#378 FnordMetric

Sep 04, 2012 | 10 minutes | Tools

FnordMetric allows you to chart events in real time. This is great for keeping track of user activity in your Rails app as demonstrated in this episode.

Click to Play Video ▶

Download:
mp4 Full Size H.264 Video (25.5 MB)
m4v Smaller H.264 Video (12.9 MB)
webm Full Size VP8 Video (14.3 MB)
ogv Full Size Theora Video (28.8 MB)

Resources

FnordMetric

terminal

brew install redis
redis-server /usr/local/etc/redis.conf
gem install fnordmetric
ruby full_example.rb

fnordmetric_app.rb

require "fnordmetric"
FnordMetric.namespace :store do
 hide_active_users
 
 toplist_gauge :popular_products, title: "Popular Products"
 distribution_gauge :popular_prices, title: "Popular Prices",
 value_ranges: [0..5, 5..10, 10..20, 20..50, 50..10000]
 gauge :product_views_per_second, tick: 1.second
 widget "Product Views",
 title: "Views per Second",
 type: :timeline,
 width: 100,
 gauges: :product_views_per_second,
 include_current: true,
 autoupdate: 1
 
 event :view_product do
 observe :popular_products, data[:name]
 observe :popular_prices, data[:price]
 incr :product_views_per_second
 end
end
FnordMetric::Web.new(port: 4242)
FnordMetric::Worker.new
FnordMetric.run

config/intializers/fnordmetric.rb

FNORD_METRIC = FnordMetric::API.new

models/product.rb

def trigger_view_event
 FNORD_METRIC.event(attributes.merge(_type: :view_product))
end

lib/tasks/product.rake

namespace :fnordmetric do
 desc "Populate FnordMetric with events to simulate user activity"
 task :populate => :environment do
 products = Product.all
 loop do
 products.sample.trigger_view_event
 sleep(rand)
 end
 end
end