Addition of a resend_attempts counter to prevent output worker blocking.

CHANGELOG.md

@@ -1,3 +1,6 @@
+## 2.1.0
+ - Preventing output blocking when the graphite server is down by introducing a resend_attempts counter.
+
 ## 2.0.3
  - Fixed empty/nil messages handling
 
@@ -10,4 +13,4 @@
  - Added support for sprintf in field formatting
 
 ## 1.0.1
- - Added support for nested hashes as values
+ - Added support for nested hashes as values

lib/logstash/outputs/graphite.rb

@@ -26,6 +26,9 @@ class LogStash::Outputs::Graphite < LogStash::Outputs::Base
   # Interval between reconnect attempts to Carbon.
   config :reconnect_interval, :validate => :number, :default => 2
 
+  # Number of attempts to be made resending metrics before abandoning
+  config :resend_attempts, :validate => :number, :default => 3
+
   # Should metrics be resent on failure?
   config :resend_on_failure, :validate => :boolean, :default => false
 
@@ -94,12 +97,14 @@ def register
 
   def connect
     # TODO(sissel): Test error cases. Catch exceptions. Find fortune and glory. Retire to yak farm.
+    numattempts = 0
     begin
+      numattempts += 1
       @socket = TCPSocket.new(@host, @port)
     rescue Errno::ECONNREFUSED => e
       @logger.warn("Connection refused to graphite server, sleeping...", :host => @host, :port => @port)
       sleep(@reconnect_interval)
-      retry
+      retry if numattempts < @resend_attempts
     end
   end
 
@@ -130,13 +135,15 @@ def receive(event)
 
       # Catch exceptions like ECONNRESET and friends, reconnect on failure.
       # TODO(sissel): Test error cases. Catch exceptions. Find fortune and glory.
+      numattempts = 0
       begin
+        numattempts += 1
         @socket.puts(message)
       rescue Errno::EPIPE, Errno::ECONNRESET, IOError => e
         @logger.warn("Connection to graphite server died", :exception => e, :host => @host, :port => @port)
         sleep(@reconnect_interval)
         connect
-        retry if @resend_on_failure
+        retry if @resend_on_failure || numattempts < @resend_attempts
       end
     end
   end

logstash-output-graphite.gemspec

@@ -1,7 +1,7 @@
 Gem::Specification.new do |s|
 
   s.name            = 'logstash-output-graphite'
-  s.version         = '2.0.3'
+  s.version         = '2.1.0'
   s.licenses        = ['Apache License (2.0)']
   s.summary         = "This output allows you to pull metrics from your logs and ship them to Graphite"
   s.description     = "This gem is a logstash plugin required to be installed on top of the Logstash core pipeline using $LS_HOME/bin/plugin install gemname. This gem is not a stand-alone program"