Subexec

by Peter Kieltyka http://github/nulayer/subexec

Description

Subexec is a simple library that spawns an external command with an optional timeout parameter. It relies on Ruby 1.9's Process.spawn method. Also, it works with synchronous and asynchronous code.

Useful for libraries that are Ruby wrappers for CLI's. For example, resizing images with ImageMagick's mogrify command sometimes stalls and never returns control back to the original process. Enter Subexec.

Tested with MRI 1.9.3, 1.9.2, 1.8.7

Usage

sub = Subexec.run "echo 'hello' && sleep 3", :timeout => 5
puts sub.output     # returns: hello
puts sub.exitstatus # returns: 0

sub = Subexec.run "echo 'hello' && sleep 3", :timeout => 1
puts sub.output     # returns: 
puts sub.exitstatus # returns:`

Limitations

Only Ruby 1.9 can spawn non-blocking subprocesses, via Process.spawn. So Ruby 1.8 support is sheerly for backwards compatibility.