implement traffic counter that adjusts redness of lobsters logo

app/assets/stylesheets/application.css

@@ -239,12 +239,6 @@ div#inside {
 	margin-left: 4px;
 	margin-right: 11px;
 }
-#l_holder.dead {
-	background-color: black;
-}
-#l_holder.boring {
-	background-color: darkred;
-}
 
 #header h1 {
 	font-size: 11pt;

app/controllers/application_controller.rb

@@ -1,6 +1,9 @@
 class ApplicationController < ActionController::Base
   protect_from_forgery
   before_filter :authenticate_user
+  before_filter :increase_traffic_counter
+
+  TRAFFIC_DECREMENTER = 0.1
 
   def authenticate_user
     if session[:u]
@@ -10,6 +13,23 @@ class ApplicationController < ActionController::Base
     true
   end
 
+  def increase_traffic_counter
+    @traffic = 1.0
+
+    Keystore.transaction do
+      date = (Keystore.value_for("traffic:date") || Time.now.to_i)
+      traffic = (Keystore.incremented_value_for("traffic:hits", 0).
+        to_f / 100.0) + 1.0
+
+      # every second, decrement traffic by some amount
+      @traffic = [ 1.0, traffic.to_f -
+        ((Time.now.to_i - date) * TRAFFIC_DECREMENTER) ].max
+
+      Keystore.put("traffic:date", Time.now.to_i)
+      Keystore.put("traffic:hits", (@traffic * 100.0).to_i)
+    end
+  end
+
   def require_logged_in_user
     if @user
       true

app/views/global/_header.html.erb

@@ -1,6 +1,7 @@
 <div id="header">
   <div id="headerleft">
-    <a id="l_holder" class="boring" href="/"></a>
+    <a id="l_holder" style="background-color: #<%= sprintf("%02x%02x%02x",
+    [ 255, (@traffic * 5).floor + 50.0 ].min, 0, 0) %>;" href="/"></a>
 
     <% links = { "/" => "Home", "/newest" => "Newest Stories" } %>
     <% if @user %>

db/migrate/20120816203248_keystore_bigint.rb

@@ -0,0 +1,8 @@
+class KeystoreBigint < ActiveRecord::Migration
+  def up
+    execute("ALTER TABLE keystores CHANGE value value BIGINT")
+  end
+
+  def down
+  end
+end

db/schema.rb

@@ -11,7 +11,7 @@
 #
 # It's strongly recommended to check this file into your version control system.
 
-ActiveRecord::Schema.define(:version => 20120712174445) do
+ActiveRecord::Schema.define(:version => 20120816203248) do
 
   create_table "comments", :force => true do |t|
     t.datetime "created_at",                                                                          :null => false
@@ -46,7 +46,7 @@ ActiveRecord::Schema.define(:version => 20120712174445) do
 
   create_table "keystores", :id => false, :force => true do |t|
     t.string  "key",   :limit => 50, :default => "", :null => false
-    t.integer "value",                               :null => false
+    t.integer "value", :limit => 8
   end
 
   add_index "keystores", ["key"], :name => "key", :unique => true