Class: Cosmos::CSV

Inherits:
Object show all
Defined in:
lib/cosmos/utilities/csv.rb

Overview

Reads in a comma separated values (CSV) configuration file and allows access via the Hash bracket syntax. It allows the user to write back data to the configuration file to store state.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(input_file) ⇒ CSV

Returns a new instance of CSV.

Parameters:

  • input_file (String) —

    CSV file name to read



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# File 'lib/cosmos/utilities/csv.rb', line 23

def initialize(input_file)
  @filename = input_file
  @hash = {}
  @archive = nil
  @archive_file = ""
  Object::CSV.read(input_file).each do |line|
    @hash[line[0]] = line[1..-1].compact
  end
end

Instance Attribute Details

#archive_file ⇒ String (readonly)

Returns The name of the archive file.

Returns:

  • (String) —

    The name of the archive file



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# File 'lib/cosmos/utilities/csv.rb', line 20

def archive_file
  @archive_file
end

Instance Method Details

#[](index) ⇒ Array<String>

Returns The values in columns 2-n corresponding to the given key in column 1. The values are always returned as Strings so the user must convert if necessary.

Returns:

  • (Array<String>) —

    The values in columns 2-n corresponding to the given key in column 1. The values are always returned as Strings so the user must convert if necessary.



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# File 'lib/cosmos/utilities/csv.rb', line 42

def [](index)
  @hash[index]
end

#close_archive ⇒ Object

Closes the archive file created by ##create_archive. Once this method is called, #write_archive will throw an exception.



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# File 'lib/cosmos/utilities/csv.rb', line 77

def close_archive
  @archive.close
  @archive = nil
end

#create_archive(path = nil) ⇒ Object

Creates a copy of the CSV file passed into the constructor. The file will be prefixed by the current date and time to create a unique filename. By default this file is created in the COSMOS/logs directory. Subsequent calls to #write_archive will write to this file until #close_archive is called.

Parameters:

  • path (String) (defaults to: nil) —

    Path location to create the archive file. If nil the file will be created in COSMOS/logs.



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# File 'lib/cosmos/utilities/csv.rb', line 54

def create_archive(path = nil)
  raise "Archive file \"#{@archive.path}\" already open." unless @archive.nil?
  path = System.paths['LOGS'] if path.nil?
  @archive_file = File.join(path, File.build_timestamped_filename([File.basename(@filename)], ''))
  @archive = File.open(@archive_file,"w")
  @hash.each do |key, values|
    @archive.puts "#{key},#{values.join(',')}"
  end
  @archive.puts "\n"
end

#keys ⇒ Array<String>

Returns All the values in the first column of the CSV file. These values are used as keys to access the data in columns 2-n.

Returns:

  • (Array<String>) —

    All the values in the first column of the CSV file. These values are used as keys to access the data in columns 2-n.



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# File 'lib/cosmos/utilities/csv.rb', line 35

def keys
  @hash.keys
end

#write_archive(values) ⇒ Object

Write the archive file created by ##create_archive. This method will append a CSV row to the archive file by joining all the values in the array into a CSV entry.

Parameters:

  • values (Array) —

    Array of values which will go in columns 1-n



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# File 'lib/cosmos/utilities/csv.rb', line 70

def write_archive(values)
  raise "Archive file not opened! Call create_archive." if @archive.nil?
  @archive.puts values.join(',')
end