Class: LogicalConstruct::Target::FlightDeck::UniqueProcessTask

Inherits:
Mattock::Rake::Task
  • Object
show all
Defined in:
lib/logical-construct/target/flight-deck.rb

Instance Method Summary collapse

Instance Method Details

#action(args) ⇒ Object 



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# File 'lib/logical-construct/target/flight-deck.rb', line 119

def action(args)
  require 'pathname'
  Pathname.new(lockdir.absolute_path).mkpath
  File::open(lockfile.absolute_path, File::CREAT|File::EXCL|File::WRONLY, 0600) do |file|
    file.write(Process.pid)
  end
  at_exit{ File::unlink(lockfile.absolute_path) }
rescue Errno::EEXIST
  pid = File::open(lockfile.absolute_path, File::RDONLY) do |file|
    file.read.to_i
  end
  begin
    Process.kill(0, pid)
    puts "Another process (pid: #{pid}) already owns #{lockfile.absolute_path}"
    puts "Exiting"
    exit(1)
  rescue Errno::ESRCH, RangeError
    #process doesn't exist
    File::unlink(lockfile.absolute_path)
  end
  retry #if we get here it's because the previous process is dead and we've cleaned up
end

#resolve_configuration ⇒ Object 



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# File 'lib/logical-construct/target/flight-deck.rb', line 113

def resolve_configuration
  lockfile.relative_path ||= [task_name, "lock"].join(".")
  resolve_paths
  super
end