Class: IOStreams::Row::Reader

Inherits:
IOStreams::Reader show all
Defined in:
lib/io_streams/row/reader.rb

Overview

Converts each line of an input stream into an array for every line

Instance Attribute Summary

Attributes inherited from IOStreams::Reader

#input_stream

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from IOStreams::Reader

open

Constructor Details

#initialize(line_reader, cleanse_header: true, original_file_name: nil, **args) ⇒ Reader

Create a Tabular reader to return the stream rows as arrays.

Parameters

delimited: [#each]
  Anything that returns one line / record at a time when #each is called on it.

format: [Symbol]
  :csv, :hash, :array, :json, :psv, :fixed

For all other parameters, see Tabular::Header.new



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# File 'lib/io_streams/row/reader.rb', line 32

def initialize(line_reader, cleanse_header: true, original_file_name: nil, **args)
  unless line_reader.respond_to?(:each)
    raise(ArgumentError, "Stream must be a IOStreams::Line::Reader or implement #each")
  end

  @tabular        = IOStreams::Tabular.new(file_name: original_file_name, **args)
  @line_reader    = line_reader
  @cleanse_header = cleanse_header
end

Class Method Details

.file(file_name, original_file_name: file_name, delimiter: $/, **args) ⇒ Object

When reading from a file also add the line reader stream



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# File 'lib/io_streams/row/reader.rb', line 16

def self.file(file_name, original_file_name: file_name, delimiter: $/, **args)
  IOStreams::Line::Reader.file(file_name, original_file_name: original_file_name, delimiter: delimiter) do |io|
    yield new(io, original_file_name: original_file_name, **args)
  end
end

.stream(line_reader, **args) {|new(line_reader, **args)| ... } ⇒ Object

Read a line as an Array at a time from a stream. Note:

  • The supplied stream must already be a line stream, or a stream that responds to :each

Yields:

  • (new(line_reader, **args)) 


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# File 'lib/io_streams/row/reader.rb', line 8

def self.stream(line_reader, **args)
  # Pass-through if already a row reader
  return yield(line_reader) if line_reader.is_a?(self.class)

  yield new(line_reader, **args)
end

Instance Method Details

#each ⇒ Object 



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# File 'lib/io_streams/row/reader.rb', line 42

def each
  @line_reader.each do |line|
    if @tabular.header?
      columns = @tabular.parse_header(line)
      @tabular.cleanse_header! if @cleanse_header
      yield columns
    else
      yield @tabular.row_parse(line)
    end
  end
end