README.md in worker_roulette-0.0.6 vs README.md in worker_roulette-0.0.7

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@@ -2,39 +2,71 @@ WorkerRoulette is designed to allow large numbers of unique devices, processes, users, or whatever communicate over individual channels without messing up the order of their messages. WorkerRoulette was created to solve two otherwise hard problems. First, other messaging solutions (I'm looking at you RabbitMQ) are not designed to handle very large numbers of queues (30,000+); because WorkerRoulette is built on top of Redis, we have successfully tested it running with millions of queues. Second, other messaging systems assume one (or more) of three things: 1. Your message consumers know the routing key of messages they are interested in processing; 2. Your messages can wait so that only one consumer is processed at a time; 3. You love to complicated write code to put your messages back in order. Sometimes, none of these things is true and that is where WorkerRoulette comes in. WorkerRoulette lets you have thousands of competing consumers (distrubted over as many machines as you'd like) processing ordered messages from millions of totally unknown message providers. It does all this and ensures that the messages sent from each message provider are processed in exactly the order it sent them. -## Usage - size_of_connection_pool = 100 - redis_config = {host: 'localhost', timeout: 5, db: 1} +## General Usage +```ruby +size_of_connection_pool = 100 +redis_config = {host: 'localhost', timeout: 5, db: 1} - WorkerRoulette.start(size_of_connection_pool, redis_config) +#Start it up +WorkerRoulette.start(size_of_connection_pool, redis_config) - sender_id = :shady - foreman = WorkerRoulette.foreman(sender_id) - foreman.enqueue_work_order(['hello', 'foreman']) +#Enqueue some work +sender_id = :shady +foreman = WorkerRoulette.foreman(sender_id) +foreman.enqueue_work_order(['hello', 'foreman']) - tradesman = WorkerRoulette.tradesman - messages = tradesman.work_orders! #drain the queue of the next available sender - messages.first # => ['hello', 'foreman'] +#Pull it off +tradesman = WorkerRoulette.tradesman +messages = tradesman.work_orders! #drain the queue of the next available sender +messages.first # => ['hello', 'foreman'] - other_sender_id = :the_real_slim_shady - other_foreman = WorkerRoulette.foreman(other_sender_id) - other_foreman.enqueue_work_order({'can you get me' => 'the number nine?'}) +#Enqueue some more from someone else +other_sender_id = :the_real_slim_shady +other_foreman = WorkerRoulette.foreman(other_sender_id) +other_foreman.enqueue_work_order({'can you get me' => 'the number nine?'}) - messages = tradesman.work_orders! #drain the queue of the next available sender - messages.first # => {'can you get me' => 'the number nine?'} +#Have the same worker pull that off +messages = tradesman.work_orders! #drain the queue of the next available sender +messages.first # => {'can you get me' => 'the number nine?'} - on_subscribe_callback = -> do - puts "Huzzah! We're listening!" - foreman.enqueue_work_order('will I see you later?') - foreman.enqueue_work_order('can you give me back my dime?') - end +#Have your workers wait for work to come in +on_subscribe_callback = -> do + puts "Huzzah! We're listening!" + foreman.enqueue_work_order('will I see you later?') + foreman.enqueue_work_order('can you give me back my dime?') +end - tradesman.wait_for_work_orders(on_subscribe_callback) do |messages| #drain the queue of the next available sender - messages # => ['will I see you later', 'can you give me back my dime?'] - end + +#And they will pull it off as it comes, as long as it comes +#(This is a blocking operation, so it is best in Threads or EventMachine.next_tick) +tradesman.wait_for_work_orders(on_subscribe_callback) do |messages| #drain the queue of the next available sender + messages # => ['will I see you later', 'can you give me back my dime?'] +end +``` + +## Channels +You can also namespace your work orders over a channel, in case you have several sorts of competing consumers who should not step on each other's toes: +```ruby +tradesman = WorkerRoulette.tradesman('good_channel') +tradesman.should_receive(:work_orders!).and_call_original + +good_foreman = WorkerRoulette.foreman('foreman', 'good_channel') +bad_foreman = WorkerRoulette.foreman('foreman', 'bad_channel') + +publish = -> do + good_foreman.enqueue_work_order('some old fashion work') + bad_foreman.enqueue_work_order('evil biddings you should not carry out') #channels let us ignore his evil orders +end + +tradesman.wait_for_work_orders(publish) do |work| + work.to_s.should match("some old fashion work") #only got the work from the good foreman + tradesman.unsubscribe +end + +``` ##Caveat Emptor While WorkerRoulette does promise to keep the messages of each consumer processed in order by competing consumers, it does NOT guarantee the order in which the queues themselves will be processed. In general, work is processed in a FIFO order, but for performance reasons this has been left a loose FIFO. For example, if Abdul enqueue_work_orders some ordered messages ('1', '2', and '3') and then so do Mark and Wanda, Mark's messages may be processed first, then it would likely be Abdul's, and then Wanda's. However, even though Mark jumped the line, Abdul's messages will still be processed the order he enqueue_work_orderd them ('1', '2', then '3'). ## Installation