Kolodvor

Divisible

vlado — Sat, 26 Mar 2011 07:59:01 +0000

I just published my first ruby gem on rubygems.org. It is a simple gem that is useful in case you need to find out if one number is divisible by another.

Usage

  9.divisible_by(3) # => true
  10.divisible_by(3) # => false
  12.divisible_by(3) # => true
  12.divisible_by(4) # => true
  15.divisible_by(4) # => false

Same can be done with

  Divisible.check(9, 3) # => true
  Divisible.check(10, 3) # => false
  Divisible.check(12, 3) # => true
  Divisible.check(12, 4) # => true
  Divisible.check(15, 4) # => false

Installation

  gem install divisible

For more info go to https://github.com/vlado/divisible

Number of workdays between two dates

vlado — Sun, 01 Aug 2010 21:55:34 +0000

It is pretty simple to get number of work days between two dates. For example we can get the number of workdays in this month.

  start_date = Date.civil(2010, 8, 1)
  end_date = Date.civil(2010, 8, 31)
  workdays = (start_date..end_date).select { |day| ![0, 6].include?(day.wday) }.size

Please note that this doesn’t include any check for holidays, you’ll need to figure that yourself (if you have need for that at all).

For more info see Array#select and Date#wday methods.

MarkItUp: Rails plugin that turns any textarea into a markup editor

vlado — Mon, 05 Jul 2010 16:14:09 +0000

I recently published a plugin that helps you turn any textarea into a markup editor. It is based on excellent markItUp! jQuery plugin.

Example

The most simple usage with preset defaults



  <%= javascript_include_tag "path/to/jquery" %>
  <%= mark_it_up '#miu_test' %>


  <%= form_tag do %>
    <%= text_area_tag "miu_test" %>
  <% end %>

You can see a lot more cool examples in action on markitup.cingel.hr.

More info

markitup.cingel.hr
github.com/cingel/mark_it_up

Simple Search Rails plugin

vlado — Sat, 26 Jun 2010 08:31:11 +0000

SimpleSearch brings simple search to ActiveRecord. It ads simple_search named scope that accepts query as parameter.

The idea is that you provide the query and plugin does the rest (splits query to keywords and compose where statement).

This can be very useful in case you just want to filter list of records by some query, you have autocomplete field, … or something similar.

Example

View

  <% form_tag request.path, :method => 'get' do %>
    <%= text_field_tag :query, params[:query] %>
  <% end %>

Model

  class User < ActiveRecord::Base
    acts_as_simply_searchable
  end

  # Columns: id, login, email, crypted_password, salt

Controller

  class UsersController < ApplicationController
    def index
      @users = User.simple_search(params[:query]).all
    end
  end

Query examples

Simple query

  User.simple_search("vlado")
  # => SELECT * FROM "users" WHERE (users.id LIKE '%vlado%' OR users.login LIKE '%vlado%' OR users.email LIKE '%vlado%' OR users.crypted_password LIKE '%vlado%' OR users.salt LIKE '%vlado%')

You can also provide :columns => :column1, :column2, ... option to limit search only to those columns

  class User < ActiveRecord::Base
    acts_as_simply_searchable :columns => :login, :email
  end

  User.simple_search("vlado")
  # => SELECT * FROM "users" WHERE (users.login LIKE '%vlado%' OR users.email LIKE '%vlado%')

More complex query

  User.simple_search("vlado, cingel")
  # will search for users matching 'vlado' and 'cingel' keywords
  # => SELECT * FROM "users" WHERE ((users.login LIKE '%vlado%' OR users.email LIKE '%vlado%') AND (users.login LIKE '%cingel%' OR users.email LIKE '%cingel%'))

NOTE: With proper use of indexes this plugin can work quite well in most cases, but in case you have a large and complex database it is usually much better idea to use some search daemon like Thinking Sphinx.

More info

http://github.com/cingel/simple_search

Flood

vlado — Tue, 22 Jun 2010 20:47:23 +0000

My neighbourhood was hit by flood today. We managed to prevent the water from entering the house, but it was a great reminder how powerful mother nature really is

If you wanna see more, click here.

Create new app with specific Rails version

vlado — Thu, 25 Feb 2010 11:09:50 +0000

I recently installed Rails 3 beta release but I needed to create new app with the 2.3.5. version. I was searching for a way to do that and I found this

  rails _2.3.5_ appname

Unfortunately this will produce an error similar to this

  /usr/local/lib/ruby/site_ruby/1.8/rubygems.rb:827:in `report_activate_error': RubyGem version error: railties(3.0.0.beta not = 2.3.5) (Gem::LoadError)
	from /usr/local/lib/ruby/site_ruby/1.8/rubygems.rb:261:in `activate'
	from /usr/local/lib/ruby/site_ruby/1.8/rubygems.rb:68:in `gem'
	from /usr/local/bin/rails3:18

To fix this first run

  which rails

and you will get a path to your rails executable, in my case this is /usr/local/bin/rails.

Then copy rails to rails3.

  sudo cp /usr/local/bin/rails /usr/local/bin/rails3

Then open this file in your text editor (TextMate in my case).

  mate /usr/local/bin/rails

and replace two last lines so that your file now looks like

  require 'rubygems'

  version = ">= 0"

  if ARGV.first =~ /^_(.*)_$/ and Gem::Version.correct? $1 then
    version = $1
    ARGV.shift
  end

  gem 'rails', version
  load 'rails'

Thats it, now you can create your app with specific Rails version with

  rails _2.3.5_ appname

View man documentation in Preview

vlado — Fri, 12 Feb 2010 08:12:12 +0000

If you are on OSX you can easily open man documentation using Preview. Just replace ls with command you would like to see documentation for.

 man -t "ls" | open -f -a /Applications/Preview.app/

If you plan to do this often, you can make your life much easier by putting this inside your .bash_profile.

 pman ()
 {
   man -t "${1}" | open -f -a /Applications/Preview.app/
 }

Now you can use following to view documentation in Preview

 pman ls

Credit goes to John W. Long.

Ruby library for parsing, validating and formatting phone numbers

vlado — Mon, 04 Jan 2010 16:19:39 +0000

Tomislav Car has just released Phone, Ruby library for phone number parsing, validation and formatting. It should save you a lot of time if you need any of the following:

* you have area where users input phone numbers in many different formats
* output phone numbers in specific format
* you need to send SMS messages from your app
* …

You can initialize new Phone object with Phone.new

  Phone.new('5125486', '91', '385')

  Phone.new(:number => '5125486', :area_code => '91', :country_code => '385')

Parsing is done using Phone.parse method

    Phone.parse '091/512-5486', :country_code => '385'
    Phone.parse '(091) 512 5486', :country_code => '385'

It is smart to set default contry code first so you don’t have to provide it as option every time

    Phone.default_country_code = '385'
    Phone.parse '091/512-5486'
    Phone.parse '(091) 512 5486'

Fow now, Phone works only for Croatian, Slovenian, Bosnian and Serbian phone numbers, but Tomislav is collecting data to support other countries.

Go check it out

Set focus on first field with Prototype

vlado — Sat, 02 Jan 2010 14:32:02 +0000

If you are using jQuery see this post.

To set focus on first text field with Prototype I prefer something like this

  var firstField = $$('input:text:visible').first();
  if (firstField)
    firstField.focus();

but you can also try with Form.focusFirstElement or Form.findFirstElement

Rails, CSRF and Ajax requests

vlado — Sat, 02 Jan 2010 00:36:03 +0000

Rails protects controller actions from CSRF (Cross-Site Request Forgery) attacks with a token based on a random string stored in the session. The token parameter is named authenticity_token by default and will be embedded in all forms and Ajax requests generated by Rails.

You should also add this token to all Ajax request that you hand coded. As suggested in Rails documentation you can add this line in head section.

  <%= javascript_tag "window._token = '#{form_authenticity_token}'" %>;

and then add authenticity_token to parameters option of Ajax requests

  new Ajax.Request('/some/url', {
    parameters: "foo=bar&authenticity_token="+_token
  });

Remote forgery protection plugin

This can get tedious if you have a lot of Ajax requests so I wrote a simple plugin that adds authenticity token to all Ajax requests automatically.

You can install it with

  script/plugin install git://github.com/vlado/remote_forgery_protection.git

Now all you have to do is add this line inside head section of you’re layout

  <%= remote_forgery_protection %>

and all non GET Ajax request will have authenticity_token parameter automatically included.

Magic is done by wrapping Ajax.Base using Function#wrap method so this will work only if you are using Prototype.
I plan to add support for other libraries (if there is interest) in the future so keep in touch.

Remote forgery protection currently supports Prototype, jQuery and ExtJS. Let me know if you would like to see it working with some other library

Plugin page: http://github.com/vlado/remote_forgery_protection

More info:
api.rubyonrails.org/classes/ActionController/RequestForgeryProtection/ClassMethods.html
isc.sans.org/diary.html?storyid=1750
en.wikipedia.org/wiki/Cross-site_request_forgery
opensoul.org/2008/10/24/ajax-and-request-forgery-protection