git.oblomov.eu Git - ohcount/blob - lib/ohcount/scratch_dir.rb

   1 require 'fileutils'
   2 require 'tmpdir'
   3
   4 # A utility class to manage the creation and automatic cleanup of temporary directories.
   5 class ScratchDir
   6         attr_reader :path
   7
   8         # Creates a uniquely named directory in the system tmp directory.
   9         #
  10         # If a block is passed to the constructor, the path to the created directory
  11         # will be yielded to the block. The directory will then be deleted
  12         # when this block returns.
  13         #
  14         # Sample usage:
  15         #
  16         #   ScratchDir.new do |path|
  17         #     # Do some work in the new directory
  18         #     File.new( path + '/foobaz', 'w' ) do
  19         #       # ...
  20         #     end
  21         #   end # Scratch directory is deleted here
  22         #
  23         def initialize
  24                 until @path
  25                         @path = File.join(Dir.tmpdir, Time.now.utc.strftime("ohloh_%Y%H%m%S#{rand(900) + 100}"))
  26                         begin
  27                                 Dir.mkdir(@path)
  28                         rescue Errno::EEXIST
  29                                 @path = nil
  30                         end
  31                 end
  32                 if block_given?
  33                         yield @path
  34                         FileUtils.rm_rf(@path)
  35                 end
  36         end
  37 end
  38
  39 if $0 == __FILE__
  40         path = nil
  41         ScratchDir.new do |d|
  42                 path = d
  43                 STDOUT.puts "Created scratch direcory #{d}"
  44                 File.open(File.join(d, "test"), "w") do |io|
  45                         io.write "test"
  46                 end
  47         end
  48         raise RuntimeError.new("Directory wasn't cleaned up") if FileTest.directory?(path)
  49         STDOUT.puts "Test passed."
  50 end