How can I extract URLs from HTML content with a Ruby regexp? - ruby

Question

This is an example since it is not easy to explain:
<li id="l_f6a1ok3n4d4p" class="online"> <div class="link"> random strings - 4 <a style="float:left; display:block; padding-top:3px;" href="http://www.webtrackerplus.com/?page=flowplayerregister&a_aid=&a_bid=&chan=flow"><img border="0" src="/resources/img/fdf.gif"></a> <!-- a class="none" href="#">random strings - 4 site2.com - # - </a --> </div> <div class="params"> <span>Submited: </span>7 June 2015 | <span>Host: </span>site2.com </div> <div class="report"> <a title="" href="javascript:report(3191274,%203,%202164691,%201)" class="alert"></a> <a title="" href="javascript:report(3191274,%203,%202164691,%200)" class="work"></a> <b>100% said work</b> </div> <div class="clear"></div> </li> <li id="l_zsgn82c4b96d" class="online"> <div class="link"> <a href="javascript:show('zsgn82c4b96d','random%20strings%204',%20'site1.com');%20" onclick="visited('zsgn82c4b96d');" style
In the above content I want to extract from
javascript:show('f6a1ok3n4d4p','random%20strings%204',%20'site2.com')
the string "f6a1ok3n4d4p" and "site2.com" then make it as
http://site2.com/f6a1ok3n4d4p
and same for
javascript:show('zsgn82c4b96d','random%20strings%204',%20'site1.com')
to become
http://site1.com/zsgn82c4b96d
I need it to be done with Ruby regex.

Answer 1

You can proceed like this:
require 'uri'
str = "javascript:show('f6a1ok3n4d4p','random%20strings%204',%20'site2.com')"
# regex scan to get values within javascript:show
vals = str.scan(/javascript:show\((.*)\)/)[0][0].split(',')
# => ["'f6a1ok3n4d4p'", "'random%20strings%204'", "%20'site2.com'"]
# joining resultant Array elements to generate url
url = "http://" + URI.decode(a.last).tr("'", '').strip + "/" + a.first.tr("'", '')
# => "http://site2.com/f6a1ok3n4d4p"
obviously my answer is not foolproof. You can make it better with checks for what if scan returns []?

Answer 2

This should do the trick, though the regexp isn't particularly flexible.
js_link_regex = /href=\"javascript:show\('([^']+)','[^']+',%20'([^']+)'\)/
link = <<eos
<li id="l_f6a1ok3n4d4p" class="online"> <div class="link"> random strings - 4 <a style="float:left; display:block; padding-top:3px;" href="http://www.webtrackerplus.com/?page=flowplayerregister&a_aid=&a_bid=&chan=flow"><img border="0" src="/resources/img/fdf.gif"></a> <!-- a class="none" href="#">random strings - 4 site2.com - # - </a --> </div> <div class="params"> <span>Submited: </span>7 June 2015 | <span>Host: </span>site2.com </div> <div class="report"> <a title="" href="javascript:report(3191274,%203,%202164691,%201)" class="alert"></a> <a title="" href="javascript:report(3191274,%203,%202164691,%200)" class="work"></a> <b>100% said work</b> </div> <div class="clear"></div> </li> <li id="l_zsgn82c4b96d" class="online"> <div class="link"> <a href="javascript:show('zsgn82c4b96d','random%20strings%204',%20'site1.com');%20" onclick="visited('zsgn82c4b96d');" style
eos
matches = link.scan(js_link_regex)
matches.each do |match|
puts "http://#{match[1]}/#{match[0]}"
end

Answer 3

To just match your case,
str = "javascript:show('f6a1ok3n4d4p','random%20strings%204',%20'site2.com')"
parts = str.scan(/'([\w|\.]+)'/).flatten # => ["f6a1ok3n4d4p", "site2.com"]
puts "http://#{parts[1]}/#{parts[0]}" # => http://site2.com/f6a1ok3n4d4p