From: Alex Young <alex@...>
Date: 2006-08-17T17:24:42+09:00
Subject: Re: Newbie - Test For JPEG Image Over HTTP

Neil Charlton wrote:
> Hi
> 
> I would like to test for the existence of a .jpg image on a remote 
> server over HTTP.
> 
> I have tried 2 different methods but they are not what I need.
> 
> Method 1:
> 
> require 'open-uri'
> if open('http://example.net/path/to/image.jpg')
>    # do something
> end
> 
> Method 2:
> 
> require 'net/http'
> if Net::HTTP.get 'example.net', '/path/to/image.jpg'
>    # do something
> end
> 
> The server where the images are always returns a default page if the 
> images do not exist so the code above always returns.
> 
> What I need is a way to check what is returned is not a html page but is 
> a .jpg image.
> 

Oh.  Try this:

require 'net/http'

def url_is_a_jpg(url)
   u = URI.parse(url)
   h = Net::HTTP.new(u.host, u.port)
   r = h.head(u.path)
   return r.content_type == 'image/jpeg'
end

-- 
Alex