RailsMetrics is a new Rails engine which stores everything that is happening inside your application in the database, so you can profile each request, besides creating charts, statistics and extract useful information.

I’ve been working on it for the last couple months in parallel with ActiveSupport::Notifications, which is the foundation for RailsMetrics, and it was open sourced today by Engine Yard!

It was a challenging project due to its threaded nature and I will share a couple things I learned during the process in this blog later. For now, you can watch the screencast below to see what it does and how to install it:

As said in the video, getting it released is just the first step and now it’s your turn to fork and improve it by providing a better layout, creating new reports, charts, etc!

In case you are interested here are some screenshots that I tweeted earlier: http://twitpic.com/13e7fn/full and http://twitpic.com/13e7h2/full.

The javascript novell

A week ago I asked what people uses to create charts in Rails so I could evaluate what would be the best library to use in RailsMetrics. There were three types of libraries: server side ones, flash and javascript. Since I don’t want to depend on having neither RMagick nor Flash installed on the developer machine, I chose the javascript kind.

After some research I ended up with three libraries: g.raphael, flot and jqplot.

For RailsMetrics, I chose to use g.raphael since I can easily manipulate the objects it creates and it is the one which looks better (at least imho ). However it has poor documentation and the default charts have poor customization options compared to the other two libraries, so you end up tweaking the chart by hand (which was fine in my experience).

I’m waiting for your pull requests, enjoy!

Tags: charts, gems, javascript, metrics, notifications, rails
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This weekend during Rails Bugmash I stumbled across some nice posts about Rails 3 generators which motivated me to share them and add some comments!

First, David Trasbo wrote a nice guide about how to make your first Rails 3 generator, it covers up all the basic steps including setting it up in a gem. He also puts the deserved attention into Thor::Actions, which contains most helpers you need in a generator, like copy_file, template, create_file, empty_directory and so on.

On another post, Ben Scofield talks about apply method, which is also in Thor::Actions, and how to use it to dry your application templates.

Wait… so Thor::Actions is used both in generators and in Rails application templates? Exactly, Rails’ new generators unifies both application templates and generators API into one. While Thor::Actions holds basic methods, all Rails specific methods like environment, rakefile, generator are in Rails::Generators::Actions. If you already wrote an application template, you will feel more at home when writing a Rails 3 generator.

Paul Barry talks how easy it’s to customize your scaffold to use Rspec, Haml and Factory Girl instead of Test::Unit, Erb and Fixtures. This all works because scaffold is just a meta generator which provides hooks for template engine, test framework, ORM and so forth. A good way to see the hooks system working is by running script/generate scaffold --help before and after Paul changes, so you can see exactly how generators options update depending on the configuration values you set. While I wrote Rspec generators used in the example, he implemented himself Haml and Factory Girl generators and they can all be used as example if you plan to build your own.

Finally, Zigzag Chen wrote about templates customization and how you can change your scaffold controller to use json instead of the xml format. New generators have source paths, so you can customize them simply by copying files to RAILS_ROOT/lib/templates.

Rails Bugmash was excellent to gather feedback and we also got some tickets on Lighthouse, mainly about how generators help can be improved for people starting with Rails. Many thanks to Rails Bridge and besides the posts linked above, there is a generator guide, which may help you get started and maybe write your own post as well.

Tags: gems, generators, plugins, rails, ruby, thor
Posted in English | 8 Comments »