Class: File

Inherits:
Object show all
Defined in:
lib/iron/extensions/file.rb

Class Method Summary collapse

Class Method Details

.safe_replace(path, perm = nil) ⇒ Object

Atomic replace code - write to temp file, rename to source file path only after successful completion of block. Prevents partial writes from overwriting files.

Usage:

File.safe_replace(‘/etc/foo.conf’) do |file|

file.write('bob=1234')

end



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# File 'lib/iron/extensions/file.rb', line 13

def self.safe_replace(path, perm = nil) # :yields: file
  begin
    tmp_path = path + '.tmp' + Kernel.rand(999999).to_s
  end while File.exist?(tmp_path)

  file = File.open(tmp_path, 'w', perm)
  yield file
  file.close

  FileUtils.mv(tmp_path, path)
ensure
  # Close file if needed
  file.close unless file.closed?
  
  # Clean up temp file
  File.unlink(tmp_path) if File.exists?(tmp_path)
end