Nov 30
Clockwork and delayed job and PostgreSQL
Clockwork is simple and very useful tool for scheduling tasks instead of using cron jobs in ruby.
First things first, add clockwork to your Gemfile:
gem 'clockwork'Configuration is kept in config/clock.rb. It uses plain ruby DSL. Most amazing thing is to use custom handler which allows you to skip loading Rails environment and insert scheduled jobs directly into delyed job database table.
# Clockfile require 'pg' require 'yaml' db = YAML.load_file(File.dirname(__FILE__) + "/database.yml")[ENV['RAILS_ENV'] || "development"] conn = PGconn.connect(db['host'], nil, nil, nil, db['database'], db['username'], db['password']) require 'clockwork' include Clockwork handler do |job| db_time = Time.now.utc.strftime("%Y-%m-%d %H:%M:%S") handler = "--- !ruby/object:ScheduledJob \njob: #{job}\n" conn.exec("INSERT INTO \"delayed_jobs\" (\"failed_at\", \"locked_by\", \"created_at\", \"handler\", \"updated_at\", \"priority\", \"run_at\", \"attempts\", \"locked_at\", \"last_error\") VALUES(NULL, NULL, '#{db_time}', '#{handler}', '#{db_time}', 0, '#{db_time}', 0, NULL, NULL)") end every(30.minutes, 'reactivate_paid_accounts') # and more every blocks with definitions
And finally example of ScheduledJob:
# app/workers/scheduled_job.rb class ScheduledJob attr_accessor :job SUPPORTED_JOBS = { :reactivate_paid_accounts => 'Account.reactivate_paid' } def initialize(job) self.job = job unless SUPPORTED_JOBS.has_key?(job.to_sym) raise "Unsupported scheduled action - #{job}" end end def perform klass, method = SUPPORTED_JOBS[job.to_sym].split('.') Kernel.const_get(klass).send(method.to_sym) end def display_name "Job/#{job}" end end
