Contents

module CSVImporter

  # Reads, sanitize and parse a CSV file
  class CSVReader
    include Virtus.model

    attribute :content, String
    attribute :file # IO
    attribute :path, String
    attribute :quote_char, String, default: '"'

    def csv_rows
      @csv_rows ||= begin
        sane_content = sanitize_content(read_content)
        separator = detect_separator(sane_content)
        cells = CSV.parse(sane_content, col_sep: separator, quote_char: quote_char, skip_blanks: true)
        sanitize_cells(cells)
      end
    end

    # Returns the header as an Array of Strings
    def header
      @header ||= csv_rows.first
    end

    # Returns the rows as an Array of Arrays of Strings
    def rows
      @rows ||= csv_rows[1..-1]
    end

    private

    def read_content
      if content
        content
      elsif file
        file.read
      elsif path
        File.open(path).read
      else
        raise Error, "Please provide content, file, or path"
      end
    end

    def sanitize_content(csv_content)
      csv_content
        .encode(Encoding.find('UTF-8'), {invalid: :replace, undef: :replace, replace: ''}) # Remove invalid byte sequences
        .gsub(/\r\r?\n?/, "\n") # Replaces windows line separators with "\n"
    end

    SEPARATORS = [",", ";", "\t"]

    def detect_separator(csv_content)
      SEPARATORS.sort_by { |separator| csv_content.count(separator) }.last
    end

    # Remove trailing white spaces and ensure we always return a string
    def sanitize_cells(rows)
      rows.map do |cells|
        cells.map do |cell|
          cell ? cell.strip : ""
        end
      end
    end
  end
end

Version data entries

1 entries across 1 versions & 1 rubygems

Version	Path
csv-importer-0.3.0	lib/csv_importer/csv_reader.rb