Module: Xively::Parsers::CSV::DatastreamDefaults

Included in:
Datastream
Defined in:
lib/xively-rb/parsers/csv/datastream_defaults.rb

Instance Method Summary collapse

Instance Method Details

#from_csv(csv, csv_version = nil) ⇒ Object

Raises:



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# File 'lib/xively-rb/parsers/csv/datastream_defaults.rb', line 5

def from_csv(csv, csv_version = nil)
  begin
    rows = Xively::CSV.parse(csv.strip)
  rescue Exception => e
    # this might be a FasterCSV or CSV exception depending on whether
    # we are running under 1.8.x or 1.9.x
    raise InvalidCSVError, e.message
  end

  version = FeedDefaults.detect_version(rows, csv_version)

  raise InvalidCSVError, "CSV is invalid. Submitted data appears to be empty" if rows.nil?

  if version == :v1
    raise InvalidCSVError, "CSV is invalid. Can only construct a Xively::Datastream object from a single row of data" if rows.size > 1
    row = rows.first
    raise InvalidCSVError, "CSV is invalid. Too many fields; must only be a single value" if row.size > 1
    return { "current_value" => row[0].to_s.strip }
  else
    row_sizes = rows.collect { |row| row.size }.uniq
    raise InvalidCSVError, "CSV is invalid. Too many fields; must only be a single value, or a timestamp and a value" if row_sizes.max > 2

    if rows.size == 1
      # capture single lines (normal case)
      row = rows.first

      if row.size == 2
        return { "updated" => row[0].to_s.strip, "current_value" => row[1].to_s.strip }
      else
        return { "current_value" => row[0].to_s.strip }
      end
    else
      # capture multiple lines
      raise InvalidCSVError, "CSV is invalid. If multiple values are included, then a timestamp and value must be submitted for every row" if row_sizes.min < 2

      return { "datapoints" => rows.collect { |row| { "at" => row[0].to_s.strip, "value" => row[1].to_s.strip } } }
    end
  end

end