How do I get Nokogiri to understand my namespaces?

Question

I have the following XML document:

  @NOT_USED@         


        

Answer 1

I see a two different options for you:

1. Remove all the namespaces

   http://www.rubydoc.info/github/sparklemotion/nokogiri/Nokogiri/XML/Document#remove_namespaces%21-instance_method

   Brute force way of doing it. Could lead to problems where there are namespace collisions.

2. Use collect_namespaces

   http://www.rubydoc.info/github/sparklemotion/nokogiri/Nokogiri/XML/Document#collect_namespaces-instance_method

   A much better solution. You could use this once to identify the namespaces (say in irb) and hard-code them.

   OR

   Use it at runtime, and supply it as the second argument to https://www.rubydoc.info/github/sparklemotion/nokogiri/Nokogiri/XML/Searchable#xpath-instance_method

Answer 2

It doesn't look like the namespaces in this document are correctly declared - there should be xmlns:samlp and xmlns:saml attributes on the root node. In cases like this, Nokogiri essentially ignores the namespaces (as it can't map them to URIs or URNs), so your XPath works if you remove them, i.e.

doc.xpath(XPATH_QUERY)