Merge branch 'jbrady42-handler_queue_config'

Author: michaelklishin

examples/max_retry_handler.rb

@@ -33,12 +33,7 @@
 #
 class MaxRetryWorker
   include Sneakers::Worker
-  from_queue 'downloads',
-      WORKER_OPTIONS.merge({
-                             :arguments => {
-                               :'x-dead-letter-exchange' => 'downloads-retry'
-                             },
-                           })
+  from_queue 'downloads', WORKER_OPTIONS
 
   def work(msg)
     logger.info("MaxRetryWorker rejecting msg: #{msg.inspect}")
@@ -52,12 +47,7 @@ def work(msg)
 # see the message once.
 class SucceedingWorker
   include Sneakers::Worker
-  from_queue 'uploads',
-      WORKER_OPTIONS.merge({
-                             :arguments => {
-                               :'x-dead-letter-exchange' => 'uploads-retry'
-                             },
-                           })
+  from_queue 'uploads', WORKER_OPTIONS
 
   def work(msg)
     logger.info("SucceedingWorker succeeding on msg: #{msg.inspect}")

lib/sneakers/handlers/maxretry.rb

@@ -82,6 +82,11 @@ def initialize(channel, queue, opts)
 
       end
 
+      def self.configure_queue(name, opts)
+        retry_name = opts.fetch(:retry_exchange, "#{name}-retry")
+        opts.merge(arguments: { "x-dead-letter-exchange": retry_name })
+      end
+
       def acknowledge(hdr, props, msg)
         @channel.acknowledge(hdr.delivery_tag, false)
       end

lib/sneakers/queue.rb

@@ -31,9 +31,12 @@ def subscribe(worker)
     routing_key = @opts[:routing_key] || @name
     routing_keys = [*routing_key]
 
-    # TODO: get the arguments from the handler? Retry handler wants this so you
-    # don't have to line up the queue's dead letter argument with the exchange
-    # you'll create for retry.
+    handler_klass = worker.opts[:handler] || Sneakers::CONFIG.fetch(:handler)
+    # Configure options if needed
+    if handler_klass.respond_to?(:configure_queue)
+      @opts[:queue_options] = handler_klass.configure_queue(@name, @opts[:queue_options])
+    end
+
     queue = @channel.queue(@name, @opts[:queue_options])
 
     if exchange_name.length > 0
@@ -50,7 +53,6 @@ def subscribe(worker)
     # has the same configuration as the worker. Also pass along the exchange and
     # queue in case the handler requires access to them (for things like binding
     # retry queues, etc).
-    handler_klass = worker.opts[:handler] || Sneakers::CONFIG.fetch(:handler)
     handler = handler_klass.new(@channel, queue, worker.opts)
 
     @consumer = queue.subscribe(block: false, manual_ack: @opts[:ack]) do | delivery_info, metadata, msg |