Allow skipping master key

lib/mrsk/commands/app.rb

@@ -98,6 +98,10 @@ class Mrsk::Commands::App < Mrsk::Commands::Base
     end
 
     def rails_master_key_arg
-      [ "-e", redact("RAILS_MASTER_KEY=#{config.master_key}") ]
+      if master_key = config.master_key
+        [ "-e", redact("RAILS_MASTER_KEY=#{master_key}") ]
+      else
+        []
+      end
     end
 end

lib/mrsk/configuration.rb

@@ -115,7 +115,9 @@ class Mrsk::Configuration
   end
 
   def master_key
-    ENV["RAILS_MASTER_KEY"] || File.read(Pathname.new(File.expand_path("config/master.key")))
+    unless raw_config.skip_master_key
+      ENV["RAILS_MASTER_KEY"] || File.read(Pathname.new(File.expand_path("config/master.key")))
+    end
   end
 
   def to_h