From: Anurag Priyam <anurag08priyam@...>
Date: 2011-02-23T23:46:24+09:00
Subject: Re: How to automate download pdf from web in ruby

> e.g : http://www.example.com/abc.pdf
>
> Now from above URL I just want to automate download "abc.pdf" rather
> than
>
> click on save.
>
> I am looking for some good solutions and suggestions.

On a Linux box you can happily use wget. Here is a simple use, and
throw script that I used to download video lectures (of Design of
Machine Elements :)) from NPTEL[1]. I hope this gives you an idea.

require 'rubygems'
require 'nokogiri'
require 'open-uri'

proxy = ENV["http_proxy"]
page = "http://nptel.iitm.ac.in/video.php?courseId=1063"

# get the title of all the lectures to use as a filename later
doc = Nokogiri open(page, :proxy => proxy)
titles = doc.search("td.videolink a").map(&:text)

# download url follows a common pattern
# construct the url, and download it
(1..9).each do |i|
  url =  "http://npteldownloads.iitm.ac.in/flv/1063/lec0#{i}.flv"
  lecture = titles[i - 1]
  puts lecture
  %x|wget -c '#{url}' -O '#{lecture}'|
end

(10..40).each do |i|
  url =  "http://npteldownloads.iitm.ac.in/flv/1063/lec#{i}.flv"
  lecture = titles[i - 1]
  puts lecture
  %x|wget -c '#{url}' -O '#{lecture}'|
end

[1] http://nptel.iitm.ac.in/

-- 
Anurag Priyam
http://about.me/yeban/