Class: UniqueContentSet

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

Overview

Stores a set of unique content. This is used to check if new content being added has been seen already.

Constant Summary collapse

VERSION = 
'0.1.0'

Class Attribute Summary collapse

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(*args) ⇒ UniqueContentSet

Returns a new instance of UniqueContentSet.



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# File 'lib/unique_content_set.rb', line 20

def initialize(*args)
  @redis = self.class.redis

  # Turn the given args into a redis key, with pieces separated by ':'.
  args.unshift self.class.redis_prefix
  args.compact!
  args.map! { |a| a.to_s }
  @key = args * ":"
end

Class Attribute Details

.redis ⇒ Object

Sets are stored in Redis.



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# File 'lib/unique_content_set.rb', line 10

def redis
  @redis
end

.redis_prefix ⇒ Object

Sets are stored in Redis.



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# File 'lib/unique_content_set.rb', line 10

def redis_prefix
  @redis_prefix
end

Instance Attribute Details

#key ⇒ Object (readonly)

Returns the value of attribute key.



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# File 'lib/unique_content_set.rb', line 18

def key
  @key
end

Instance Method Details

#add(content, time = Time.now) ⇒ Object

Public: Adds the given content to the current set, scored by the given time.

content - String content to add to the set. time - The current Time the content was created.

Returns true if this is the first occurence of the content, or false.



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# File 'lib/unique_content_set.rb', line 37

def add(content, time = Time.now)
  @redis.zadd(@key, time.to_i, member_from(content))
end

#delete_before(time) ⇒ Object

Public: Removes content posted before the given time.

time - The latest Time that should be purged from the set.

Returns a Fixnum of the number of removed entries.



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# File 'lib/unique_content_set.rb', line 55

def delete_before(time)
  @redis.zremrangebyscore(@key, 0, time.to_i+1)
end

#exist?(content) ⇒ Boolean

Public: Looks for the given content in the current set.

content - String content that is being checked.

Returns true if the content is a member of the set, or false.

Returns:

  • (Boolean) 


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# File 'lib/unique_content_set.rb', line 46

def exist?(content)
  !!@redis.zscore(@key, member_from(content))
end