Add conn shutdown error log. Improve other error log messages

CHANGELOG

@@ -1,3 +1,6 @@
+* 4.2.0
+- Include URL of server when logging errors
+- Add warning log when connection is severed
 * 4.1.3
 - Bump march_hare version to 2.19.0 to fix reconnection failures with
   proxies. See

lib/logstash/plugin_mixins/rabbitmq_connection.rb

@@ -18,7 +18,7 @@ def self.included(base)
       end
 
       def setup_rabbitmq_connection_config
-        # RabbitMQ server address(es) 
+        # RabbitMQ server address(es)
         # host can either be a single host, or a list of hosts
         # i.e.
         #   host => "localhost"
@@ -201,16 +201,33 @@ def connect
 
         connection = MarchHare.connect(rabbitmq_settings)
 
-
-        connection.on_blocked { @logger.warn("RabbitMQ output blocked! Check your RabbitMQ instance!") }
-        connection.on_unblocked { @logger.warn("RabbitMQ output unblocked!") }
+        connection.on_shutdown do |conn, cause|
+           @logger.warn("RabbitMQ connection was closed!",
+                          :url => connection_url(conn),
+                          :automatic_recovery => @automatic_recovery,
+                          :cause => cause)
+        end
+        connection.on_blocked do
+          @logger.warn("RabbitMQ connection blocked! Check your RabbitMQ instance!",
+                       :url => connection_url(connection))
+        end
+        connection.on_unblocked do
+          @logger.warn("RabbitMQ connection unblocked!", :url => connection_url(connection))
+        end
 
         channel = connection.create_channel
         @logger.info("Connected to RabbitMQ at #{rabbitmq_settings[:host]}")
 
         HareInfo.new(connection, channel)
       end
 
+      # Mostly used for printing debug logs
+      def connection_url(connection)
+        user_pass = connection.user ? "#{connection.user}:XXXXXX@" : ""
+        protocol = params["ssl"] ? "amqps" : "amqp"
+        "#{protocol}://#{user_pass}#{connection.host}:#{connection.port}#{connection.vhost}"
+      end
+
       def sleep_for_retry
         Stud.stoppable_sleep(@connect_retry_interval) { @rabbitmq_connection_stopping }
       end

logstash-mixin-rabbitmq_connection.gemspec

@@ -1,7 +1,7 @@
 
 Gem::Specification.new do |s|
   s.name            = 'logstash-mixin-rabbitmq_connection'
-  s.version         = '4.1.3'
+  s.version         = '4.2.0'
   s.licenses        = ['Apache License (2.0)']
   s.summary         = "Common functionality for RabbitMQ plugins"
   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/plugin_mixins/rabbitmq_connection_spec.rb

@@ -96,6 +96,7 @@ def register
       allow(connection).to receive(:create_channel).and_return(channel)
       allow(connection).to receive(:on_blocked)
       allow(connection).to receive(:on_unblocked)
+      allow(connection).to receive(:on_shutdown)
 
       instance.register
     end