[BUG] respond_to problems with safari (and maybe other browsers)

You need to be more careful in the order you specify formats in your respond_to block. In the first example xml is above html, in the second it's the opposite. The actual response type chosen is based on the order you specify these formats together with the order the formats are listed in the accepts header sent by each browser, firefox and safari presumably sending different lists, hence the 'bug'.

And what about using the params[:format]?

Hey, I'm passing the format, why not use it?

I'm expliciting telling rails to render using the requested format (passed in url), and want it that way!

@mime_type_priority = Array(Mime::Type.lookup_by_extension(@request.parameters[:format]) @request.accepts)

It works like you say

class RespondToController < ActionController::Base
  def html_xml_or_rss
    respond_to do |type|
      type.html { render :text => "HTML"    }
      type.xml  { render :text => "XML"     }
      type.rss  { render :text => "RSS"     }
      type.all  { render :text => "Nothing" }
    end
    #...
  end
end


class MimeControllerTest < Test::Unit::TestCase
  def test_forced_format
    get :html_xml_or_rss
    assert_equal "HTML", @response.body

    get :html_xml_or_rss, :format => "html"
    assert_equal "HTML", @response.body

    get :html_xml_or_rss, :format => "xml"
    assert_equal "XML", @response.body

    get :html_xml_or_rss, :format => "rss"
    assert_equal "RSS", @response.body
  end
end

Consither attaching a failing test case if you are willing to reopen the ticket.

Ok, before reopen the ticket let explain it better.

For explanation:

Safari sends the header HTTP ACCEPT = "/". This way it will accept anything the server gives it. Which on the surface seems just fine, but rails does not work that way. If the request (from the browser) does not specify a mime type in the url, then rails tries to figure out what the browser wants based on the accepts header. In this case the browser will take anything, so rails gave it the first thing on the list.

I don't think it's completely a Rails bug. And it's not a Safari bug too. But, I think the implicit format needs to be html. And, show the other formats when requesting it. Actually, it's that way when we aren't using respond_to, right? It loads the erb (html) file.

At least I think this should be on documentation, since took so many times to figure out that.

Ok, enough talking, let's code.

class RespondToController < ActionController::Base
  def html_xml_or_rss
    respond_to do |type|
      type.xml  { render :text => "XML"     }
      type.html { render :text => "HTML"    }
      type.rss  { render :text => "RSS"     }
      type.all  { render :text => "Nothing" }
    end
    #...
  end
end


class MimeControllerTest < Test::Unit::TestCase
  def test_forced_format
    get :html_xml_or_rss
    assert_equal "HTML", @response.body

    get :html_xml_or_rss, :format => "html"
    assert_equal "HTML", @response.body

    get :html_xml_or_rss, :format => "xml"
    assert_equal "XML", @response.body

    get :html_xml_or_rss, :format => "rss"
    assert_equal "RSS", @response.body
  end
end

This test pass (using ruby), but while on Safari, it's not what happens. I got: "XML" as response.body!

Reopening this for better attention.