Allow role to set env

lib/mrsk/commands/app.rb

@@ -9,7 +9,7 @@ class Mrsk::Commands::App < Mrsk::Commands::Base
       "--restart unless-stopped",
       "--name", config.service_with_version,
       *rails_master_key_arg,
-      *config.env_args,
+      *role.env_args,
       *role.label_args,
       config.absolute_image,
       role.cmd

lib/mrsk/configuration/role.rb

@@ -23,6 +23,14 @@ class Mrsk::Configuration::Role
     argumentize "--label", labels
   end
 
+  def env
+    (config.env || {}).merge(specializations["env"] || {})
+  end
+
+  def env_args
+    argumentize "-e", env
+  end
+
   def cmd
     specializations["cmd"]
   end