Module: HistoryFile

Defined in:
lib/history_file/history_file.rb,
lib/history_file/file_delegator.rb

Overview

Behaves like a ‘File` class and does some convenience stuff around a FileDelegator instance. It all revolves about defining a time offset. If however, you want to access different versions of a file, use it like this:

> f = HistoryFile[1.day.ago].new("/tmp/foo.txt", "w")
=> #<File:/tmp/2012.11.02-foo.txt>

The returned FileDelegator object supports all methods that File has, but adds a date prefix to those methods that revolve around a single file (reading, writing, etc.)

If a file for a given date is not available, HistoryFile falls back to the freshest file that is older than the given date.

> f = HistoryFile[3.days.ago].new("test.txt", "w")
=> #<File:./2012.11.12-test.txt>
> f.write("I am old")
=> 8
> f.close
=> nil
> HistoryFile[Date.today].read("test.txt")
=> "I am old"
> HistoryFile[10.days.ago].read("test.txt")
Errno::ENOENT: No such file or directory - ./2012.11.05-test.txt

Defined Under Namespace

Classes: FileDelegator

Class Method Summary collapse

Class Method Details

.[](offset) ⇒ Object 



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# File 'lib/history_file/history_file.rb', line 36

def self.[](offset)
  validate_offset(offset)
  use_subdirs = @mode == :subdir
  fallback_glob = "[0-9][0-9][0-9][0-9].[0-9][0-9].[0-9][0-9]"
  FileDelegator.new(prefix: prefix(offset),
                    fallback_glob: fallback_glob,
                    use_subdirs: use_subdirs)
end

.mode=(mode) ⇒ Object

Raises:

  • (ArgumentError) 


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# File 'lib/history_file/history_file.rb', line 30

def self.mode=(mode)
  return @mode = :filename if mode.to_sym == :filename
  return @mode = :subdir   if mode.to_sym == :subdir
  raise ArgumentError, "Mode must be :filename or :subdir"
end