Class: Jrf::Pipeline

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

Instance Method Summary collapse

Constructor Details

#initialize(*blocks) ⇒ Pipeline

Returns a new instance of Pipeline.

Raises:

  • (ArgumentError) 


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# File 'lib/jrf/pipeline.rb', line 9

def initialize(*blocks)
  raise ArgumentError, "at least one stage block is required" if blocks.empty?

  @ctx = RowContext.new
  @stages = blocks.map { |block| Stage.new(@ctx, block, src: nil) }
end

Instance Method Details

#call(input) {|value| ... } ⇒ Array?

Run the pipeline on an enumerable of input values.

Without a block, returns an Array of output values. With a block, streams each output value to the block.

Parameters:

  • input (Enumerable) —

    input values to process

Yield Parameters:

  • value —

    output value

Returns:

  • (Array, nil) —

    output values (without block), or nil (with block)



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# File 'lib/jrf/pipeline.rb', line 24

def call(input, &on_output)
  if on_output.nil?
    results = []
    on_output = proc { |value| results << value }
  end

  begin
    input.each { |value| process_value(value, @stages, &on_output) }
  ensure
    flush_reducers(@stages, &on_output)
  end

  results unless results.nil?
end