Use shared concurrency for performance / simplicity

Fixes #71

CHANGELOG.md

@@ -1,3 +1,6 @@
+## 5.1.0
+  _ Use shared concurrency / multiple channels for performance
+
 ## 5.0.3
   - Update gemspec summary
 

lib/logstash/outputs/rabbitmq.rb

@@ -17,6 +17,8 @@ class RabbitMQ < LogStash::Outputs::Base
       include LogStash::PluginMixins::RabbitMQConnection
 
       config_name "rabbitmq"
+
+      concurrency :shared
 
       # The default codec for this plugin is JSON. You can override this to suit your particular needs however.
       default :codec, "json"
@@ -44,22 +46,24 @@ class RabbitMQ < LogStash::Outputs::Base
       def register
         connect!
         @hare_info.exchange = declare_exchange!(@hare_info.channel, @exchange, @exchange_type, @durable)
-        @codec.on_event(&method(:publish))
+        # The connection close should close all channels, so it is safe to store thread locals here without closing them
+        @thread_local_channel = java.lang.ThreadLocal.new
+        @thread_local_exchange = java.lang.ThreadLocal.new
       end
 
       def symbolize(myhash)
         Hash[myhash.map{|(k,v)| [k.to_sym,v]}]
       end
 
-      def receive(event)
-        @codec.encode(event)
-      rescue StandardError => e
-        @logger.warn("Error encoding event", :exception => e, :event => event)
+      def multi_receive_encoded(events_and_data)
+        events_and_data.each do |event, data|
+          publish(event, data)
+        end
       end
 
       def publish(event, message)
         raise ArgumentError, "No exchange set in HareInfo!!!" unless @hare_info.exchange
-        @hare_info.exchange.publish(message, :routing_key => event.sprintf(@key), :properties => symbolize(@message_properties.merge(:persistent => @persistent)))
+        local_exchange.publish(message, :routing_key => event.sprintf(@key), :properties => symbolize(@message_properties.merge(:persistent => @persistent)))
       rescue MarchHare::Exception, IOError, AlreadyClosedException, TimeoutException => e
         @logger.error("Error while publishing. Will retry.",
                       :message => e.message,
@@ -70,6 +74,24 @@ def publish(event, message)
         retry
       end
 
+      def local_exchange
+        exchange = @thread_local_exchange.get
+        if !exchange
+          exchange = declare_exchange!(local_channel, @exchange, @exchange_type, @durable)
+          @thread_local_exchange.set(exchange)
+        end
+        exchange
+      end
+
+      def local_channel
+        channel = @thread_local_channel.get
+        if !channel
+          channel = @hare_info.connection.create_channel
+          @thread_local_channel.set(channel)
+        end
+        channel
+      end
+
       def close
         close_connection
       end

logstash-output-rabbitmq.gemspec

@@ -1,6 +1,6 @@
 Gem::Specification.new do |s|
   s.name            = 'logstash-output-rabbitmq'
-  s.version         = '5.0.3'
+  s.version         = '5.1.0'
   s.licenses        = ['Apache License (2.0)']
   s.summary         = "Pushes events to a RabbitMQ exchange"
   s.description     = "This gem is a Logstash plugin required to be installed on top of the Logstash core pipeline using $LS_HOME/bin/logstash-plugin install gemname. This gem is not a stand-alone program"

spec/outputs/rabbitmq_spec.rb

@@ -163,6 +163,7 @@ def spawn_and_wait(instance)
     sleep 1
   end
   let(:message) { LogStash::Event.new("message" => "Foo Message", "extra_field" => "Blah") }
+  let(:encoded) { message.to_json }
   let(:test_connection) { MarchHare.connect(instance.send(:rabbitmq_settings)) }
   let(:test_channel) { test_connection.create_channel }
   let(:test_queue) {
@@ -196,7 +197,7 @@ def spawn_and_wait(instance)
     end
 
     it 'applies per message settings' do
-      instance.receive(message)
+      instance.multi_receive_encoded([[message, encoded]])
       sleep 1.0
 
       message, payload = test_queue.pop
@@ -213,7 +214,7 @@ def spawn_and_wait(instance)
         @received = payload
       end
 
-      instance.receive(message)
+      instance.multi_receive_encoded([[message, encoded]])
 
       until @received
         sleep 1