Webrat verify content in iframe or frameset - cucumber

Question

I am using Cucumber + Webrat + Mechanize adapter and want to test contents of pages that are iframed or framed into the selected page.
In other words:
Scenario: View header on webpage
Given I visit a page containing a frameset
When there is a header frame
Then I should see login details in frame header
The problem is of course the last step: I need to navigate to the frame header and investigate it's contents. I can verify the frame tag is here
response_body.should have_selector "frame[src][name=header]"
This leaves me with two questions:
How to read the src attribute and navigate to that page
How to navigate back to the original page

Answer 1

This would answer the first part of the question
Then /^I should see login details in frame header$/ do
within 'frame[name=header]' do |frame|
frame_src = frame.dom.attributes["src"].value
visit frame_src
response_body.should contain "Log in with digital certificate"
response_body.should_not contain "Log out"
end
end

Answer 2

you don't actually have to do it that way. Because your browser is already loading the frames automatically, you simply need to tell selenium(and thus webrat) which frame you want to look at.
When /^I select the "(.*)" frame$/ do |name|
selenium.select_frame("name=#{name}")
end

Answer 3

try this in the step definition:
within_frame("headerid") do
assert page.has_content? "login details"
end