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diff --git a/railties/guides/source/active_resource_basics.textile b/railties/guides/source/active_resource_basics.textile deleted file mode 100644 index 37abb8a640..0000000000 --- a/railties/guides/source/active_resource_basics.textile +++ /dev/null @@ -1,120 +0,0 @@ -h2. Active Resource Basics - -This guide should provide you with all you need to get started managing the connection between business objects and RESTful web services. It implements a way to map web-based resources to local objects with CRUD semantics. - -endprologue. - -WARNING. This Guide is based on Rails 3.0. Some of the code shown here will not work in earlier versions of Rails. - -h3. Introduction - -Active Resource allows you to connect with RESTful web services. So, in Rails, Resource classes inherited from +ActiveResource::Base+ and live in +app/models+. - -h3. Configuration and Usage - -Putting Active Resource to use is very similar to Active Record. It's as simple as creating a model class -that inherits from ActiveResource::Base and providing a <tt>site</tt> class variable to it: - -<ruby> -class Person < ActiveResource::Base - self.site = "http://api.people.com:3000/" -end -</ruby> - -Now the Person class is REST enabled and can invoke REST services very similarly to how Active Record invokes -life cycle methods that operate against a persistent store. - -h3. Reading and Writing Data - -Active Resource make request over HTTP using a standard JSON format. It mirrors the RESTful routing built into Action Controller but will also work with any other REST service that properly implements the protocol. - -h4. Read - -Read requests use the GET method and expect the JSON form of whatever resource/resources is/are being requested. - -<ruby> -# Find a person with id = 1 -person = Person.find(1) -# Check if a person exists with id = 1 -Person.exists?(1) # => true -# Get all resources of Person class -Person.all -</ruby> - -h4. Create - -Creating a new resource submits the JSON form of the resource as the body of the request with HTTP POST method and parse the response into Active Resource object. - -<ruby> -person = Person.create(:name => 'Vishnu') -person.id # => 1 -</ruby> - -h4. Update - -To update an existing resource, 'save' method is used. This method make a HTTP PUT request in JSON format. - -<ruby> -person = Person.find(1) -person.name = 'Atrai' -person.save -</ruby> - -h4. Delete - -'destroy' method makes a HTTP DELETE request for an existing resource in JSON format to delete that resource. - -<ruby> -person = Person.find(1) -person.destroy -</ruby> - -h3. Validations - -Module to support validation and errors with Active Resource objects. The module overrides Base#save to rescue ActiveResource::ResourceInvalid exceptions and parse the errors returned in the web service response. The module also adds an errors collection that mimics the interface of the errors provided by ActiveModel::Errors. - -h4. Validating client side resources by overriding validation methods in base class - -<ruby> -class Person < ActiveResource::Base - self.site = "http://api.people.com:3000/" - - protected - - def validate - errors.add("last", "has invalid characters") unless last =~ /[a-zA-Z]*/ - end -end -</ruby> - -h4. Validating client side resources - -Consider a Person resource on the server requiring both a first_name and a last_name with a validates_presence_of :first_name, :last_name declaration in the model: - -<ruby> -person = Person.new(:first_name => "Jim", :last_name => "") -person.save # => false (server returns an HTTP 422 status code and errors) -person.valid? # => false -person.errors.empty? # => false -person.errors.count # => 1 -person.errors.full_messages # => ["Last name can't be empty"] -person.errors[:last_name] # => ["can't be empty"] -person.last_name = "Halpert" -person.save # => true (and person is now saved to the remote service) -</ruby> - -h4. Public instance methods - -ActiveResource::Validations have three public instance methods - -h5. errors() - -This will return errors object that holds all information about attribute error messages - -h5. save_with_validation(options=nil) - -This validates the resource with any local validations written in base class and then it will try to POST if there are no errors. - -h5. valid? - -Runs all the local validations and will return true if no errors. |