Class: Wukong::Processor::Tail

Inherits:
Filter show all
Defined in:
lib/wukong/widget/filters.rb

Overview

Skip the first n records.

Works slightly differently than the UNIX tail command which prints the last n records. This notion is less useful in a streaming context, so think of this filter as the equivalent of tail -n+.

See Also:

Constant Summary

Constants inherited from Wukong::Processor

SerializerError

Instance Attribute Summary collapse

Attributes included from Hanuman::StageInstanceMethods

#graph

Instance Method Summary collapse

Methods inherited from Filter

#process, #reject?

Methods inherited from Wukong::Processor

configure, description, #finalize, #perform_action, #process, #receive_action, #stop

Methods included from Logging

included

Methods inherited from Hanuman::Stage

#clone

Methods included from Hanuman::StageClassMethods

#builder, #label, #register, #set_builder

Methods included from Hanuman::StageInstanceMethods

#add_link, #linkable_name, #root

Instance Attribute Details

#count ⇒ Object

The current record count



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# File 'lib/wukong/widget/filters.rb', line 416

def count
  @count
end

Instance Method Details

#select?(record) ⇒ true, false

Select a record only if we've already skipped the first n records.

Parameters:

  • (Object)

Returns:

  • (true, false) 


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# File 'lib/wukong/widget/filters.rb', line 428

def select?(record)
  keep = (@count >= n)
  @count += 1
  keep
end

#setup ⇒ Object

Initializes the record count to zero.



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# File 'lib/wukong/widget/filters.rb', line 419

def setup
  self.count = 0
end