You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

81 lines
2.8 KiB

# A way to cleanly handle process forking in Sinatra when using Passenger, aka "sporking some code".
# This will allow you to properly execute some code asynchronously, which otherwise does not work correctly.
#
# Written by Ron Evans
# More info at http://deadprogrammersociety.com
#
# Mostly lifted from the Spawn plugin for Rails (http://github.com/tra/spawn)
# but with all of the Rails stuff removed.... cause you are using Sinatra. If you are using Rails, Spawn is
# what you need. If you are using something else besides Sinatra that is Rack-based under Passenger, and you are having trouble with
# asynch processing, let me know if spork helped you.
#
module Spork
# things to close in child process
@@resources = []
def self.resources
@@resources
end
# set the resource to disconnect from in the child process (when forking)
def self.resource_to_close(resource)
@@resources << resource
end
# close all the resources added by calls to resource_to_close
def self.close_resources
@@resources.each do |resource|
resource.close if resource && resource.respond_to?(:close) && !resource.closed?
end
@@resources = []
end
# actually perform the fork... er, spork
# valid options are:
# :priority => to set the process priority of the child
# :logger => a logger object to use from the child
# :no_detach => true if you want to keep the child process under the parent control. usually you do NOT want this
def self.spork(options = {})
logger = options[:logger]
logger.debug "spork> parent PID = #{Process.pid}" if logger
child = fork do
begin
start = Time.now
logger.debug "spork> child PID = #{Process.pid}" if logger
# set the nice priority if needed
Process.setpriority(Process::PRIO_PROCESS, 0, options[:priority]) if options[:priority]
# disconnect from the rack
Spork.close_resources
# run the block of code that takes so long
yield
rescue => ex
logger.error "spork> Exception in child[#{Process.pid}] - #{ex.class}: #{ex.message}" if logger
ensure
logger.info "spork> child[#{Process.pid}] took #{Time.now - start} sec" if logger
# this form of exit doesn't call at_exit handlers
exit!(0)
end
end
# detach from child process (parent may still wait for detached process if they wish)
Process.detach(child) unless options[:no_detach]
return child
end
end
# Patch to work with passenger
if defined? Passenger::Rack::RequestHandler
class Passenger::Rack::RequestHandler
alias_method :orig_process_request, :process_request
def process_request(env, input, output)
Spork.resource_to_close(input)
Spork.resource_to_close(output)
orig_process_request(env, input, output)
end
end
end