Notice that, inside the block, we have to call first method to retrieve the object. ActiveRecord tries hard to defer the actual database query as long as possible, but in this case we need to run the query to get the data from the server. If we didn't try to access the data, the object we'd be trying to save to the cache would be an instance of ActiveRecord::Relation . Luckily, objects of this type can't be marshaled, and the save to the cache will fail with an exception. …
- CRAZ8: Caching External Service API Calls
- Giles Bowkett: Rails Developers Should Take DCI Seriously
- A Fresh Cup: What's New in Edge Rails #35
- The Pug Automatic: Why mixed responsibilities resist refactoring
- paperplanes: Form Objects with ActiveModel
- Matthew Bass: Ruby Hoedown 2012 recap
Simple CRUD app with ActiveRecord, SQLite3 and YAML
Using Rack Middleware
You can read through the RubyLearning FAQ .
Some Fun Apps
Here are some of the fun apps created by the previous batch participants and deployed to Heroku:
Stock Exchange Quote Service .
Using Sinatra to access the Google+ API .
A Sorter Web Service in Sinatra
Finding Photos …
- giant robots smashing into other giant robots: Video: Sinatra at Boston.rb, part 2
- Ruby Inside: This Week in Ruby: Nominate Your Ruby Heroes, Include/Extend, Ruby on Netbeans, Jekyll-Bootstrap, and more
- Dead Programmer Society: LARubyConf 2009 - Blake Mizerany - "Sinatra: the Ultimate Rack Citizen"
- Rails Illustrated: Blazing Fast Speeds with Sinatra and Memcached
- Intridea - Company Blog: Intridea at Lonestar Ruby Conference
- Mark Tucker's Brainwork: Sending Email Using Gmail and Action Mailer
write a shell script or something to strip out ActiveRecord and swap
in DataMapper, so if you're doing this, and you do a lot of
consulting, you might start to accrue a little library of post-
installation scripts.
If this continues for a long time, and your company develops a
sufficiently sophisticated set of consistent deviations from Rails
canon, it's almost like you have an alternate version of Rails.
In my opinion the alternative "stack" is really …
- Giles Bowkett: A Simple Protocol For "You Are Not Your Code"
- Heroku: Rails Security Vulnerability
- Ruby on Rails Tutorial News: Rails security fixes, version upgrade
- New Relic: Making the Move to Rails 3
- Ruby Inside: The Past 2 Weeks in Ruby: 1.9.3-p286, JRuby 1.7RC2, Sidekiq Pro and Much More
- On the Path: Recap: Rails Girls Washington DC
…fragment if the object hasn't changed, and re-create the fragment if the object is different. For ActiveRecord objects, Rails builds this key automatically!
This technique requires a cache store like memcache that can automatically get rid of older items that are no-longer used, otherwise your cache will grow uncontrollably.
Here's an example from our blog software - the cache key will be something like "blogposts/{id}-{updated_at}"
- giant robots smashing into other giant robots: Better serialization, less as_json
- Kalzumeus Software: Ramit Sethi and Patrick McKenzie On Why Your Customers Would Be Happier If You Charged More
- Mike Perham: 12 Gems of Christmas #5 - lograge
- WyeWorks Blog - The Team's Voice: Rails 4 compilation links
- Phusion Corporate Blog: Why Rails 4 Live Streaming is a big deal
- Ruby Inside: A Mega Ruby News and Release Roundup for July 2012 in 97 Links
If you use ActiveRecord and have a bunch of settings in your database.yml file, you are making use of dependency injection. You are influencing a composition through arguments passed into the connection manager. You probably use this all over your own code, too—whenever you defer the creation of an object and allow that object to be overridden by something passed in via arguments. These are all cases of DI.
In other words: DI is not magical. Don't hate it.
But...
If you're …
- Global Nerdy: Ignite Your Coding: This Afternoon with Glenn Block!
- CaelumObject Developers' Blog: REST and Web development: new VRaptor and Restfulie releases
- DevInterface Blog: Ruby Enumerables: Hashes
- A Fresh Cup: One- and Two-Letter Gems
- carpeaqua by Justin Williams: Think First, Code Later
- giant robots smashing into other giant robots: Movin' and Shakin'
ActiveRecord protects you against SQL injection by escaping input for you. For example the following works as expected, with no vulnerability: User.find_by_name("kotori'; DROP TABLE USERS; --") # => SELECT * FROM users WHERE name = 'kotori\'; DROP TABLE USERS; --' LIMIT 1
But ActiveRecord also defines ways for the programmer to inject SQL fragments into the query so that the programmer can customize the query when necessary. The injection interfaces are …
- Ruby-coloured glasses: Making views/triggers/functions work in mysql for rails
- David Chelimsky: rspec-2.12 is released
- Ruby Inside: A Mega Ruby News and Release Roundup for July 2012 in 97 Links
- Giles Bowkett: Rails, Ruby, And Type-Checking
- New Relic: Rails Machine Adds APM from New Relic to its App Management Platform for Rails
- Ruby on Rails, London - The Blog by Dynamic50: Ruby on Rails Training Courses
A SQL injection vulnerability has been found in ActiveRecord that impacts all versions of Rails:
I have released Hobo 1.3.3 that patches Hobo's vulnerability to this issue.
if you are using Hobo 2.0 it is recommended that you upgrade to Rails 3.2.10, although I have also pushed the security patch to github master.
The Hobo fix only impacts Hobo's usage. If you use find_by_ in your own code, you must fix those up yourself by coercing the …
- ActiveScaffold - Blog: ActiveScaffold @ RailsConf
- Rails Inside: Hobo 1.0 - A Rapid Rails Web App Builder - Released
…in some thread-safe data structures like queues and condition variables. Requiring ActiveRecord brings in a world of dependencies and causes a number of behavioral changes to Ruby that some consider impolite.
In some tinkerings with Clojure this weekend, I was struck how the ns function is more effective at both declaring dependency and coupling and in restricting the possible distress those qualities may bring. Consider this snippet from my weekend project: (ns hrq.routes (:use compojure.core …
- RubyLearning Blog: Clojure 101 Course - 2nd batch
- Heroku: Clojure on Heroku
- Trevor Turk: Links for 07-08-11
- Lovable Lyle: HuntFunc Meeting: December 7
- Synthesis: Happy 4th
- paperplanes: June Reading List
Oh, and the fraud checking is no longer in a subclass of ActiveRecord::Base , so it's easier to test without Rails if that's what you're into.
Using a module
You could also use a module for this:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 class Receipt < ActiveRecord :: Base include FraudCheckable end module Receipt::FraudCheckable def fraudulent? check_this check_that end private def check_this # ... end def check_that # ... end end
This has many of the same …
- Signal vs. Noise: Pattern vision
- Global Nerdy: CUSEC 2010 Keynote: Reg Braithwaite - "Beautiful Failure"
- Ruby Inside: This Week in Ruby: MRI 1.9.3-p327, Rails 3.2.9, Capybara 2.0, and the Fukuoka Ruby Award
- Transcending Frontiers: The Frontier Group - Busy Times Ahead
- James on Software: Crazy, Heretical, and Awesome: The Way I Write Rails Apps
- gnuu.org: Let's Do Some Engineering Pt. 1: Design Patterns
…Netzke lets you do much more than just quickly create a grid that seamlessly works with an ActiveRecord model without using any code generators. In fact, Netzke is best suited for making complex one-page web applications that make use of hundreds of data models and implement sophisticated workflows. One of the many techniques that Netzke as a modular GUI framework provides to you, is component nesting. Here I'll show you how easy it is to nest 3 differently configured instances …
- Rails Inside: Netzke: Rich Internet Apps with Ext JS and Rails
- Mental Paging Space: New widgets for rails 3