Add support for (off by default) autotruncation to avoid needing an e…

…xternal trigger. Not recommended.

config.yml

@@ -8,3 +8,4 @@ retentions:
   10:  360 #1 hour
   60:  10080  #1 week
   600: 52594 #1 year
+autotruncate: false

lib/batsd/receiver.rb

@@ -6,6 +6,7 @@ module Batsd
   #
   module Receiver
 
+
     # Exposes registered handlers 
     def self.handlers
       @handlers
@@ -47,6 +48,12 @@ def receive_data(msg)
     #
     class Daemon
 
+      # Force a truncation at all intervals at least every
+      # MAX_TRUNCATION_INTERVAL seconds. This prevents overflow issues in
+      # EventMachine, but is largely theoretical; it's unlikely any instance of
+      # the daemon would run this long.
+      MAX_TRUNCATION_INTERVAL = 2000000
+
       # Create a new daemon and set up it's options and 
       # register the handlers provided
       #
@@ -86,6 +93,17 @@ def run
             end
           end
 
+          if @options[:autotruncate]
+            puts "Enabling autotruncation"
+            @options[:retentions].each do |interval, n|
+              frequency = [interval.to_i * n.to_i, MAX_TRUNCATION_INTERVAL].min 
+              EventMachine.add_periodic_timer(frequency) do
+                Thread.new { Batsd::Truncator.new(@options).run(interval) }
+              end
+              puts "Truncator added for #{interval} second aggregations every #{frequency} seconds"
+            end
+          end
+
         end
       end