Added docker compose file to make bringing up/down the services easier; modified puma config to be more efficient

config/puma.rb

@@ -1,11 +1,28 @@
 app_dir = File.expand_path('..', __dir__)
 directory app_dir
 
+# load puma config from environment variables
 environment ENV.fetch('RACK_ENV', 'development')
 
-require_relative '../src/config'
-conf = Config.new()
+# listening address
+host = ENV.fetch('BIND_HOST', '0.0.0.0')
+port = ENV.fetch('PORT', 9292)
+bind "tcp://#{host}:#{port}"
 
-bind "tcp://#{conf.get('server.host')}:#{conf.get('server.port')}"
-workers 2
-threads 1, 5
+# Concurrency tuning
+workers_count = ENV.fetch('WEB_CONCURRENCY', 2).to_i
+workers workers_count
+
+max_threads_count = ENV.fetch('PUMA_MAX_THREADS', ENV.fetch('RAILS_MAX_THREADS', 5)).to_i
+min_threads_count = ENV.fetch('PUMA_MIN_THREADS', ENV.fetch('RAILS_MIN_THREADS', 1)).to_i
+threads min_threads_count, max_threads_count
+
+# Preload app code before forking worker processes for better memory usage (Copy-on-Write)
+if workers_count > 0
+	preload_app!
+
+	before_fork do
+    # Disconnect Sequel connection pool in the master process before forking
+    DB.disconnect if defined?(DB)
+  end
+end