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How to merge / merge xml files into one file and return it?

I am using the Last.fm API and I am trying to get a lot of information about a specific user and return it to xml. So here is the challenge in my opinion:

<%= form_tag fetch_user_path, :remote => true, :'data-type' => 'xml', :id => 'search' do %>
  <%= text_field_tag :q %>
<% end %>

So, as you can see, it expects XML, and I correctly handle the callback using jQuery. Then in my controller:

# fetch_controller.rb
def user
  username = params[:q].gsub(' ','+')
  get_info_url = "http://ws.audioscrobbler.com/2.0/?method=user.getinfo&user=#{username}&api_key=#{API_KEY}"
  get_friends_url = "http://ws.audioscrobbler.com/2.0/?method=user.getfriends&user=#{username}&api_key=#{API_KEY}"

  respond_to do |format|
    format.xml {
      begin
        @info = Nokogiri::XML(open(get_info_url))
        @friends = Nokogiri::XML(open(get_friends_url))
      rescue Exception => e
        if e.message == '400 Bad Request'
          render xml: { :error => 'User not found.' }, :status => 400
        else
          render xml: { :error => 'Connection to Last.fm failed.' }, :status => 500
        end
      else
        # Here, I want to render @info + @friends!
        render xml: @info
      end
    }
end

Thus, I am correctly returning the xml returned get_info_url. However, I want to join this xml for the xml returned get_friends_url. How can i do this?

After Ben Miller's answer, I get a parserror on my callback. I think this is due to both xml files containing xml version. And maybe the combined file is not working? I see that xml files are concatenated, this is how they look with console.log:

Error: Invalid XML: <?xml version="1.0"?>
<Combined>
  <UserInfo>
    <?xml version="1.0" encoding="utf-8"??>
    <lfm status="ok">
      <user>
        # lots of info about the user
      </user>
    </lfm>
  </UserInfo>
  <FriendInfo>
    <?xml version="1.0" encoding="utf-8"??>
      <lfm status="ok">
        <friends for="user" page="1" perpage="50" totalpages="2" total="96">
          # lots of info about the user friends
        </friends>
      </lfm>
  </FriendInfo>
</Combined>
+3
1

: XML , node.

Nokogiri builder

def user
  username = params[:q].gsub(' ','+')
  get_info_url = "http://ws.audioscrobbler.com/2.0/?method=user.getinfo&user=#{username}&api_key=#{API_KEY}"
  get_friends_url = "http://ws.audioscrobbler.com/2.0/?method=user.getfriends&user=#{username}&api_key=#{API_KEY}"

  respond_to do |format|
    format.xml {
      begin
        info_xml = Nokogiri::XML(open(get_info_url))
        friends_xml = Nokogiri::XML(open(get_friends_url))
        builder = Nokogiri::XML::Builder.new do |xml_out|
          xml_out.Combined {
            xml_out.UserInfo {
              node = info_xml.at_xpath("//user")
              xml_out << node.to_xml.to_str
            }
            xml_out.FriendInfo {
              node = friends_xml.at_xpath("//friends")
              xml_out << node.to_xml.to_str
            }
          }
        end
      rescue Exception => e
        if e.message == '400 Bad Request'
          render xml: { :error => 'User not found.' }, :status => 400
        else
          render xml: { :error => 'Connection to Last.fm failed.' }, :status => 500
        end
      else
        render xml: builder.to_xml
      end
    }
  end
end
+3

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