Run your Ruby on Rails app on Google app engine .

Yeah its possible to run RoR base application on GAE/J Thanks to jruby .

Limitations :

NO activerecord
10000 files maximum
10 MB max file size

Steps

you should have jruby already jruby 1.3 =< installed

1: Install rails , warbler and appengine-apis

Jruby -S gem install  rails  warbler appengine-apis

2: checkout template rails app with datamapper

git clone git://github.com/dkubb/datamapper-on-rails.git

3: comment out the following lines in config/environment.rb

config.gem ‘rails’ config.gem ‘appengine-apis’

4: change to you app dir

5: pluginize your app

jruby -S warble pluginize

6: generate configs

jruby -S warble config

7: edit config/warble.rb

config.webxml.jruby.min.runtimes = 1 config.webxml.jruby.max.runtimes = 1 config.webxml.jruby.init.serial = true config.java_libs = []

8: generate war

jruby -S warble

module Spec
  module Rails
    module Matchers

      # check if the xpath exists one or more times
      class HaveXpathText
        def initialize(xpath,text)
          @xpath = xpath
          @text = text
          @text_returned = "" 
        end

        def matches?(response)
          @response = response
          doc = response.is_a?(Hpricot::Doc) ? response : Hpricot::XML(@response)
          begin

            @text_returned= (doc/@xpath).inner_text.strip
            if  @text_returned == @text.to_s
              true
            else
              false
            end
          rescue
            return  false
          end
        end

        def failure_message
          #          "Did not match expected xpath  #{@xpath} text #{@text}" 
          "Did not match expected xpath  #{@xpath} text #{@text_returned} with #{@text}" 
        end

        def negative_failure_message
          "Did find unexpected xpath  #{@xpath} text #{@text}" 
        end

        def description
          "match the xpath expression text #{@xpath}" 
        end
      end

      def have_xpath_text(xpath,text)
        HaveXpathText.new(xpath,text)
      end
  end
end

Rspec

Ruby Behavior driven development is Rpec. We will explore how to write specs with rspecs . we will not use yml fixture . yml fixtures sucks instead we use machinist and will use mocha as mocking framework

I assume you are on Mac or Linux .

First install rspec

sudo gem install rspec

then install rpsec-rails

sudo gem install rspec-rails

rails my_app

cd my_app

ruby script/generate rspec

cd spec

spec folder is home folder for all of you spec data for you app

So here is Mephisto xmlrpc plugin for Mephisto release 0.8 and for Mephisto Edge.

I  have ported original Mephisto_xmlrpc plugin to work with Mephisto 0.8 and Mephisto edge.

The Original plugin was not compatible with most of the Desktop blogging tool if you use metaweblog api. this plugin working with almost all popular blogging tools like ecto, marsedit, blogtk, gnome-blog etc. , even with google reader.

checkout Mephisto xmlrpc plugin from subversion, this is available two flavors .

for Mephisto release 0.8

script/plugin install http://svn.railshacks.com/projects/mephisto/plugins/mephisto_xmlrpc_0.8

for Mephisto edge

script/plugin install http://svn.railshacks.com/projects/mephisto/plugins/mephisto_xmlrpc_edge

To install Mephisto xmlrpc plugin

follow these steps

1:  edit file app/controllers/application/error.rb

locate these lines 

rescue_from ActiveRecord::RecordNotFound,        :with => :render_admin_not_found
rescue_from ActionController::UnknownController, :with => :render_admin_not_found
rescue_from ActionController::UnknownAction,     :with => :render_admin_not_found

change these lines to

rescue_from ::ActiveRecord::RecordNotFound,        :with => :render_admin_not_found
rescue_from ::ActionController::UnknownController, :with => :render_admin_not_found
rescue_from ::ActionController::UnknownAction,     :with => :render_admin_not_found

save the file .

2:  checkout action web service from svn repo. into vendor/rails folder.     

svn co    http://svn.rubyonrails.org/rails/ousted/actionwebservice/

3.  restart your server 

Now you have working xmlrpc service at your server .

if you face any problem  installing/using this plugin feel free to ask .

Mephisto has always been my favourite rails publishing system , few days back I switched to mephisto edge, later i found most of mephisto plugins are broken on mephisto edge because mephisto edge is using rails engine system ,

So I ported Stephen Caudill's existing mephisto sitemap plugin on mephisto edge and now its available at http://svn.railshacks.com/projects/mephisto/plugins/mephisto_sitemap/

Currently I am looking at other plugins that is not compatible with mephisto edge , As soon as i complete I will make it available for public download

if you face any problem please make a comment here

So you want to get notified when you get exception on production application environment , lets do in three easy steps

1: create a action mailer model

class Mymailer '
    @subject            = "[Error] exception in #{env['REQUEST_URI']}"
    @sent_on            = time
    @body["exception"]  = exception 
    @body["trace"]      = trace  
    @body["session"]    = session 
    @body["params"]     = params 
    @body["env"]        = env  
    content_type("text/html")  
  end

end

2: define this method in you application.rb file

def log_error(exception)
    super(exception)
    begin
      if ENV['RAILS_ENV'] == 'production'
        Notifier.deliver_error_page(exception,
          clean_backtrace(exception),
          @session.instance_variable_get("@data"),
          @params,
          @request.env)
      end
    rescue => e
      logger.error(e)
    end
  end

3: create a view file  view/mymailer/error_mail.html.erb


now you have access to these files , you can format your mail as you feel like

@body["exception"]  # exception
@body["trace"]      # trace   
@body["session"]    # session
@body["params"]     # params
@body["env"]        # env

now you have working exception handling system

if face any problem make a comment here

1. Mephisto
2. Typo
3. Rubricks
4. Radiant
5. Railfrog

Its a piece of cake developing applications that run on multitude of Database management solutions. All you need to keep Database schema scripts handy. Here is how you do it using rails scripts:

ruby script\generate migration Contact

This will create an empty file in db/migrate folder for contact table. You need to fill it now with the fields you want for eg:

class Contact < ActiveRecord::Migration def self.up create_table :contacts do |table| table.column :first_name, :string table.column :last_name, :string table.column :email, :string table.column :phone, :string table.column :address, :string end end def self.down end end

ruby script\generate scaffold Contact

Ok.. just found what I was looking for. Pretty detailed document for this: http://rubyonrails.org/api/classes/ActiveRecord/Migration.html

Now, apply the migration

rake migrate

Now, generate model and controller for Contact

ruby script\generate scaffold Contact

I got this error today while deploying rails application on running lighttpd server. Errno::ENOENT (No such file or directory – getcwd) I replaced application directory without stopping lighty and got error while trying accessing app via browser. I went off by merely restarting lighthttpd :)

Seems like server creates/uses some file “within” rails app folder which got erased while replacing the folder.

page.redirectto :action => ‘thanks’, :p1 => @gresp.params[”code”], :p2 => @rid

page.redirect_to :action => ‘thanks’, :p1 => @g_resp.params[”_code”], :p2 => @r_id

You might be feeling annoyed with this problem. (I do) Problem could be:

your local source cache Example: /usr/lib/ruby/gems/1.8/source_cache

; try removing this file (Your path might be different than above given; check your path first using #gem env) If this does not solves your problem

check your env var REMOTE SOURCES (#gem env)

If it is not gems.rubyforge.org then use following command to install:

gem install -r gem_name –source http://gems.rubyforge.org

If this does not solves your problem(is your internet down?)

Borrow gem files from your friend and install them without -r option.

gem install /path_to/gemname.gem