April 28, 2008 7 Comments

Lazy men’s rails plugin - mydry

I have been using this little plugin I wrote for some time now.

The main idea is that I always start working in the migrations, and there I define: not null fields, length for string fields, what fields are numbers and what are not, references to other models (this at least can be guessed with the _id ending), unique fields or field groups and things like that.

After the migration is executed, I need to rewrite almost it all, with even more information in the model, for example: the maximum length for a string field is not enough anymore, now you need the minimum length too.

And I really do not like idea of doing the same thing more than once (I think some of you agree with me, even if you do not agree with my solution).

To solve this problem, I created this little plugin, that is really a generator

You want to see some code? So, let’s start with a migration: ./script/generate migration example

class Example < ActiveRecord::Migration
  def self.up
    create_table :examples do |t|
      t.string :name, :null =&gt; false
      t.text :description
      t.integer :a_number
      t.references :example
    end
  end
 
  def self.down
    drop_table :examples
  end
end

Now, let’s run rake db:migrate && ./script/generate drymodel example
And it will generate the following code for the model:

class Example < ActiveRecord::Base
  #Relationships
  belongs_to :example
  #Validations
  validates_presence_of :name
  validates_numericality_of :a_number, :allow_nil =&gt; true
  validates_length_of :name, :maximum =&gt; 255, :allow_nil =&gt; true
  validates_associated :example, :allow_nil =&gt; true
end

Up to now, it generates validations for uniques, non nulls, numerics, associations, …
pretty much, every thing that you have already wrote on the migration.
Liked it?

to install, just add the github gem source (you need to do it only once):
gem sources -a http://gems.github.com/

and to install the plugin gem:
gem install urubatan-mydry_generator

Now you are ready to play!
If you want to take a look at the code, it is hosted in GitHub.
There is also a dryscaffold generator, that will do the same as the standard scaffold (with REST and all), but it list the columns from the database and you do not need to name them on the command line.
But I do not think it is that useful

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7 comments so far

Plugins para rails e grails | Blog do Urubatan April 28, 2008 12:37 pm

[…] Para quem é tão preguiçoso quanto eu, eu criei um plugin para o rails que reutiliza tudo (ou quase) o que você ja definiu na migration para gerar o model, o nome do plugin é mydry. […]
Celestino Gomes April 29, 2008 8:50 pm

Ainda não usei, mas pelo que já vi é muito legal! Parabéns!
Hallison Batista April 30, 2008 5:33 pm

Puts … como não pensaram nisso antes … Já havia pensado em algo parecido, mas não através de um generate. Perfeito. Provavelmente será incluído no Core. Parabéns!!!
Nome do Jogo » Artigo » Rails Podcast Brasil - Epis May 1, 2008 11:24 am

[…] Lazy men
Percio May 8, 2008 4:24 pm

Hey urubatan

Seu trabalho parece ser perfeito, mas infelizmente não consigo instala-lo no meu PC.

Aparece essa mensagem de erro :
Error fetching http://github.com:
getaddrinfo: no address associated with hostname (socketerror)
getting size of http://gems.github.com/Marshal.4.8

Agradeço antecipadamente pela atenção
Percio May 8, 2008 4:26 pm

Hey urubatan

Seu trabalho parece ser perfeito, mas infelizmente não consigo instala-lo no meu PC.

Aparece essa mensagem de erro :
Error fetching http://github.com:
getaddrinfo: no address associated with hostname (socketerror)
getting size of http://gems.github.com/Marshal.4.8

Agradeço antecipadamente pela atenção

Ah! esqueci de dizer que meu sistema operacional é o Ruindows XP SP2
Urubatan May 9, 2008 9:07 pm

ouvi falar de algumas pessoas que tiveram problemas com o github como source de gems, a solução foi atualizar o gem
gem update –system

se não funcionar também é possível instalar como plugin, é só baixar o tar na página do projeto e descompactar em /vendor/plugins que também funciona