diff options
| -rw-r--r-- | activesupport/lib/active_support/core_ext/file.rb | 24 | ||||
| -rw-r--r-- | activesupport/lib/active_support/core_ext/file/atomic.rb | 46 | ||||
| -rw-r--r-- | activesupport/test/core_ext/file_test.rb | 50 |
3 files changed, 94 insertions, 26 deletions
diff --git a/activesupport/lib/active_support/core_ext/file.rb b/activesupport/lib/active_support/core_ext/file.rb index 45d93b220f..e03f8ac44e 100644 --- a/activesupport/lib/active_support/core_ext/file.rb +++ b/activesupport/lib/active_support/core_ext/file.rb @@ -1,21 +1,5 @@ -require 'tempfile' +require 'active_support/core_ext/file/atomic' -# 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.important", "/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 +class File #:nodoc: + extend ActiveSupport::CoreExtensions::File::Atomic +end diff --git a/activesupport/lib/active_support/core_ext/file/atomic.rb b/activesupport/lib/active_support/core_ext/file/atomic.rb new file mode 100644 index 0000000000..4d3cf5423f --- /dev/null +++ b/activesupport/lib/active_support/core_ext/file/atomic.rb @@ -0,0 +1,46 @@ +require 'tempfile' + +module ActiveSupport #:nodoc: + module CoreExtensions #:nodoc: + module File #:nodoc: + module Atomic + # 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.important", "/data/tmp") do |f| + # file.write("hello") + # end + def atomic_write(file_name, temp_dir = Dir.tmpdir) + temp_file = Tempfile.new(basename(file_name), temp_dir) + yield temp_file + temp_file.close + + begin + # Get original file permissions + old_stat = stat(file_name) + rescue Errno::ENOENT + # No old permissions, write a temp file to determine the defaults + check_name = ".permissions_check.#{Thread.current.object_id}.#{Process.pid}.#{rand(1000000)}" + new(check_name, "w") + old_stat = stat(check_name) + unlink(check_name) + end + + # Overwrite original file with temp file + rename(temp_file.path, file_name) + + # Set correct permissions on new file + chown(old_stat.uid, old_stat.gid, file_name) + chmod(old_stat.mode, file_name) + end + end + end + end +end diff --git a/activesupport/test/core_ext/file_test.rb b/activesupport/test/core_ext/file_test.rb index 5efe357e9f..63b470684f 100644 --- a/activesupport/test/core_ext/file_test.rb +++ b/activesupport/test/core_ext/file_test.rb @@ -1,9 +1,8 @@ require 'abstract_unit' class AtomicWriteTest < Test::Unit::TestCase - def test_atomic_write_without_errors - contents = "Atomic Text" + contents = "Atomic Text" File.atomic_write(file_name, Dir.pwd) do |file| file.write(contents) assert !File.exist?(file_name) @@ -13,7 +12,7 @@ class AtomicWriteTest < Test::Unit::TestCase ensure File.unlink(file_name) rescue nil end - + def test_atomic_write_doesnt_write_when_block_raises File.atomic_write(file_name) do |file| file.write("testing") @@ -22,8 +21,47 @@ class AtomicWriteTest < Test::Unit::TestCase rescue assert !File.exist?(file_name) end - - def file_name - "atomic.file" + + def test_atomic_write_preserves_file_permissions + contents = "Atomic Text" + File.open(file_name, "w", 0755) do |file| + file.write(contents) + assert File.exist?(file_name) + end + assert File.exist?(file_name) + assert_equal "100755", file_mode + assert_equal contents, File.read(file_name) + + File.atomic_write(file_name, Dir.pwd) do |file| + file.write(contents) + assert File.exist?(file_name) + end + assert File.exist?(file_name) + assert_equal "100755", file_mode + assert_equal contents, File.read(file_name) + ensure + File.unlink(file_name) rescue nil + end + + def test_atomic_write_preserves_default_file_permissions + contents = "Atomic Text" + File.atomic_write(file_name, Dir.pwd) do |file| + file.write(contents) + assert !File.exist?(file_name) + end + assert File.exist?(file_name) + assert_equal "100644", file_mode + assert_equal contents, File.read(file_name) + ensure + File.unlink(file_name) rescue nil end + + private + def file_name + "atomic.file" + end + + def file_mode + sprintf("%o", File.stat(file_name).mode) + end end |