attribute content_type
Ruby on Rails 4.2.11.3
Since v3.0.20 Last seen in v4.2.11.3Sets the HTTP response’s content MIME type. For example, in the controller you could write this:
response.content_type = "text/plain"
If a character set has been defined for this response (see charset=) then the character set information will also be included in the content type information.