LoadError: no such file to load — flexmock

If you get this error, it means you need the statement: require 'rubygems' as the first line in your program.

Subversion 1.4.3 upgrade

Installed the latest version of Subversion. I had the older version 1.3, it looks like it installed successfully. svn --version shows the version as 1.4.3 and the files which were already in svn is still there.

Spam Prevention using the Obfuscator Widget for Mac OS

This plugin obfuscates your email so that spambots cannot recognize the email that you post on your web page.

Testing... my email is : bparanj@gmail.com

CSS Tweak - Nice Widget for Mac OS to optimize CSS

CSS Tweak! widget is very useful plugin to optimize your CSS files. Just select the file you want to optimize from the Finder, hit F12 and drop it into the widget, select the options and the rest is done by the widget! Very cool.

Code to HTML Mac OS widget test - Download Code2HTML

#!/bin/sh
pid=$ ( ps -o pid, command | grep '\<script/server\>' | awk ' { print $1 } ' )
kill -9 $pid
ruby script/server

Code2HTML is a nifty little plugin that helps to convert the code to html. It solved my problem of posting code to the blog without messing up the characters. It is very quick and easy to convert the code to html.

Colorizing Autotest

1. install turn and facets
2. require 'turn' in environment.rb in the Rails project.

Step 2 must be done for each project that needs the colorizing of the autotest window. Another way to do this is shown in one of the topfunky's videos.

The new :& syntax in Ruby

The advantage of the new syntax is that it allows passing in a proc object, which is powerful.

I am surprised how the presenter in the No Fluff Just Stuff thought its main purpose was to make the code concise!

Functional Testing in Rails that Requires Login

For RESTful authentication, there is a
login_as(user) method in AuthenticatedTestHelper module that sets the
current user
in the session from the user fixtures. This is under the lib directory.

In my functional test, I have:

def test_should_show_billing_profile_for_valid_login
login_as (:aaron)
get :show, :id => :aaron.id
assert_response :success
assert_select "html:root>head>title", "BillingProfiles: show"
end

users.yml looks like this:

quentin:
id: 1
login: quentin
email: quentin@example.com
salt: 7e3041ebc2fc05a40c60028e2c4901a81035d3cd
crypted_password: 00742970dc9e6319f8019fd54864d3ea740f04b1 # test
created_at: <%= 5.days.ago.to_s :db %>
aaron:
id: 2
login: aaron
email: aaron@example.com
salt: 7e3041ebc2fc05a40c60028e2c4901a81035d3cd
crypted_password: 00742970dc9e6319f8019fd54864d3ea740f04b1 # test
created_at: <%= 1.days.ago.to_s :db %>


class BillingProfilesController < ApplicationController

before_filter :login_required

def show
@user = User.find(session[:user], :include => [:billing_profile])
@billing_profile = @user.billing_profile

respond_to do |format|
format.html # show.rhtml
format.xml { render :xml => @billing_profile.to_xml }
end
end

The problem was that I was using session[:user_id] in my controller
whereas the RESTful authentication
module is using session[:user] as shown below:

module AuthenticatedTestHelper
# Sets the current user in the session from the user fixtures.
def login_as(user)
@request.session[:user] = user ? users(user).id : nil
end
....

So I changed my controller code to use session[:user] and my tests now
pass! The plugin itself has the API to help you do the functional
testing. Very nice indeed.

Installing Sqlite3 on Mac OS 10.4

1. Install DarwinPorts, download DarwinPorts 1.3.2-archive.tar.gz, unzip it.
2. Copy unzipped folder to some location
3. cd to that location cd darwinports/base and run ./configure
4. make
5. sudo make install
6. Add export PATH=$PATH:/opt/local/bin to ~/.profile
7. Either logout of Mac or do source .profile
8. Run port sync
9. sudo port install rb-sqlite3
10.Run sqlite databasename in a shell. You will go to the sqlite command prompt.

You can now create tables and run sql queries. The advantage of this database is that it speeds up the testing during development. It is very fast.

Rails Cheat Sheets

1. Assert Select CheatSheet
2. Ruby on Rails CheatSheet
3. Textmate Rails CheatSheet
4. Scriptaculous CheatSheet
5. RJS Demystified
6. Form Helpers CheatSheet
7. Active Record Relationships CheatSheet
8. AJAX CheatSheet
9. Ruby on Rails Testing CheatSheet
10. TextMate CheatSheet for Rails Developers

Email validation plugin

1.Setup the Rails project in Subversion by following the Subversion Primer for Rails blog post.
2. Ran into problems while installing plugins and after reading the James Adams's plugin book, I found the solution, I had to do:

script/plugin install –o https://svn.greenpeace.org/repositories/rails_plugins/validates_as_email/tags/0.1.4

to install the plugin.

I also looked at the test directory of the plugin and did the same assert in my unit test.

Restarting WEBrick using script

#!/bin/sh
pid=$(ps -o pid,command | grep '\' | awk '{print $1}')
kill -9 $pid
ruby script/server

This script restarts the Webrick cleanly (doing CTRL+c does not seem to shutdown the server)

Save it in a file, restart.sh. Do a chmod +x restart.sh and type the command: sh restart.sh to run it.

Rake Aborted! Migration Headache

If the migration is not working in AWDWR Rails examples. Remember that you must be on Edge Rails to make it work.

The Ruby Way, Ruby in a Nutshell and Rails Plugin Extending Rails Beyond the Core

The Ruby Way and Ruby in a Nutshell books arrived from Amazon today. I will post the review when I get a chance.

I also bought the "short cut" Rails Plugins by Addison Wesley, a 100 page pdf book. This book is a gem. More to come soon...

Ruby Interceptor

Beyond Java book had a good example of Interceptor in Ruby. It is like AOP, but is simpler.

1. Create an alias for the method that you want to intercept.
2. Define a new method with the same name as the old method
3. Delegate the call to the old method and add new code to do whatever you want in this method.

You basically open the class, intercept the calls to that method and add additional functionality to the method.

Head Rush AJAX

Very good book. Shows the big picture in a very easy to understand way. The concepts are well explained and brings any novice up to speed quickly. This book helped me to move on to study other materials like RJS Templates by OReilly.

Metaprogramming with Ruby

Ruby is a dynamic language. You can create classes and methods at runtime. This is metaprogramming. You can write code that writes code.

Example: Data format driving the code, CSV file with header at the top.

file: people.txt
----------------
name,age,weight,height
"Smith, John", 35, 175, "5'10"
"Ford, Anne", 49, 142, "5'4"
"Taylor, Burt", 55, 173, "5'10"
"Zubrin, Candace", 23, 133, "5'6"

Requirements:
1. The code must not change when a new attribute is added to the existing file or if we are given a different file with different attribute names.
2. The header values such as name and age must be treated as attribute names.

Create a class with a name derived from the file name. First line of the file must have list of attribute names. Checks that can added are: Check the attribute name is a legal Ruby method name, badly formed and missing data.

Given the file name we can create a class from its contents. So:

class_name = File.basename(file_name,".txt").capitalize # Create the class name
# e.g. "foo.txt" => "Foo"
klass = Object.const_set(class_name,Class.new)

Greasemonkey

Awesome Firefox extension, install the plugin and browse the scripts. I installed a script that blocks all Yahoo ads. No more annoying flashing ads in my email account. There are tons of useful scripts. One of the script I installed compares the price of Amazon books with other online stores.

Also, install the scripts one at a time. Install a script and use your browser for sometime and see if everything is fine. This is important because I installed lot of scripts on my laptop and now one of the script is opening up all the links in a new window!

If you install it one at a time, you can easily find out which script is causing the problem.

Metaprogramming - Write code that generates code

Uses

1. Open-Closed principle - Programs that need to pre-generate data tables
2. Mini-language to handle boilerplate code - Programs that have a lot of boilerplate code that cannot be abstracted into functions
3. Programs using techniques that are overly verbose in the language you are writing them in

The art of metaprogramming, Part 1: Introduction to metaprogramming - Jonathan Bartlett

Excellent article on Metaprogramming with Ruby

How to load fixtures after tables and indexes are created.

Steve Hammond's Blog had this interesting tip:

Can we tell a migration to load the fixtures after it has created the tables and indexes?

Fixtures.create_fixtures('test/fixtures', %w{archetypes tile_types tiles})

The first argument is the directory where the fixtures can be found and the second is an array of fixtures to be loaded. This will load the fixtures into the environment where the fixture is being run. As usual Rails will figure out YAML vs. csv fixtures for you