Encode capistrano output messages to UTF-8 before manipulating them.

lib/capistrano/datadog.rb

@@ -92,7 +92,7 @@ def report()
           message_content = (@logging_output[name] || []).join('')
           message = if !message_content.empty? then
             # Strip out color control characters
-            message_content = message_content.gsub(/\e\[(\d+)m/, '')
+            message_content = sanitize_encoding(message_content).gsub(/\e\[(\d+)m/, '')
             "@@@\n#{message_content}@@@" else "" end
 
           Dogapi::Event.new(message,
@@ -105,6 +105,11 @@ def report()
           )
         end
       end
+
+      def sanitize_encoding(string)
+        return string unless defined?(::Encoding) && string.encoding == Encoding::BINARY
+        string.encode(Encoding::UTF_8, Encoding::BINARY, invalid: :replace, undef: :replace, replace: '')
+      end
     end
 
   end