init.rb lib/worker_queue/worker_queue.rb lib/worker_queue/worker_queue_item.rb lib/worker_queue/worker_tester.rb spec/models/worker_queue_spec.rb spec/rcov.opts spec/spec.opts spec/spec_helper.rb tasks/worker_queue.rake @@ -0,0 +1,79 @@ +Bart ten Brinke - Nedap healthcare - 2008 + +----------- +Description +----------- +As I found things like background rb to unstable or to memory hogging, I decided to make this. +It is a very simple task scheduler for rails. + + +----------- +Installation +----------- + +git clone git://github.com/barttenbrinke/worker_queue.git vendor/plugins/worker_queue + + +----------- +Usage +----------- +Whenever you want to background a task, just do the following: + work = WorkerQueue::WorkerQueueItem.new + work.class_name = 'Someclass' + work.method_name = 'somemethod' + work.argument_hash = {:monkey => :tail} + work.binary_data = '1234567890' + work.save! + +This will be picked up by the worker when the following command is called: + WorkerQueue.work + + Which in turn will call: + Someclass.somemethod({:monkey => :tail, :binary_data => '1234567890') + +It is advised set up a cronjob that runs the supplied rake task: + rake worker_queue:work + +Note that workerqueue will run only one task of a single class at the same time. +So if you want to queue a execute the items one after the other, make sure all items are set +to the same class. +This is also very usefull for things like uploaded files that need to be handled in the order in which +they were uploaded. + +If you just want to execute items in the background, enter a unique classname for each item and +WorkerQueue will try its best to complete. + +After the workerqueue has executed a task successfully, it will clear the binary (if any) and move on +to the next item. WorkerQueue has no problem with multiple instances of it being run a the same time. + +Use the following migration to get the show on the road: + +class CreateWorkerQueueItems < ActiveRecord::Migration + def self.up + create_table :worker_queue_items, :options => 'ENGINE=InnoDB DEFAULT CHARSET=UTF8' do |t| + t.column :task_name, :string + t.column :task_group, :string + t.column :class_name, :string + t.column :method_name, :string + t.column :argument_hash, :text + t.column :binary_data, :binary + t.column :running, :boolean, :default => 0 + t.column :completed, :boolean, :default => 0 + t.column :error, :boolean, :default => 0 + t.column :error_message, :string + end + end + + def self.down + drop_table :worker_queue_items + end +end + + +----------- +Final Notes +----------- +- The specs only run in a rails project with the WorkerQueue plugin installed. This needs fixing. +- If you want to store big files in the binary_data field, make sure you MYSQL config accepts inserts that are big enough. +- That the tasks that get executed expect a Class.method(args_hash, binary_blob) that returns true +or false. \ No newline at end of file README 4a1e56a561c498debe908c9db497c00dc9e7a4e6 Bart ten Brinke bart@nvc1058.local http://github.com/barttenbrinke/worker_queue/commit/ecf4b4e91d6a8afc0656a221ae77234a975348e8 ecf4b4e91d6a8afc0656a221ae77234a975348e8 2008-08-13T11:35:16-07:00 2008-08-13T11:35:16-07:00 First WorkerQueue commit 8a6a550f836aa26af53764f61d41d98a53fd0f19 Bart ten Brinke bart@nvc1058.local