Class: SimpleIterator::File

Inherits:
Plain
  • Object
show all
Defined in:
lib/simple_iterator/file.rb

Instance Method Summary collapse

Methods inherited from Plain

#index, #next

Constructor Details

#initialize(args) ⇒ File

Returns a new instance of File.



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# File 'lib/simple_iterator/file.rb', line 3

def initialize(args)
  increment_lines   = args[:increment_lines]  || raise('increment_lines is required')
  @file_path        = args[:file_path]        || raise('file_path is required')
  @separate         = args[:separate]         || "\t"
  @skip_headers     = args[:skip_headers]     || false
  @line_separate_cb = args[:line_separate_cb] || lambda { |row| row }
  @fh               = ::File.open(@file_path, 'rb:UTF-8:UTF-8', undef: :replace)

  next_cb = lambda { |offset|
    @fh.gets if offset == 0 && @skip_headers

    data = []
    (0 .. increment_lines - 1).each do
      line = @fh.gets
      line.chomp! if !line.nil? && line.length > 0

      break if line.nil?

      row = @line_separate_cb.call(line.split(@separate))

      data.push(row)
    end

    data.length > 0 ? data : nil
  }

  super(
    next_cb:          next_cb,
    increment_offset: increment_lines,
    offset:           0
  )
end