File: README.txt

# README.txt

Path: | README.txt
Last Update: | Tue Mar 03 00:22:22 -0700 2009

This is a DataMapper plugin that provides validations for DataMapper model classes.

## Setup

DataMapper validation capabilities are automatically available when you ‘require dm-validations’ into your application.

More specifically, DataMapper::Validate is automatically included into DataMapper::Resource when you require dm-validations.

## Specifying Model Validations

There are two primary ways to implement validations for your models:

1) Placing validation methods with properties as params in your class

       definitions like:
       - validates_length :name
       - validates_length [:name, :description]

2) Using auto-validations, please see DataMapper::Validate::AutoValidate

An example class with validations declared:

      require 'dm-validations'

      class Account
        include DataMapper::Resource

        property :name, String
        validates_length :name
      end

See all of the DataMapper::Validate module‘s XYZValidator(s) to learn about the complete collections of validators available to you.

## Validating

DataMapper validations, when included, alter the default save/create/update process for a model. Unless you specify a context the resource must be valid in the :default context before saving.

You may manually validate a resource using the valid? method, which will return true if the resource is valid, and false if it is invalid.

In addition to the valid? method, there is also an all_valid? method that recursively walks both the current object and its associated objects and returns its true/false result for the entire walk.

## Working with Validation Errors

If your validators find errors in your model, they will populate the DataMapper::Validate::ValidationErrors object that is available through each of your models via calls to your model‘s errors method.

For example:

      my_account = Account.new(:name => "Jose")
      if my_account.save
        # my_account is valid and has been saved
      else
        my_account.errors.each do |e|
          puts e
        end
      end

See DataMapper::Validate::ValidationErrors for all you can do with your model‘s errors method.

## Contextual Validations

DataMapper Validations also provide a means of grouping your validations into contexts. This enables you to run different sets of validations under … different contexts.

TO BE ADDED… For now, see

[Validate]