Class: Guillotine::Adapters::RiakAdapter

Inherits:
Adapter
  • Object
show all
Defined in:
lib/guillotine/adapters/riak_adapter.rb

Overview

Stores shortened URLs in Riak. Totally scales.

Constant Summary collapse

PLAIN = 
'text/plain'.freeze

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods inherited from Adapter

#parse_url, #shorten

Constructor Details

#initialize(code_bucket, url_bucket = nil) ⇒ RiakAdapter

Initializes the adapter.

code_bucket - The Riak::Bucket for all code keys. url_bucket - The Riak::Bucket for all url keys. If this is not

given, the code bucket is used for all keys.



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# File 'lib/guillotine/adapters/riak_adapter.rb', line 15

def initialize(code_bucket, url_bucket = nil)
  @code_bucket = code_bucket
  @url_bucket  = url_bucket || @code_bucket
end

Instance Attribute Details

#code_bucket ⇒ Object (readonly)

Returns the value of attribute code_bucket.



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# File 'lib/guillotine/adapters/riak_adapter.rb', line 8

def code_bucket
  @code_bucket
end

#url_bucket ⇒ Object (readonly)

Returns the value of attribute url_bucket.



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# File 'lib/guillotine/adapters/riak_adapter.rb', line 8

def url_bucket
  @url_bucket
end

Instance Method Details

#add(url, code = nil) ⇒ Object

Public: Stores the shortened version of a URL.

url - The String URL to shorten and store. code - Optional String code for the URL.

Returns the unique String code for the URL. If the URL is added multiple times, this should return the same code.



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# File 'lib/guillotine/adapters/riak_adapter.rb', line 27

def add(url, code = nil)
  sha     = url_key url
  url_obj = @url_bucket.get_or_new sha, :r => 1
  if url_obj.raw_data
    fix_url_object(url_obj)
    code = url_obj.data
  end

  code   ||= shorten url
  code_obj = @code_bucket.get_or_new code
  code_obj.content_type = url_obj.content_type = PLAIN

  if existing_url = code_obj.data # key exists
    raise DuplicateCodeError.new(existing_url, url, code) if url_key(existing_url) != sha
  end

  if !url_obj.data # unsaved
    url_obj.data = code
    url_obj.store
  end

  code_obj.data = url
  code_obj.store
  code
end

#clear(url) ⇒ Object

Public: Removes the assigned short code for a URL.

url - The String URL to remove.

Returns nothing.



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# File 'lib/guillotine/adapters/riak_adapter.rb', line 80

def clear(url)
  if code_obj = code_object(url)
    @url_bucket.delete  code_obj.key
    @code_bucket.delete code_obj.data
  end
end

#code_for(url) ⇒ Object

Public: Retrieves the code for a given URL.

url - The String URL to lookup.

Returns the String code, or nil if none is found.



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# File 'lib/guillotine/adapters/riak_adapter.rb', line 69

def code_for(url)
  if obj = code_object(url)
    obj.data
  end
end

#code_object(url) ⇒ Object

Retrieves the code riak value for a given URL.

url - The String URL to lookup.

Returns a Riak::RObject, or nil if none is found.



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# File 'lib/guillotine/adapters/riak_adapter.rb', line 103

def code_object(url)
  sha = url_key url
  if o = @url_bucket.get(sha, :r => 1)
    fix_url_object(o)
  end
rescue Riak::FailedRequest => err
  raise unless err.not_found?
end

#find(code) ⇒ Object

Public: Retrieves a URL from the code.

code - The String code to lookup the URL.

Returns the String URL.



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# File 'lib/guillotine/adapters/riak_adapter.rb', line 58

def find(code)
  if obj = url_object(code)
    obj.data
  end
end

#fix_url_object(obj, data = nil) ⇒ Object

Fixes a bug in Guillotine 1.0.2 where the content type on url objects was not being set. The ruby Riak::Client defaults to JSON, so strings were being saved as “somecode”, which is unparseable by JSON.



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# File 'lib/guillotine/adapters/riak_adapter.rb', line 115

def fix_url_object(obj, data = nil)
  if data
    obj.content_type = PLAIN
    obj.data = data
    obj.store
    return obj
  end
  case obj.content_type
    when /json/ then fix_url_object(obj, JSON.parse(%({"data":#{obj.raw_data}}))['data'])
    when PLAIN  then obj
    else fix_url_object(obj, obj.data) # old values had the right data but the content type was application/x-www-form-urlencoded
  end
end

#url_key(url) ⇒ Object 



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# File 'lib/guillotine/adapters/riak_adapter.rb', line 129

def url_key(url)
  Digest::SHA1.hexdigest url.downcase
end

#url_object(code) ⇒ Object

Retrieves a URL riak value from the code.

code - The String code to lookup the URL.

Returns a Riak::RObject, or nil if none is found.



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# File 'lib/guillotine/adapters/riak_adapter.rb', line 92

def url_object(code)
  @code_bucket.get(code, :r => 1)
rescue Riak::FailedRequest => err
  raise unless err.not_found?
end