Module: Itiel::Transform::ChainedStep

Included in:
CalculatedColumns, ConstantColumn, MapValues, RemoveColumn, RenameColumn, SelectColumn
Defined in:
lib/itiel/transform/chained_step.rb

Overview

Defined the behavior of the Transformation and how they handle the data stream.

All classes including this module should implement a transform! method that does the real transformation.

Than method will be called as soon as the transformation receives input.

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#next_step ⇒ Object

Returns the value of attribute next_step.



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# File 'lib/itiel/transform/chained_step.rb', line 14

def next_step
  @next_step
end

Instance Method Details

#input=(stream) ⇒ Object 



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# File 'lib/itiel/transform/chained_step.rb', line 18

def input=(stream)
  next_step.input = transform!(stream)
end

#transform!(stream) ⇒ Object 



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# File 'lib/itiel/transform/chained_step.rb', line 22

def transform!(stream)
  raise Itiel::MethodNotImplementedException.new "You need to define the transform! method in the implementing class"
end