Class: Expurrel

Inherits:
Object
  • Object
show all
Defined in:
lib/expurrel.rb

Overview

Expurrel is a url that can be a shortened one Expurrel can decode it then.

Constant Summary collapse

PROVIDERS = 
[]
PROVIDERS_LIST_FILE = 
File.join(File.dirname(__FILE__), '..', 'urlshorteners.txt')
@@cache = 
SimpleCache.new(:max_size => 1000)

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(url) ⇒ Expurrel

Give expurrel a new url.



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# File 'lib/expurrel.rb', line 13

def initialize(url)
  @url = url
end

Class Method Details

.load_providers! ⇒ Object

Loads the list with providers into the PROVIDERS constant.



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# File 'lib/expurrel.rb', line 69

def load_providers!
  return if !PROVIDERS.empty?
  File.open(PROVIDERS_LIST_FILE, "r") .each_line do |line|
    l = line.strip
    PROVIDERS << l unless l.empty?
  end
end

.reverse_shorturl(tinyurl) ⇒ Object

Uses the header file sent back to decode the shortened url. Trick provided by: garrickvanburen.com/archive/how-to-decode-tinyurls-with-ruby



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# File 'lib/expurrel.rb', line 82

def reverse_shorturl(tinyurl)
  Net::HTTP.get_response(URI.parse(tinyurl)).to_hash['location'].to_s
end

Instance Method Details

#decode ⇒ Object

This method checks first if it’s a tiny url domain from the list.

  1. Is it a short url?

  2. It is cached? (tinyurls won’t change we can cache forever)

  3. Decode (slow!), does http request.



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# File 'lib/expurrel.rb', line 22

def decode
  return begin
    if !self.is_short_url?
      @url
    elsif @@cache.has_key?(@url)
      @@cache.value(@url)
    else
      # TODO add it to the cache
      decoded_url = self.class.reverse_shorturl(@url)
      @@cache.cache!(@url, decoded_url)
      decoded_url
    end
  end
end

#domain ⇒ Object

Get the domain



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# File 'lib/expurrel.rb', line 57

def domain
  return @domain if !@domain.nil? 
  unpacked_link = @url.scan(/(https?:\/\/|www\.)([-\w\.]+)+(:\d+)?(\/([\w\/_\.]*(\?\S+)?)?)?/)
  @domain = unpacked_link.first[1]
  return @domain
end

#is_short_domain?(domain) ⇒ Boolean

Is it a short domain?

Returns:

  • (Boolean) 


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# File 'lib/expurrel.rb', line 44

def is_short_domain?(domain)
  PROVIDERS.each do |l|
    # TODO regular expression matching
    if domain.include?(l)
      return true
    end
  end
  false
end

#is_short_url? ⇒ Boolean

Is this a short url

Returns:

  • (Boolean) 


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# File 'lib/expurrel.rb', line 38

def is_short_url?
  is_short_domain?(self.domain)
end