body.each do |line|
+        if !livereload_added && line =~ HEAD_TAG_REGEX
+          new_body << line.sub(HEAD_TAG_REGEX) { |match| %(#{match}#{template}) }
+          livereload_added = true
+        else
+          new_body << line
+        end
+      end
+      headers['content-length'] = new_body.sum(&:bytesize).to_s
+      headers['x-rack-livereload'] = '1' if livereload_added
+
+      [status, headers, new_body]
+    end
+
+    private
+
+    def deliver_file(file)
+      [200, { 'content-type' => 'text/javascript', 'content-length' => ::File.size(file).to_s }, [::File.read(file)]]
+    end
+
+    def template
+      <<~HTML
+        <script>
+          RACK_LIVERELOAD_PORT = #{@options[:live_reload_port] || LIVERELOAD_PORT}
+          RACK_LIVERELOAD_SCHEME = "#{@options[:live_reload_scheme] || LIVERELOAD_SCHEME}"
+        </script>
+        <script src="#{livereload_source}?host=#{host_to_use}"></script>
+      HTML
+    end
+
+    def livereload_source
+      if @options[:source] == :vendored
+        LIVERELOAD_JS_PATH
+      else
+        "#{@options[:protocol] || 'http'}://#{host_to_use}/livereload.js"
+      end
+    end
+
+    def host_to_use
+      (@options[:host] || @env['HTTP_HOST'] || 'localhost').sub(/:.*/, '')
+    end
+  end
+end

adsf-live/lib/adsf/live/web_socket_server.rb

@@ -23,7 +23,7 @@ def reload(paths)
           data =
             JSON.dump(
               command: 'reload',
-              path: "#{Dir.pwd}#{path}",
+              path: path,
             )
 
           @sockets.each { |ws| ws.send(data) }

adsf-live/test/test_watcher.rb

@@ -78,7 +78,7 @@ def test_receives_update
       assert_equal expected_hello_data, JSON.parse(messages[0])
 
       assert_equal 'reload', JSON.parse(messages[1])['command']
-      assert_match %r{adsf(-live)?/tmp/index\.html$}, JSON.parse(messages[1])['path']
+      assert_equal '/index.html', JSON.parse(messages[1])['path']
     end
   end
 end