Foreach loop in XML generator not breaking - ruby

Question

I am trying to generate XML, but the loop isn't breaking. Here is a part of the code:
#key = 0
#cont.each do |pr|
xml.product {
#key += 1
puts #key.to_s
begin
#main = Nokogiri::HTML(open(#url+pr['href'], "User-Agent" => "Ruby/#{RUBY_VERSION}","From" => "foo#bar.invalid", "Referer" => "http://www.ruby-lang.org/"))
rescue
puts "rescue"
next
end
puts pr['href']
puts #key.to_s
break //this break doesn't work
#something else
}
end
Most interesting is that in the final generated XML file, break worked. The file contains only one product, but on the console #key was printed fully, which means the foreach loop doesn't break.
Could it be a Nokogiri XML-specific error, because of open brackets in the head of the loop?

Answer 1

In general I think how you're going about trying to generate the XML is confused. Don't convolute your code any more than necessary; Instead of starting to generate some XML then aborting it inside the block because you can't find the page you want, grab the pages you want first, then start processing.
I'd move the begin/rescue block outside the XML generation. Its existence inside the XML generation block results in poor logic and questionable practices of using next and break. Instead I'd recommend something like this untested code:
#main = []
#cont.each do |pr|
begin
#main << Nokogiri::HTML(
open(#url + pr['href'])
)
rescue
puts 'rescue'
next
end
end
builder = Nokogiri::XML::Builder.new do |xml|
xml.root {
xml.products {
#main.each do |m|
xml.product {
xml.id_ m.at('id').text
xml.name m.at('name').text
}
end
}
}
end
puts builder.to_xml
Which makes it easy to see that the code is keying off being able to retrieve a page.
This code is untested because we have no idea what your input values are or what your output should look like. Having valid input, expected output and a working example of your code that demonstrates the problem is essential if you want help debugging a problem with your code.
The use of #url + pr['href'] isn't generally a good idea. Instead use the URI class to build up the URL for you. URI handles encoding and ensures the URI is valid.