如何暂停和恢复兔子的消费

Question

有什么方法暂时暂停消费者，并在稍后恢复？

这里是我想要做的一个例子：

require "bunny" 
conn = Bunny.new 
conn.start 

ch1 = conn.create_channel 
publisher = ch.direct('test', :auto_delete => false) 

consumer1 = nil 
Thread.new do 
    ch2 = conn.create_channel(nil, 8) #Using eight worker 
    queue1 = ch2.queue('', :exclusive => true) 
    queue1.bind(publisher, :routing_key => 'low_priority') 
    consumer1 = queue1.subscribe(:block => true) do |delivery_info, properties, payload| 
     #do some work 
    end 
end 

Thread.new do 
    ch3 = conn.create_channel 
    queue2 = ch3.queue('', :exclusive => true) 
    queue2.bind(publisher, :routing_key => 'high_priority') 
    consumer2 = queue2.subscribe(:block => true) do |delivery_info, properties, payload| 
     consumer1.pause #pause the other consumer 
     #do other things 
     consumer1.resume #resume the consumer 
    end 
end 
#rest of the code 

我想暂停时，我做的consumer2工作consumer1。有没有任何有效的方法来做到这一点？

Answer 1

如果你想创建优先政策，兔子已经实现了这个：

http://rubybunny.info/articles/queues.html#consumer_priorities

q = ch.queue("a.queue") 
q.subscribe(:manual_ack => true, :arguments => {"x-priority" => 5}) do |delivery_info, properties, payload| 
    # ... 
end 
q.subscribe(:manual_ack => true, :arguments => {"x-priority" => 2}) do |delivery_info, properties, payload| 
    # ... 
end 

如果你要处理它在并行我建议这种宝石：

https://github.com/grosser/parallel

示例：

results = Parallel.map(['a','b','c'], in_processes: 3) { |one_letter| ... } 

希望它有帮助。