Give Us a create Method

When your application gets executed for the first time, think of how much it will help people if you have your application set up the database for them. But we have to remember that these same people will want to point that database wherever they please.

Add a create method to your application's module which builds the schema for us. The code should look like this:

require 'camping/db'
module Blog::Models
  class CreateBlog < V 0.1
    def self.up
      create_table :blog_posts, :force => true do |t|
        t.column :user_id,  :integer, :null => false
        t.column :title,    :string,  :limit => 255
        t.column :body,     :text
      end
    end
  end
end

def Blog.create
  Blog::Models.create_schema
end

Before Camping version 1.5 we didn't have nice migrations and you would have to hack it up yourself. Your PostAmble would then look like this:

 #!ruby
 def Blog.create
   unless Blog::Models::Post.table_exists?
     ActiveRecord::Schema.define do
       create_table :blog_posts, :force => true do |t|
         t.column :user_id,  :integer, :null => false
         t.column :title,    :string,  :limit => 255
         t.column :body,     :text
       end
     end
     Blog::Models::Post.reset_column_information
   end
 end 
        
 if __FILE__ == $0
   Blog::Models::Base.establish_connection :adapter => 'sqlite3', :database => 'blog.db'
   Blog::Models::Base.logger = Logger.new('camping.log')
   Blog.create
   puts Blog.run
 end 

The create method checks for the existence of the blog_posts table. If none, it creates the database.

If you use table_exists?, be sure to reset_column_information after the schema is created. Consider that when table_exists? is used, a blank schema is read as that table's column information.

In the PostAmble, the Blog.create command gets fired just before run. The commandline camping tool also fires create once before starting its request loop.

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