Fixing logic a bit

README.markdown

@@ -13,11 +13,11 @@ sudo gem install periodic_template
 Create columns
 --------------
 
-For every counter column (X), you should also have a <code>X\_computed\_at</code> datetime column.
+Define period columns using this format: <code>X\_last\_1\_week</code> or <code>X\_last\_6\_hours</code>.
 
-To define period columns, use this format: <code>X\_last\_1\_week</code> or <code>X\_last\_6\_hours</code>. The name should follow the format of [ActiveSupport's time extensions](http://api.rubyonrails.org/classes/ActiveSupport/CoreExtensions/Numeric/Time.html).
+The name should follow the format of [ActiveSupport's time extensions](http://api.rubyonrails.org/classes/ActiveSupport/CoreExtensions/Numeric/Time.html).
 
-If you are adding this to a counter that already has a count, you will also need a <code>X\_starting\_value</code> integer column.
+Also add a <code>counter_data</code> varchar column with a length of 2048.
 
 Create configuration
 --------------------

lib/periodic_counter.rb

@@ -26,40 +26,40 @@ def initialize(environment, root)
       if columns
         columns.each do |column|
           if counters.include?(column)
+            # Find period columns
             period = columns.select do |col|
               col =~ /^#{column}/ &&
               col != column &&
-              !col.include?('computed_at') &&
-              !col.include?('starting_value')
+              !col.include?('_data')
             end
-            select_columns = [ 'id', column, "#{column}_computed_at", "#{column}_starting_value" ] + period
-            select_columns &= columns
+            # Grab all records
+            select_columns = [ 'id', column, "#{column}_data" ]
+            select_columns += period
             records = ActiveRecord::Base.connection.select_all <<-SQL
               SELECT #{select_columns.join(', ')}
               FROM #{table}
             SQL
             records.each do |record|
               id = record.delete('id')
-              computed_at = ActiveRecord::ConnectionAdapters::Column.string_to_time(
-                record.delete("#{column}_computed_at")
-              )
+              data = YAML::load(record["#{column}_data"] || '') || {}
+              computed_at = data['computed_at'] || Time.now.utc
               count = record.delete(column).to_i
-              time_since_compute = Time.now.utc - computed_at.utc
-              if record.keys.include?("#{column}_starting_value")
-                unless record["#{column}_starting_value"]
-                  record["#{column}_starting_value"] = count
-                end
-                starting_value = record["#{column}_starting_value"].to_i
-              end
-              starting_value ||= 0
+              time_since_compute = Time.now.utc - computed_at
+              # Set period counters
               period.each do |col|
-                period_count = record[col].to_i
                 duration = column_to_period_integer(col)
+                starting_value = data[col].to_i
                 if (time_since_compute - duration) >= 0
-                  record[col] = count - period_count - starting_value
+                  record[col] = count - starting_value
+                  data[col] = count
+                else
+                  data[col] ||= count
                 end
               end
-              set = record.collect { |col, value| "#{col} = #{value}" }
+              # Update record
+              data['computed_at'] = Time.now.utc
+              record["#{column}_data"] = "'#{YAML::dump(data)}'"
+              set = record.collect { |col, value| "#{col} = #{value || 0}" }
               ActiveRecord::Base.connection.update <<-SQL
                 UPDATE #{table}
                 SET #{set.join(', ')}

spec/db/migrate/001_counters_without_starting_value.rb → spec/db/migrate/001_counters.rb

@@ -1,12 +1,10 @@
-class CountersWithoutStartingValue < ActiveRecord::Migration
+class Counters < ActiveRecord::Migration
   def self.up
     create_table :counters do |t|
       t.integer :counter
-      t.datetime :counter_computed_at
       t.integer :counter_last_day
       t.integer :counter_last_2_days
-      t.integer :counter_last_week
-      t.integer :counter_last_2_weeks
+      t.string :counter_data, :limit => 2048
     end
   end
 

spec/periodic_counter_spec.rb

@@ -1,98 +1,66 @@
 require 'spec_helper'
 
 describe PeriodicCounter do
-  describe "without starting value" do
-
-    before(:each) do
-      $db.migrate(1)
-      $db.migrate(0)
-      $db.migrate(1)
-      create_counter
-    end
-
-    it "should add to counter_last_day" do
-      stub_time(Time.now + 1.day)
-      start
-      Counter.last.counter_last_day.should == 2
-      Counter.last.counter_last_2_days.should == 1
-      Counter.last.counter_last_week.should == 1
-      Counter.last.counter_last_2_weeks.should == 1
-    end
-
-    it "should add to counter_last_2_days" do
-      stub_time(Time.now + 2.days)
-      start
-      Counter.last.counter_last_day.should == 2
-      Counter.last.counter_last_2_days.should == 2
-      Counter.last.counter_last_week.should == 1
-      Counter.last.counter_last_2_weeks.should == 1
-    end
-
-    it "should add to counter_last_week" do
-      stub_time(Time.now + 1.week)
-      start
-      Counter.last.counter_last_day.should == 2
-      Counter.last.counter_last_2_days.should == 2
-      Counter.last.counter_last_week.should == 2
-      Counter.last.counter_last_2_weeks.should == 1
-    end
-
-    it "should add to counter_last_2_weeks" do
-      stub_time(Time.now + 2.weeks)
-      start
-      Counter.last.counter_last_day.should == 2
-      Counter.last.counter_last_2_days.should == 2
-      Counter.last.counter_last_week.should == 2
-      Counter.last.counter_last_2_weeks.should == 2
-    end
+
+  before(:all) do
+    $db.migrate(1)
+    $db.migrate(0)
+    $db.migrate(1)
+    create_counter
+  end
+
+  it "should not do anything but set up data" do
+    start
+    attributes = Counter.last.attributes
+    data = attributes.delete('counter_data')
+    data.delete('computed_at').to_s.should == Time.now.utc.to_s
+    data.should == {
+      "counter_last_day"=>1,
+      "counter_last_2_days"=>1
+    }
+    attributes.should == {
+      "id"=>1,
+      "counter"=>1,
+      "counter_last_day"=>0,
+      "counter_last_2_days"=>0
+    }
+  end
+
+  it "should add to counter_last_day" do
+    Counter.last.update_attribute :counter, 2
+    stub_time(Time.now + 1.day)
+    start
+    attributes = Counter.last.attributes
+    data = attributes.delete('counter_data')
+    data.delete('computed_at').to_s.should == Time.now.utc.to_s
+    data.should == {
+      "counter_last_day"=>2,
+      "counter_last_2_days"=>1
+    }
+    attributes.should == {
+      "id"=>1,
+      "counter"=>2,
+      "counter_last_day"=>1,
+      "counter_last_2_days"=>0
+    }
   end
 
-  describe "with starting value" do
-
-    before(:each) do
-      $db.migrate(2)
-      $db.migrate(0)
-      $db.migrate(2)
-      Counter.reset_column_information
-      create_counter
-      start
-      Counter.last.update_attribute :counter, 6
-    end
-
-    it "should add to counter_last_day" do
-      stub_time(Time.now + 1.day)
-      start
-      Counter.last.counter_last_day.should == 2
-      Counter.last.counter_last_2_days.should == 1
-      Counter.last.counter_last_week.should == 1
-      Counter.last.counter_last_2_weeks.should == 1
-    end
-
-    it "should add to counter_last_2_days" do
-      stub_time(Time.now + 2.days)
-      start
-      Counter.last.counter_last_day.should == 2
-      Counter.last.counter_last_2_days.should == 2
-      Counter.last.counter_last_week.should == 1
-      Counter.last.counter_last_2_weeks.should == 1
-    end
-
-    it "should add to counter_last_week" do
-      stub_time(Time.now + 1.week)
-      start
-      Counter.last.counter_last_day.should == 2
-      Counter.last.counter_last_2_days.should == 2
-      Counter.last.counter_last_week.should == 2
-      Counter.last.counter_last_2_weeks.should == 1
-    end
-
-    it "should add to counter_last_2_weeks" do
-      stub_time(Time.now + 2.weeks)
-      start
-      Counter.last.counter_last_day.should == 2
-      Counter.last.counter_last_2_days.should == 2
-      Counter.last.counter_last_week.should == 2
-      Counter.last.counter_last_2_weeks.should == 2
-    end
+  it "should add to counter_last_2_days" do
+    Counter.last.update_attribute :counter, 3
+    stub_time(Time.now + 3.days)
+    start
+    attributes = Counter.last.attributes
+    data = attributes.delete('counter_data')
+    data.delete('computed_at').to_s.should == Time.now.utc.to_s
+    data.should == {
+      "counter_last_day"=>3,
+      "counter_last_2_days"=>3
+    }
+    attributes.should == {
+      "id"=>1,
+      "counter"=>3,
+      "counter_last_day"=>1,
+      "counter_last_2_days"=>2
+    }
   end
 end

spec/spec_helper.rb

@@ -11,14 +11,7 @@
 $db.establish_connection
 
 def create_counter
-  Counter.create(
-    :counter => 3,
-    :counter_computed_at => Time.now,
-    :counter_last_day => 1,
-    :counter_last_2_days => 1,
-    :counter_last_week => 1,
-    :counter_last_2_weeks => 1
-  )
+  Counter.create(:counter => 1)
 end
 
 def start
@@ -30,4 +23,5 @@ def stub_time(time)
 end
 
 class Counter < ActiveRecord::Base
+  serialize :counter_data
 end