rails - bundle exec

"It’s worth noting that typing in rake foo (or anyexecutable foo) in the presence of aGemfile.lock, and expecting it to execute in the bundler sandbox doesn’t make any sense" - Yahuda


Ex: "rake middleware" should be replaced as "bundle exec rake middleware"

Testing your email notifications with MailCatcher.

    Often its hard to test email notifications sent from our application. MailCatcher is a gem which helps you to check those mails sent from your application.
Install the gem as 'gem install mailcatcher' and run 'mailcatcher' on your console. This  will start two servers. One smtp server(on 1025 port), use this server to sent mails. Another server, web server, helps us to view the 'sent' email on our browser 'http://localhost:1080/'. I tested it on Chrome 5.

Art of Light: plugin for loading application constants in rails.

Art of Light: plugin for loading application constants in rails.

plugin for loading application constants in rails.

https://github.com/shilesh/app_config


I have created a simple plugin which could be helpful in your rails projects. It is available at https://github.com/shilesh/app_config . This plugin, once installed , loads constants from a config file, while the application gets initialized (server start/restart, rails console etc ...). 

There will be situations when application specific constants are required in our application. Which we could configure as needed.

Summary:
=======

This plugin helps to load values from a config file(yml) file based on the 

environment, with out writing extra code. ie: if you have a config file as 'app_config.yml' and has values in it as title: 'Caption'.The plugin helps you to call as "AppConfig::TITLE". If your config file name is 'ror_values.yml' then the values can be accessed as RorValue::TITLE". In short ::.

 

I have tested against ruby 1.9 and rails 3.0

How to use:
==========

1. Install the plugin.
2. This will create a folder 'app_config' inside 'config' folder of your rails application.
3. A mock config file, named 'app_config.yml', will be created with sample data.
4. User can edit the file with proper values.
5. The file name can be renamed
6. Based on the file name the namescope will be created to access the values( :: ).
7. Restart the server if you change the file name.
8. You can expect helpful error messages being raised on invalid access.
9. When you un-install the files in config/app_config/* will be retained, 
10. expecting that it would contain useful data. You can manually delete it if needed.

    I have tested it against rails 3.0.x and 2.3.8 .

exception handling in ruby

Normally we don't explicitly specify the Exception type while 'rescue' ing it. ex:

begin

  raise 'alert'

rescue => e

  p "Error"

end

=> Error

Everything is fine here, But look at another case,

begin

  require 'IamNotThere'

rescue => e

  p "Error"

end

=> LoadError: no such file to load -- IamNotThere

Never expected ?, Our rescue block didn't handle this case.

begin

  require 'IamNotThere'

rescue Exception=> e

  p "Error"

end

=> Error

Again, everything is safe here.

So, It's always better narrow down our expectation or use 'Exception => e'. Default is 'StandardError'.


Heirarchy:

Exception

  NoMemoryError

  ScriptError

    LoadError

    NotImplementedError

    SyntaxError

  SignalException

    Interrupt

  StandardError

    ArgumentError

    IOError

      EOFError

    IndexError

    LocalJumpError

    NameError

    NoMethodError

    RangeError

      FloatDomainError

    RegexpError

    RuntimeError

    SecurityError

    SystemCallError

    SystemStackError

    ThreadError

    TypeError

    ZeroDivisionError

  SystemExit

  fatal

Test ruby after installation

Sounds silly and obvious, But if we miss to run './rubytest' after installing ruby(any software, especially from source) we might land in big trouble. We might get the feeling that it got installed correctly but it may not. A random check in irb could show something like "123.12".to_f => 123123.0 Which is wrong, But ruby was installed fine.

I got the tests ran successfully later and "123.12".to_f gave me 123.12.

Rails Scraps

Asynchronous ...mails using workling.

http://playtype.net/past/2008/11/11/sending_mail_asynchronously_in_rails/