early implementation of "best" counters

lib/von.rb

@@ -3,6 +3,7 @@
 
 require 'von/config'
 require 'von/counter'
+require 'von/best_counter'
 require 'von/period'
 require 'von/version'
 

lib/von/best_counter.rb

@@ -0,0 +1,43 @@
+module Von
+  class BestCounter
+
+    def initialize(parent)
+      @parent  = parent
+      @field   = parent.field
+      @periods = Von.config.bests[@field]
+    end
+
+    # Returns the Redis hash key used for storing counts for this Counter
+    def hash_key
+      @hash_key ||= "#{Von.config.namespace}:counters:bests:#{@field}"
+    end
+
+    def increment
+      return if @periods.nil?
+
+      @periods.each do |period|
+        # TODO: subclass counter (or somethin) and add hincrby/etc helpers
+
+        current_timestamp = Von.connection.hget("#{hash_key}:#{period}:current", 'timestamp')
+
+        # TODO: this logic "seems" backwards, rethink current_timestamp
+        if period.timestamp != current_timestamp
+          # changing current period
+          current_total  = Von.connection.hget("#{hash_key}:#{period}:current", 'total').to_i
+          best_total     = Von.connection.hget("#{hash_key}:#{period}:best", 'total').to_i
+
+          Von.connection.hset("#{hash_key}:#{period}:current", 'total', 1)
+          Von.connection.hset("#{hash_key}:#{period}:current", 'timestamp', period.timestamp)
+
+          if best_total < current_total
+            Von.connection.hset("#{hash_key}:#{period}:best", 'total', current_total)
+            Von.connection.hset("#{hash_key}:#{period}:best", 'timestamp', current_timestamp)
+          end
+        else
+          Von.connection.hincrby("#{hash_key}:#{period}:current", 'total', 1)
+        end
+      end
+    end
+
+  end
+end

lib/von/counter.rb

@@ -23,6 +23,8 @@ def hash_key
     def increment
       total = Von.connection.hincrby(hash_key, 'total', 1)
 
+      BestCounter.new(self).increment
+
       increment_periods
 
       total

lib/von/period.rb

@@ -9,7 +9,9 @@ class Period
       :monthly  => :month,
       :yearly   => :year
     }
-
+    TIME_PERIODS = TIME_UNITS.invert
+
+    attr_reader :period
     attr_reader :counter_key
     attr_reader :length
     attr_reader :format
@@ -19,12 +21,16 @@ class Period
     # counter - the field name for the counter
     # period - the time period one of AVAILABLE_PERIODS
     # length - length of period
-    def initialize(counter_key, period, length)
+    def initialize(counter_key, period, length = nil)
       @counter_key = counter_key
       @period      = period.to_sym
       @length      = length
       @format      = Von.config.send(:"#{@period}_format")
     end
+
+    def to_s
+      @period.to_s
+    end
 
     # Returns a Symbol representing the time unit
     # for the current period.
@@ -37,6 +43,15 @@ def hours?
       @period == :hourly
     end
 
+    def now
+      # TODO: this may break minutes
+      DateTime.now.beginning_of_hour
+    end
+
+    def prev
+      hours? ? now.ago(3600) : now.send(:"prev_#{_period.time_unit}")
+    end
+
     # Returns the Redis hash key used for storing counts for this Period
     def hash_key
       @hash ||= "#{Von.config.namespace}:counters:#{@counter_key}:#{@period}"
@@ -48,9 +63,11 @@ def list_key
     end
 
     # Returns the Redis field representation used for storing the count value
+    # TODO: rename this
     def field
       Time.now.strftime(format)
     end
+    alias :timestamp :field
 
     def self.exists?(period)
       AVAILABLE_PERIODS.include?(period)

test/best_counter_test.rb

@@ -0,0 +1,31 @@
+require 'test_helper'
+
+describe Von::BestCounter do
+  Counter = Von::BestCounter
+
+  before :each do
+    Timecop.freeze(Time.local(2013, 01, 01))
+    Von.config.init!
+    @redis = Redis.new
+    @redis.flushall
+  end
+
+  it "increments the best counter for a period" do
+    Von.configure do |config|
+      config.counter 'foo', :best => :day
+    end
+
+    Counter.increment('foo')
+
+    Timecop.freeze(Time.local(2013, 01, 02))
+    10.times { Counter.increment('foo') }
+    Timecop.freeze(Time.local(2013, 01, 03))
+    3.times { Counter.increment('foo') }
+
+    @redis.hget('von:counters:bests:foo:daily:current', 'timestamp').must_equal '2013-01-03'
+    @redis.hget('von:counters:bests:foo:daily:current', 'total').must_equal '3'
+    @redis.hget('von:counters:bests:foo:daily:best', 'timestamp').must_equal '2013-01-02'
+    @redis.hget('von:counters:bests:foo:daily:best', 'total').must_equal '10'
+  end
+
+end