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Showing 11 - 20 of 136 total

On This Page:

  1. 1 HTML stripper
  2. 2 Ubuntu 7.10: bootstrap a Ruby on Rails stack
  3. 3 Scrape torrents on btjunkie
  4. 4 Scrape MySpace friend thumbnails
  5. 5 Scrape YouTube thumbnails
  1. 6 jQuery and Rails' respond_to
  2. 7 writing destructive string methods in Ruby
  3. 8 simple Ruby RSS reader
  4. 9 acts_as_state_machine model
  5. 10 Enumerable vs. Enumerator. Standard Library vs. Core Library in Ruby.

HTML stripper

to ruby html strip by minofare on Jan 15, 2008 2 Comments
// description of your code here

str = <<HTML_TEXT
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
   "http://www.w3.org/TR/html4/loose.dtd">
<html>
<body>
  <h1>Application error</h1>
  <p>Change this error message for exceptions thrown outside of an action (like 
in Dispatcher setups or broken Ruby code) in public/500.html</p>
</body>
</html>
HTML_TEXT

puts str.gsub(/<\/?[^>]*>/, "")

Ubuntu 7.10: bootstrap a Ruby on Rails stack

to ruby rails sysadmin config rubyonrails ubuntu linux app stack install by jamiew on Jan 15, 2008
// get started with ubuntu 7.1
// e.g. on a new slice from http://slicehost.com !

# 1) make yrself a user and stop being root

# 2) main web stack + ruby
sudo aptitude install -y make screen
sudo aptitude install -y apache2 php5 mysql-server
sudo aptitude install -y subversion postfix
sudo aptitude install -y ruby1.8 ruby1.8-dev rubygems irb
sudo aptitude install -y imagemagick librmagick-ruby1.8 librmagick-ruby-doc libfreetype6-dev xml-core

# 3) gemz
# rubygems appears to be broken as hell. 
# gem update --system does squat
# had to manually d/l rubygems 1.0.1, ruby setup.rb
wget http://rubyforge.org/frs/download.php/29548/rubygems-1.0.1.tgz
tar xzvf rubygems-1.0.1.tgz
cd rubygems-1.0.1
sudo ruby setup.rb
sudo gem install rails mongrel merb map_by_method

Scrape torrents on btjunkie

to ruby www file mechanize scraping save scrape btjunkie torrents bittorrent by jamiew on Jan 12, 2008
// download all .torrent links on the btjunkie frontpage
//
// more fun with mechanize @
// http://tramchase.com/scrape-myspace-youtube-torrents-for-fun-and-profit

agent = WWW::Mechanize.new
agent.get("http://btjunkie.org/")
links = agent.page.search('.tor_details tr a')
hrefs = links.map { |m| m['href'] }.select { |u| u =~ /\.torrent$/ } # just links ending in .torrent
FileUtils.mkdir_p('btjunkie-torrents') # keep it neat
hrefs.each { |torrent|
  filename = "btjunkie-torrents/#{torrent[0].split('/')[-2]}"
  puts "Saving #{torrent} as #{filename}"
  agent.get(torrent).save_as(filename)
}

Scrape MySpace friend thumbnails

to ruby www file mechanize scraping save scrape myspace by jamiew on Jan 12, 2008
// fetch all img's from a myspace profile's .friendSpace div
// more @ http://tramchase.com/scrape-myspace-youtube-torrents-for-fun-and-profit

agent = WWW::Mechanize.new
agent.get("http://myspace.com/graffitiresearchlab")
links = agent.page.search('.friendSpace img') # found w/ firebug
FileUtils.mkdir_p 'myspace-images' # make the images dir
links.each_with_index { |link, index| 
  url = link['src']
  puts "Saving thumbnail #{url}"
  agent.get(url).save_as("myspace-images/top_friend#{index}_#{File.basename url}")
}

Scrape YouTube thumbnails

to ruby www file video mechanize scraping youtube save scrape by jamiew on Jan 12, 2008
// fun with mechanize
// more @ http://tramchase.com/scrape-myspace-youtube-torrents-for-fun-and-profit

agent = WWW::Mechanize.new
url = "http://gdata.youtube.com/feeds/api/standardfeeds/most_viewed" # all time
page = agent.get(url)
# parse again w/ Hpcricot for some XML convenience
doc = Hpricot.parse(page.body)
# pp (doc/:entry) # like "search"; cool division overload
images = (doc/'media:thumbnail') # use strings instead of symbols for namespaces
FileUtils.mkdir_p 'youtube-images' # make the images dir
urls = images.map { |i| i[:url] }
urls.each_with_index do |file,index|
  puts "Saving image #{file}"
  agent.get(file).save_as("youtube-images/vid#{index}_#{File.basename file}")
end

jQuery and Rails' respond_to

to ruby rails javascript rubyonrails ajax js jquery respond_to by jamiew on Jan 12, 2008
// Just throw this at the bottom of your application.js and you’re good to go: all jQuery ajax requests will trigger the wants.js block of your respond_to declaration, exactly like you’d expect. Enjoy.
// via: http://ozmm.org/posts/jquery_and_respond_to.html

jQuery.ajaxSetup({ ‘beforeSend’: function(xhr) {xhr.setRequestHeader(“Accept”, “text/javascript”)} })

writing destructive string methods in Ruby

to ruby rails by deckard on Jan 10, 2008
Use string class' method "replace" to overwrite its "self" value.

Example:

  def decapitalize!
    replace (self.reverse.chop + self.reverse.last.downcase).reverse
  end
  
  def decapitalize
    dup.decapitalize!
  end

simple Ruby RSS reader

to ruby rss xml scraping feed by jamiew on Jan 09, 2008
// fetch & parse RSS into an object

require 'rss/2.0'
require 'open-uri'

class RssReader

  def parseFeed (url, length)
    feed_url = url
    output = "";
    open(feed_url) do |http|
      response = http.read
      result = RSS::Parser.parse(response, false)
      output = "<span class=\"feedTitle\">#{result.channel.title}</span><br /><ul>" 
      result.items.each_with_index do |item, i|
        output += "<li><a href=\"#{item.link}\">#{item.title}</a></li>" if ++i < length  
      end 
      output += "</ul>" 
    end
    return output
  end

end

acts_as_state_machine model

to ruby rails activerecord state acts_as_state_machine by jamiew on Jan 09, 2008
// ActiveRecord plugin for managing state changes
// elitists.textdriven.com/svn/plugins/acts_as_state_machine/ 

class Something < ActiveRecord::Base

  # Validations
  validate :validate_state_change

  # State Machine States
  acts_as_state_machine :initial => :new
  state :new
  state :enabled,   :after => :after_enabled
  state :disabled,  :after => :after_disabled

  # State Machine Events
  event :enabled do
    transitions :from => :new,      :to => :enabled
    transitions :from => :disabled, :to => :enabled
  end
  
  event :disabled do
    transitions :from => :new,      :to => :disabled
    transitions :from => :enabled,  :to => :disabled
  end

  # Instance Methods
  def validate_state_change
    return if new_record?
    old = self.class.find(id)
    old_state = old.state
    new_state = self.state
    self.state = old_state
    if old_state != new_state
      begin
        if self.method("#{new_state}!").call != true
          errors.add(:state, "cannot transition from #{old_state} to #{new_state}")
        end
      rescue NameError
      end
      self.state = new_state
    end
  end
end

Enumerable vs. Enumerator. Standard Library vs. Core Library in Ruby.

to ruby by deckard on Nov 25, 2007
Rdoc is causing some serious confusion with libraries.

In core documentation, Enumerable defines each_slice method.

Extend this module into your class and each_slice is not defined.

Reason? each_slice is NOT in the core Enumerable module, but rather the Standard Library Enumerable::Enumerator class, even though the ruby-doc core class documents say otherwise.

You must 

require 'enumerator'


to have each_slice is available as a method to your classes.
Showing 11 - 20 of 136 total

On This Page:

  1. 1 HTML stripper
  2. 2 Ubuntu 7.10: bootstrap a Ruby on Rails stack
  3. 3 Scrape torrents on btjunkie
  4. 4 Scrape MySpace friend thumbnails
  5. 5 Scrape YouTube thumbnails
  1. 6 jQuery and Rails' respond_to
  2. 7 writing destructive string methods in Ruby
  3. 8 simple Ruby RSS reader
  4. 9 acts_as_state_machine model
  5. 10 Enumerable vs. Enumerator. Standard Library vs. Core Library in Ruby.