どうにかヘッダだけ取得

やっと
modified-check.rb

require 'open-uri'

# require 'net/http'
# Net::HTTP.version_1_2 

url =ARGV[0]
uri = URI.parse(url)
# puts uri, uri.host, uri.request_uri
puts # "ok"


http=Net::HTTP.start( uri.host, 80 )
# p http.methods
# puts
req = http.head(uri.request_uri)

puts "[head]"
a={}
keys= req.each_key{}
keys.each{|a,b|
  print a,": ",b,"\n"
}
ans=""
modi=keys["last-modified"]
if modi!=nil
  ans =modi[0]
else
  ans="(no-field)"
end
puts
print "last-modified: #{ans}\n"

実行例

d:\ruby>modified-check http://hatena.g.hatena.ne.jp/files/hatena/a7c10aa65d170472.mp3

[head]
vary: Accept-Encoding
last-modified: Fri, 17 Aug 2007 09:08:08 GMT
content-type: audio/mpeg
etag: "18714a0-1867524-437e1878a4e00"
date: Tue, 28 Aug 2007 05:59:24 GMT
content-disposition: attachment; filename="070817hatenaidea.mp3"
server: Apache/2.2.4 (Unix)
content-length: 25589028
accept-ranges: bytes

last-modified: Fri, 17 Aug 2007 09:08:08 GMT

d:\ruby>