DZone Snippets: Leethal's Code Snippets

Array to HTL list helper

leethal (August Lilleaas) — Sat, 17 Nov 2007 05:37:13 GMT

Makes a HTML list out of any array. The objects in the array is yielded to the block. Usage:


<%= list(@posts) { |post| link_to post.title, posts_url(post) } %>

And the actual helper (put it in application_helper.rb):



def list(stuff, &block)

  content_tag(:ul, stuff.map { |thingie| content_tag(:li, yield(thingie)) })

end

Freeze rails to older version

leethal (August Lilleaas) — Fri, 02 Nov 2007 09:47:20 GMT

This is an explanation of how to make a new, fresh Rails app of any released version of Rails.

First, generate a new rails app:

rails my_project

cd my_project

Find the release you want to use from this list. There's a bunch of stuff in there - the Rails releases are prefixed with rel_.

Then, ender this command to freeze Rails to the version you want. Remember to change the TAG= part (doh).

rake rails:freeze:edge TAG=rel_1-0-0

When this finishes, run the 'rails' command of the rails version you just froze to to have the rails app itself (the stuff in environment/ and so on) turned into the correct version.

ruby vendor/rails/railties/bin/rails .

Woot!

RSpec extension: testing attr_protected and attr_accessible

leethal (August Lilleaas) — Mon, 29 Oct 2007 20:28:23 GMT

Include this module in a spec or inside the Spec::Runner.configure block in the spec_helper.rb. Because i suck, should_not is not working as expected. Usage:



class User < ActiveRecord::Base

  # either 

  attr_accessible :username, :full_name

  # or

  attr_protected :admin, :foo

end



# ...



it "should protect admin and foo" do

  @user.should protect_attributes(:admin, :foo)

end

Here goes:



module CustomExpectations

  class ProtectAttributes

    def initialize(*attributes)

      @attributes = attributes

    end

    

    def matches?(target)

      @target = target

      

      calculate_protected_methods

      perform_check

    end

    

    def failure_message

      "expected #{@failed_attribute} to be protected"

    end

    

    def negative_failure_message

      "expected #{@failed_attribute} to not be protected"

    end

    

    private

    

    def calculate_protected_methods

      read = proc {|var| @target.instance_eval { self.class.read_inheritable_attribute(var) } }

      accessible = read.call("attr_accessible")

      protekted = read.call("attr_protected")

      all = @target.class.column_names.map(&:to_sym)

      

      @protected = []

      @protected << protekted if protekted

      @protected << (all - accessible) if accessible

      @protected.flatten!

      

      @accessible = all - @protected

    end

    

    def perform_check

      failed_attributes = (@attributes & @accessible)

      @failed_attribute = failed_attributes.first

      failed_attributes.empty?

    end

  end

  

  def protect_attributes(attributes)

    ProtectAttributes.new(attributes)

  end

  

  def protect_attribute(attribute)

    ProtectAttributes.new(*[attribute])

  end

end

Downgrading a new rails app

leethal (August Lilleaas) — Mon, 22 Oct 2007 13:29:41 GMT

Use this code to downgrade to version X of rails. Use the tags found in the repository.


rails my_project

cd my_project



rake rails:freeze:edge TAG=rel_1-1-0

ruby vendor/rails/railties/bin/rails .

Simple user model with password crypting

leethal (August Lilleaas) — Fri, 19 Oct 2007 12:50:41 GMT

A simple user model. It's using the virtual password attribute 'password' to store the clear-text password. This is what e.g. forms use for password input. It stores this password in the password_hash column.

It allows for user editing, using the same form as user creation. The password won't be updated, and validations will pass, if the user doesn't touch the password field in the form.



require "digesh/sha1"

class User < ActiveRecord::Base

  validates_confirmation_of :password, :if => :perform_password_validation?

  validates_presence_of :password, :if => :perform_password_validation?



  before_save :hash_password

  attr_accessor :password



  # Returns true if the password passed matches the password in the DB

  def valid_password?(password)

    self.password_hash == self.class.hash_password(password)

  end



  private



  # Performs the actual password encryption. You want to change this salt to something else.

  def self.hash_password(password, salt = "meeQue8Zucijoo7")

    Dihest::SHA1.hexdigest(password, salt)

  end



  # Sets the hashed version of self.password to password_hash, unless it's blank.

  def hash_password

    self.password_hash = self.class.hash_password(self.password) unless self.password.blank?

  end

 

  # Assert wether or not the password validations should be performed. Always on new records, only on existing

  # records if the .password attribute isn't blank.

  def perform_password_validation?

    self.new_record? ? true : !self.password.blank?

  end

end

Api key (or any kind of key) generator

leethal (August Lilleaas) — Mon, 15 Oct 2007 13:03:21 GMT

Generates a random key for API neatness.



class KeyGenerator

  require "digest/sha1"

  def self.generate(length = 10)

    Digest::SHA1.hexdigest(Time.now.to_s + rand(12341234).to_s)[1..length]

  end

end