Allow Queue#pop to take an optional block

lib/bunny/queue08.rb

@@ -182,9 +182,12 @@ def delete(opts = {})
   :payload => :queue_empty
   :delivery_details => nil
 
+N.B. If a block is provided then the hash will be passed into the block and the return value
+will be nil.
+
 =end
 
-	  def pop(opts = {})
+	  def pop(opts = {}, &blk)
 
 			# do we want to have to provide an acknowledgement?
 			ack = opts.delete(:ack)
@@ -199,25 +202,32 @@ def pop(opts = {})
 			method = client.next_method
 
 			if method.is_a?(Qrack::Protocol::Basic::GetEmpty) then
-				return {:header => nil, :payload => :queue_empty, :delivery_details => nil}
+				queue_empty = true
 			elsif	!method.is_a?(Qrack::Protocol::Basic::GetOk)
 				raise Bunny::ProtocolError, "Error getting message from queue #{name}"
 			end
 
-			# get delivery tag to use for acknowledge
-			self.delivery_tag = method.delivery_tag if ack
+			if !queue_empty
+				# get delivery tag to use for acknowledge
+				self.delivery_tag = method.delivery_tag if ack
 
-	    header = client.next_payload
+		    header = client.next_payload
 
-	    # If maximum frame size is smaller than message payload body then message
-			# will have a message header and several message bodies
-			msg = ''
-			while msg.length < header.size
-				msg += client.next_payload
+		    # If maximum frame size is smaller than message payload body then message
+				# will have a message header and several message bodies
+				msg = ''
+				while msg.length < header.size
+					msg += client.next_payload
+				end
+
+				msg_hash = {:header => header, :payload => msg, :delivery_details => method.arguments}
+
+			else
+				msg_hash = {:header => nil, :payload => :queue_empty, :delivery_details => nil}
 			end
-
-			# Return message with additional info if requested
-			{:header => header, :payload => msg, :delivery_details => method.arguments}
+			
+			# Pass message hash to block or return message hash
+			blk ? blk.call(msg_hash) : msg_hash		
 
 	  end
 

lib/bunny/queue09.rb

@@ -183,9 +183,12 @@ def delete(opts = {})
   :payload => :queue_empty
   :delivery_details => nil
 
+N.B. If a block is provided then the hash will be passed into the block and the return value
+will be nil.
+
 =end
 
-	  def pop(opts = {})
+	  def pop(opts = {}, &blk)
 
 			# do we want to have to provide an acknowledgement?
 			ack = opts.delete(:ack)
@@ -201,26 +204,33 @@ def pop(opts = {})
 			method = client.next_method
 
 			if method.is_a?(Qrack::Protocol09::Basic::GetEmpty) then
-				return {:header => nil, :payload => :queue_empty, :delivery_details => nil}
+				queue_empty = true
 			elsif	!method.is_a?(Qrack::Protocol09::Basic::GetOk)
 				raise Bunny::ProtocolError, "Error getting message from queue #{name}"
 			end
-
-			# get delivery tag to use for acknowledge
-			self.delivery_tag = method.delivery_tag if ack
-
-	    header = client.next_payload
-
-	    # If maximum frame size is smaller than message payload body then message
-			# will have a message header and several message bodies
-			msg = ''
-			while msg.length < header.size
-				msg += client.next_payload
+
+			if !queue_empty
+				# get delivery tag to use for acknowledge
+				self.delivery_tag = method.delivery_tag if ack
+
+		    header = client.next_payload
+
+		    # If maximum frame size is smaller than message payload body then message
+				# will have a message header and several message bodies
+				msg = ''
+				while msg.length < header.size
+					msg += client.next_payload
+				end
+
+				msg_hash = {:header => header, :payload => msg, :delivery_details => method.arguments}
+
+			else
+				msg_hash = {:header => nil, :payload => :queue_empty, :delivery_details => nil}
 			end
 
-			# Return message with additional info if requested
-			{:header => header, :payload => msg, :delivery_details => method.arguments}
-			
+			# Pass message hash to block or return message hash
+			blk ? blk.call(msg_hash) : msg_hash		
+
 	  end
 
 =begin rdoc

spec/spec_08/exchange_spec.rb

@@ -8,7 +8,7 @@
 
 require File.expand_path(File.join(File.dirname(__FILE__), %w[.. .. lib bunny]))
 
-describe Bunny do
+describe 'Exchange' do
 
 	before(:each) do
     @b = Bunny.new

spec/spec_08/queue_spec.rb

@@ -8,7 +8,7 @@
 
 require File.expand_path(File.join(File.dirname(__FILE__), %w[.. .. lib bunny]))
 
-describe Bunny do
+describe 'Queue' do
 
 	before(:each) do
     @b = Bunny.new
@@ -87,6 +87,13 @@
 		msg.should == lg_msg
 	end
 
+	it "should be able call a block when popping a message" do
+		q = @b.queue('test1')
+		q.publish('This is another test message')
+		q.pop { |msg| msg[:payload].should == 'This is another test message' }
+		q.pop { |msg| msg[:payload].should == :queue_empty }
+	end
+
 	it "should raise an error if purge fails" do
 		q = @b.queue('test1')
 		5.times {q.publish('This is another test message')}

spec/spec_09/exchange_spec.rb

@@ -8,7 +8,7 @@
 
 require File.expand_path(File.join(File.dirname(__FILE__), %w[.. .. lib bunny]))
 
-describe Bunny do
+describe 'Exchange' do
 
 	before(:each) do
     @b = Bunny.new(:spec => '09')

spec/spec_09/queue_spec.rb

@@ -8,7 +8,7 @@
 
 require File.expand_path(File.join(File.dirname(__FILE__), %w[.. .. lib bunny]))
 
-describe Bunny do
+describe 'Queue' do
 
 	before(:each) do
     @b = Bunny.new(:spec => '09')
@@ -87,6 +87,13 @@
 		msg.should == lg_msg
 	end
 
+	it "should be able call a block when popping a message" do
+		q = @b.queue('test1')
+		q.publish('This is another test message')
+		q.pop { |msg| msg[:payload].should == 'This is another test message' }
+		q.pop { |msg| msg[:payload].should == :queue_empty }
+	end
+
 	it "should raise an error if purge fails" do
 		q = @b.queue('test1')
 		5.times {q.publish('This is another test message')}