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Defining your model
Model definition in Clear is done by inclusion of the Clear::Model module in your class. Assuming we have this table in PostgreSQL:
CREATE TABLE articles (
id serial NOT NULL PRIMARY KEY,
name text NOT NULL,
description text
);
The definition of this model is straight forward:
article.cr
class Article
include Clear::Model
column name : String
column description : String?
column id : Int32, primary: true, presence: false
end
Cut step by step, this is what happens:
First, we include all the magic of Clear in our class:
include Clear::Model
Second, we define
name column as String. Clear will map automatically the column to the model attribute. column name : String
Third, we define
description . We defined descriptionas NULLABLE in our database. To reflect this choice, we add Nilable ? operator to our column.column description : String?
Finally, we define
id as our primary key for this model. While being declared as NOT NULL, the column is defined with a default value in PostgreSQL. Therefore, we tell Clear to not check value presence on save/validate by adding presence: false to the column definition.column id : Int32, primary: true, presence: false
You may now use your model :
a = Article.new({name: "A superb article!" })
a.description = "This is a master piece!"
a.save!
puts "Article has been properly saved as id=#{a.id}"
By default, Clear will inflect the model name and use plural lower case version of the model name as table name (here
articles).You may want to override this behavior, by redefining
self.table :class Model::Customer
include Clear::Model
self.table = "clients" #< Different from infered "model_customers" table.
# ...
end
Next article is covering deeply the column definition and its subtleties.
Last modified 3yr ago