Q:

ruby nokogiri not reading my xml file

I have an metadata.xml file that has :    
<MediaItem ActualEndTime="8/2/2017 5:05:01 PM" ActualStartTime="8/2/2017 4:00:01 PM" Clip="False" ClipEndTime="1/1/0001 12:00:00 AM" ClipParentId="00000000-0000-0000-0000-000000000000" ClipStartTime="1/1/0001 12:00:00 AM" CreatedDate="1/1/0001 12:00:00 AM" DateAdded="1/1/0001 12:00:00 AM" Duration="01:04:59.8290000" FileFormat="0" FileSize="0" Genre="Interview" GuideEndTime="8/2/2017 5:00:00 PM" GuideStartTime="8/2/2017 4:00:00 PM" MovieId="00000000-0000-0000-0000-000000000000" MovieYear="0" NumParts="0" OriginalAirDate="8/2/2017 12:00:00 AM" OriginalFileSize="3636725627" PartNum="0" RecordingType="Episodic" ShowSqueeze="True" TargetEndTime="8/2/2017 5:05:00 PM" TargetStartTime="8/2/2017 4:00:00 PM" UserId="" VideoHeight="0" VideoWidth="0" />   

How do I parse it with ruby and nokogiri?
I've tried :     
f = File.open path
puts "f  : #{f}"
metadata  = {}
doc = Nokogiri::XML(f)
puts "doc : #{doc}"
p = doc.xpath("//ActualStartTime")
puts "p : #{p}"
puts "++++++++++++++++++++++++++++++++++++++"

but I get this output :    
f  : #<File:0x00000002755c40>
doc : <?xml version="1.0"?>
p : 
+++++++++++++++++++++++++++++++++++++++++++   

What I am missing? I want to get ActualStartTime value, Duration value and Genre value.
update 
metadata  = {}
f = File.read(path)
puts "f  : #{f}"
doc = Nokogiri::XML(f)
p = doc.xpath("//@ActualStartTime")
puts "p : #{p}"
metadata['Duration'] = doc.xpath("//MediaItem/@Duration")
puts "metadata['Duration']  : #{metadata['Duration']}"    

output:   
f : <MediaItem ActualEndTime="8/2/2017 5:05:01 PM" ActualStartTime="8/2/2017 4:00:01 PM" Clip="False" ClipEndTime="1/1/0001 12:00:00 AM" ClipParentId="00000000-0000-0000-0000-000000000000" ClipStartTime="1/1/0001 12:00:00 AM" CreatedDate="1/1/0001 12:00:00 AM" DateAdded="1/1/0001 12:00:00 AM" Duration="01:04:59.8290000" FileFormat="0" FileSize="0" Genre="Interview" GuideEndTime="8/2/2017 5:00:00 PM" GuideStartTime="8/2/2017 4:00:00 PM" MovieId="00000000-0000-0000-0000-000000000000" MovieYear="0" NumParts="0" OriginalAirDate="8/2/2017 12:00:00 AM" OriginalFileSize="3636725627" PartNum="0" RecordingType="Episodic" ShowSqueeze="True" TargetEndTime="8/2/2017 5:05:00 PM" TargetStartTime="8/2/2017 4:00:00 PM" UserId="" VideoHeight="0" VideoWidth="0" />   
p : 
metadata['Duration']  : 

A:

You're opening the file, but you're never actually reading the file contents (and also not closing the file after). You can read the file through
begin
  file = File.open './metadata.xml'
  f = file.read
ensure
  file.close
end

or through one of the shortcuts:
# closes file after block finishes
f = File.open('./metadata.xml') { |f| f.read }

or, since reading is such a common thing, you can use File.read
f = File.read('./metadata.xml')

and now Nokogiri will read f just fine, though you'll need to use
p = doc.xpath("//@ActualStartTime")

since it's an attribute.

