Restart the application after each relevant code change

With no lack of code reloading functionality in Sinatra, this I think is
the next-best thing.

There is necessarily downtime after each code change.

Gemfile

@@ -48,6 +48,7 @@ group :test, :development do
 end
 
 group :development do
+  gem 'rerun', require: false
   gem 'rubocop', '0.36.0', require: false
 end
 

Gemfile.lock

@@ -80,6 +80,10 @@ GEM
     kss (0.5.0)
     launchy (2.4.3)
       addressable (~> 2.3)
+    listen (3.1.5)
+      rb-fsevent (~> 0.9, >= 0.9.4)
+      rb-inotify (~> 0.9, >= 0.9.7)
+      ruby_dep (~> 1.2)
     loofah (2.0.3)
       nokogiri (>= 1.5.9)
     metaclass (0.0.4)
@@ -130,13 +134,16 @@ GEM
     rb-readline (0.5.3)
     redcarpet (3.3.4)
     redis (3.3.3)
+    rerun (0.11.0)
+      listen (~> 3.0)
     rouge (2.0.7)
     rubocop (0.36.0)
       parser (>= 2.3.0.0, < 3.0)
       powerpack (~> 0.1)
       rainbow (>= 1.99.1, < 3.0)
       ruby-progressbar (~> 1.7)
     ruby-progressbar (1.8.0)
+    ruby_dep (1.5.0)
     rubypants (0.6.0)
     rubyzip (1.2.1)
     sass (3.4.21)
@@ -215,6 +222,7 @@ DEPENDENCIES
   rake (~> 10.5.0)
   rb-readline
   redcarpet (~> 3.1)
+  rerun
   rouge (~> 2.0.5)
   rubocop (= 0.36.0)
   sass

docker-compose.yml

@@ -6,7 +6,7 @@ services:
       service: app
     links:
       - db
-    command: rackup -s puma -p 4567 --host 0.0.0.0
+    command: rerun -b --ignore='{**/*.{scss,css,js,coffee,erb},test/**}' 'puma -p 4567'
     ports:
       - "${EXTERNAL_PORT}:4567"
     environment: