* VRFS-2530 - denormalize online for performance reasons

db/manifest

@@ -231,3 +231,4 @@ shopping_carts.sql
 recurly.sql
 add_track_resource_id.sql
 user_genres.sql
+user_online.sql

db/up/user_online.sql

@@ -0,0 +1,25 @@
+-- this was patched on the server without a proper migration, so the migration script here takes care to make sure it can run 2x
+ALTER TABLE users DROP COLUMN IF EXISTS online;
+DROP TRIGGER IF EXISTS connection_up_down ON connections;
+
+ALTER TABLE users ADD COLUMN online BOOL DEFAULT FALSE NOT NULL;
+
+CREATE OR REPLACE FUNCTION manage_user_online() RETURNS TRIGGER
+STRICT VOLATILE AS $$
+  BEGIN
+    IF (TG_OP = 'DELETE') THEN
+      UPDATE users set ONLINE = (SELECT COUNT(conn.id) FROM connections conn WHERE conn.user_id = OLD.user_id) > 0 WHERE users.id = OLD.user_id;
+      RETURN NULL;
+    ELSIF (TG_OP = 'INSERT') THEN
+      UPDATE users set ONLINE = (SELECT COUNT(conn.id) FROM connections conn WHERE conn.user_id = NEW.user_id) > 0 WHERE users.id = NEW.user_id;
+      RETURN NULL;
+    END IF;
+    RETURN NULL;
+  END;
+$$ LANGUAGE plpgsql;
+
+CREATE TRIGGER connection_up_down AFTER INSERT OR DELETE
+ON connections FOR EACH ROW EXECUTE PROCEDURE manage_user_online(user_id);
+
+-- ONE time bootstrap the new online field
+UPDATE users set online = (SELECT COUNT(conn.id) FROM connections conn WHERE conn.user_id = users.id) > 0;

ruby/lib/jam_ruby/models/notification.rb

@@ -267,7 +267,7 @@ module JamRuby
 
         notification_msg = format_msg(notification.description, {:user => user})
 
-        if friend.online
+        if friend.online?
           msg = @@message_factory.friend_request(
             friend.id,
             friend_request_id,

ruby/lib/jam_ruby/models/user.rb

@@ -253,7 +253,7 @@ module JamRuby
     end
 
     def online
-      @online ||= !self.connections.nil? && self.connections.size > 0
+      online?
     end
 
     def name

ruby/spec/jam_ruby/models/connection_spec.rb

@@ -103,4 +103,79 @@ describe JamRuby::Connection do
     end
   end
 
+  describe "triggers" do
+    describe "manage_user_online" do
+      it "offline for new user" do
+        user.online.should be_false
+      end
+
+      it "online/offline based on connection up/down" do
+        conn.touch # make a connection
+        user.reload
+        user.online.should be_true
+
+        conn.delete
+        user.reload
+        user.online.should be_false
+      end
+
+      it "verify that online up/down is only for affected user (no spillover)" do
+        user2 = FactoryGirl.create(:user)
+        user2.online.should be_false
+
+        conn.touch
+        user.reload
+        user2.reload
+
+        user.online.should be_true
+        user2.online.should be_false # make sure there is no spillover to unrelated users
+
+        conn2 = FactoryGirl.create(:connection,
+                           :user => user2,
+                           :music_session => music_session,
+                           :ip_address => "1.1.1.1",
+                           :client_id => "2")
+
+        user.reload
+        user2.reload
+
+        user.online.should be_true
+        user2.online.should be_true
+
+        # whack one of the connections
+        conn.delete
+        user.reload
+        user2.reload
+        user.online.should be_false
+        user2.online.should be_true
+
+        conn2.delete
+        user.reload
+        user2.reload
+        user.online.should be_false
+        user2.online.should be_false
+      end
+
+      it "n connections" do
+        conn.touch
+        conn2 = FactoryGirl.create(:connection,
+                                   :user => user,
+                                   :music_session => music_session,
+                                   :ip_address => "1.1.1.1",
+                                   :client_id => "2")
+
+        user.reload
+        user.online.should be_true
+
+        conn.delete
+        user.reload
+        user.online.should be_true
+
+        conn2.delete
+        user.reload
+        user.online.should be_false
+      end
+
+    end
+  end
 end

ruby/spec/jam_ruby/models/notification_spec.rb

@@ -779,6 +779,7 @@ describe Notification do
 
     it "success when online" do
       receiver_connection = FactoryGirl.create(:connection, user: @receiver)
+      @receiver.reload
       message = "Just a test message!"
       calls = count_publish_to_user_calls
       notification = Notification.send_text_message(message, @sender, @receiver)
@@ -796,6 +797,7 @@ describe Notification do
 
     it "success when online with long message" do
       receiver_connection = FactoryGirl.create(:connection, user: @receiver)
+      @receiver.reload
       message  = "0" * 203 # 200 is clip size
       calls = count_publish_to_user_calls
       notification = Notification.send_text_message(message, @sender, @receiver)