somebox

Thoughts about Rails Presenters

This is a collection of links, examples and rants about Presenters/Decorators in Rails.

---

The "Decorator" pattern slowly started gaining popularity in Rails several years ago. It is not part of core Rails, and there's many different interpretations about how it should work in practice.

Jay Fields wrote about it in 2007 (before he switched back to Java and then Clojure): http://blog.jayfields.com/2007/03/rails-presenter-pattern.html

somebox

#!/usr/bin/env ruby
require 'rubygems'
require 'raindrops'
require 'statsd'

#
#  This script monitors the active and queued unicorn processes.
#  It uses the raindrops gem to look at the unix domain socket.
#  Stats are polled every second (for one minute) and pushed to
#  statsd as a counter. This script runs once a minute.

somebox

#!/usr/bin/env ruby
require 'socket'

# This script runs every minute, captures stats about redis
# and forwards them to graphite as counter values.

# Graphite/carbon settings
GRAPHITE_HOST="graphite.intra.local.ch"
GRAPHITE_PORT=8125

somebox

>> h={a:true,b:false,c:1}
=> {:a=>true, :b=>false, :c=>1}
>> h[:a].present?
=> true
>> h[:a].presence
=> true
>> h[:b].present?
=> false
>> h[:b].presence
=> nil

somebox

diff --git a/Gemfile b/Gemfile
index 34fced8..7edff29 100644
--- a/Gemfile
+++ b/Gemfile
@@ -16,6 +16,8 @@ group :development do
   gem "bundler", 	">= 1.0.0"
   gem "jeweler", 	">= 1.8.3"
   gem "simplecov",">= 0.5"
+  gem "fastercsv"
+  gem "i18n"

somebox

    rescue_from ActionController::RoutingError do |exception|
      render :file => Rails.root.join('public', '404.html'), :status => "404", :layout=>false
    end

somebox

# The following recipe works with upstream rails proxy for custom 404s and 500s.
# Errors are usually handled via rails except if proxy is really down, in which case
# nginx needs a bit more configration.

server {
  # ...
  
  location / {
    error_page 404 = @rails; # let rails show a page with suggestions
    try_files maintenance.html @rails;

somebox

APP_ROOT = File.expand_path(File.dirname(File.dirname(__FILE__)))

if ENV['MY_RUBY_HOME'] && ENV['MY_RUBY_HOME'].include?('rvm')
  begin
    rvm_path = File.dirname(File.dirname(ENV['MY_RUBY_HOME']))
    rvm_lib_path = File.join(rvm_path, 'lib')
    $LOAD_PATH.unshift rvm_lib_path
    require 'rvm'
    RVM.use_from_path! APP_ROOT
  rescue LoadError

somebox

# A More Awesome PS1
# - only show username if its not the usual one
# - only show hostname if its not my local box (checks SSH_CONNECTION)
# - show root username in red
# - show current path, and smart truncate longer ones (>35 chars)
# - show git branch in brackets
# - show a red star for uncommitted git changes
# - show local hostname in green (192.*,10.*,::1) 
# - show other hostnames in white

somebox

require 'builder'
require 'digest/md5'

class Content < ActiveRecord::Base
  belongs_to :user
end

class Section < ActiveRecord::Base
  has_many :assigned_sections
  has_many :articles, :order => 'position', :through => :assigned_sections