Catch registry credentials errors nicer

lib/mrsk/cli/registry.rb

@@ -5,10 +5,14 @@ class Mrsk::Cli::Registry < Mrsk::Cli::Base
   def login
     run_locally           { execute *MRSK.registry.login }
     on(MRSK.config.hosts) { execute *MRSK.registry.login }
+  rescue ArgumentError => e
+    puts e.message
   end
 
   desc "logout", "Logout of the registry remotely"
   def logout
     on(MRSK.config.hosts) { execute *MRSK.registry.logout }
+  rescue ArgumentError => e
+    puts e.message
   end
 end

lib/mrsk/configuration.rb

@@ -105,9 +105,13 @@ class Mrsk::Configuration
         raise ArgumentError, "Missing required configuration for #{key}" unless config[key].present?
       end
 
-      %w[ username password ].each do |key|
-        raise ArgumentError, "Missing required configuration for registry/#{key}" unless config.registry[key].present?
+      if config.registry["username"].blank?
+        raise ArgumentError, "You must specify a username for the registry in config/deploy.yml"
       end      
+
+      if config.registry["password"].blank?
+        raise ArgumentError, "You must specify a password for the registry in config/deploy.yml (or set the ENV variable if that's used)"
+      end
     end
 
     def role_names