From 203932ec88974acf8d86541cf0357cf9fc013143 Mon Sep 17 00:00:00 2001 From: Michael Koziarski Date: Tue, 27 Feb 2007 23:16:06 +0000 Subject: Add File.atomic_write to prevent users from seeing half written files. Useful for situations like Page Caching and the like. [Koz] git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@6262 5ecf4fe2-1ee6-0310-87b1-e25e094e27de --- activesupport/lib/active_support/core_ext/file.rb | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) create mode 100644 activesupport/lib/active_support/core_ext/file.rb (limited to 'activesupport/lib') diff --git a/activesupport/lib/active_support/core_ext/file.rb b/activesupport/lib/active_support/core_ext/file.rb new file mode 100644 index 0000000000..cd43be37e3 --- /dev/null +++ b/activesupport/lib/active_support/core_ext/file.rb @@ -0,0 +1,21 @@ +require 'tempfile' + +# Write to a file atomically. Useful for situations where you don't +# want other processes or threads to see half-written files. +# +# File.atomic_write("important.file") do |file| +# file.write("hello") +# end +# +# If your temp directory is not on the same filesystem as the file you're +# trying to write, you can provide a different temporary directory. +# +# File.atomic_write("/data/something.imporant", "/data/tmp") do |f| +# file.write("hello") +# end +def File.atomic_write(file_name, temp_dir = Dir.tmpdir) + temp_file = Tempfile.new(File.basename(file_name), temp_dir) + yield temp_file + temp_file.close + File.rename(temp_file.path, file_name) +end \ No newline at end of file -- cgit v1.2.3