Ruby: strip iframe and convert its src to a var - ruby-on-rails

Question

I'm trying to parse a string that has an iframe in it, convert its src attribute to a specially-formatted Ruby variable, then replace the iframe in the string with the Ruby variable formatted in a particular way. So far I've written this:
def video_parse(string)
if string.include?('youtube.com/?v=')
url = 'youtube.com/?v='
string.gsub!('<iframe>.*</iframe>', video_service('YOUTUBE', vid(string, url)))
end
if string.include?('player.vimeo.com/video/')
url = 'player.vimeo.com/video/'
string.gsub!('<iframe>.*</iframe>', video_service('VIMEO', vid(string, url)))
end
string
end
def vid(string, url)
string.split(url).last.split(/['"]/).first
end
def video_service(service, vid)
"*|#{service}:[$vid=#{vid}]|*"
end
But it doesn't replace anything. I suspect my wildcard iframe tag selection is wrong, plus my vid method is a little clunky. How can I get my wildcard in gsub to work correctly? And for bonus points, can I write it a little more efficiently so I'm not parsing string to reformat the src in iframe?
Update
String looks something like this:
string = 'resources rather than creating our luck through innovation.\n<br>\n<br> \n<iframe allowfullscreen=\"\" frameborder=\"0\" height=\"311\" mozallowfullscreen=\"\" name=\"vimeo\" src=\"http://player.vimeo.com/video/222234444\" webkitallowfullscreen=\"\" width=\"550\"></iframe>\n<br>\n<br>\nThat hasn’t stoppe'
Second attempt looks like this, still doesn't replace anything:
def mailchimp_video_parse(string)
if string.include?('youtube.com/?v=')
string.gsub!(iframe) { video_service('YOUTUBE', vid(Regexp.last_match[1])) }
end
if string.include?('player.vimeo.com/video/')
string.gsub!(iframe) { video_service('VIMEO', vid(Regexp.last_match[1])) }
end
string
end
def vid(iframe)
iframe.split!('src').last.split!(/"/).first
end
def iframe
'<iframe.*<\/iframe>'
end
def video_service(service, vid)
"*|#{service}:[$vid=#{vid}]|*"
end
Still nothing.

Answer 1

A bit safer with Nokogiri:
d = Nokogiri::HTML(string)
d.css('iframe').each do |i|
if i['src'] =~ %r{(youtube|vimeo).*?([^/]+)$}i
i.replace(video_service($1.upcase, $2)
end
end
puts d.to_html
(But note that it is less efficient than the pure regexp solution, as Nokogiri will parse the whole HTML.)

Answer 2

The iframe method should be /<iframe.*<\/iframe>/ for it to be properly be recognized as a regex
The Regexp.last_match[1] should be Regexp.last_match[0] in the mailchimp_video_parse method
split! needs to be just split in the vid method (there is no split! method in Ruby)
Edited methods:
def mailchimp_video_parse(string)
if string.include?('youtube.com/?v=')
string.gsub!(iframe) { video_service('YOUTUBE', vid(Regexp.last_match[0])) }
end
if string.include?('player.vimeo.com/video/')
string.gsub!(iframe) { video_service('VIMEO', vid(Regexp.last_match[0])) }
end
string
end
def vid(iframe)
iframe.split('src').last.split(/"/).first
end
def iframe
/<iframe.*<\/iframe>/
end