Class: ActiveResource::Base

### Home Classes Methods

### In Files

- lib/active_resource/base.rb

### Parent

Object

### Methods

- ::all
- ::auth_type
- ::auth_type=
- ::build
- ::collection_path
- ::connection
- ::create
- ::delete
- ::element_path
- ::exists?
- ::find
- ::first
- ::format
- ::format=
- ::headers
- ::known_attributes
- ::last
- ::logger
- ::new
- ::new_element_path
- ::password
- ::password=
- ::prefix
- ::prefix=
- ::prefix_source
- ::proxy
- ::proxy=
- ::schema
- ::schema=
- ::set_prefix
- ::site
- ::site=
- ::ssl_options
- ::ssl_options=
- ::timeout
- ::timeout=
- ::user
- ::user=
- #==
- #clone
- #collection_path
- #connection
- #create
- #destroy
- #dup
- #element_path
- #encode
- #eql?
- #exists?
- #hash
- #id
- #id=
- #id_from_response
- #known_attributes
- #load
- #load_attributes_from_response
- #new?
- #new_element_path
- #new_record?
- #persisted?
- #reload
- #respond_to?
- #respond_to_without_attributes?
- #save
- #save!
- #schema
- #to_json
- #to_xml
- #update
- #update_attribute
- #update_attributes

### Included Modules

- ActiveResource::CustomMethods
- ActiveResource::Observing
- ActiveResource::Validations
- ActiveModel::Conversion
- ActiveModel::Serializers::JSON
- ActiveModel::Serializers::Xml

### Files

- README.rdoc

### Class/Module Index

Quicksearch

- ActiveResource
- ActiveResource::BadRequest
- ActiveResource::Base
- ActiveResource::ClientError
- ActiveResource::Connection
- ActiveResource::CustomMethods
- ActiveResource::CustomMethods::ClassMethods
- ActiveResource::CustomMethods::InstanceMethods
- ActiveResource::Errors
- ActiveResource::ForbiddenAccess
- ActiveResource::Formats
- ActiveResource::Formats::JsonFormat
- ActiveResource::Formats::XmlFormat
- ActiveResource::HttpMock
- ActiveResource::InvalidRequestError
- ActiveResource::LogSubscriber
- ActiveResource::Observing
- ActiveResource::Railtie
- ActiveResource::Request
- ActiveResource::ResourceConflict
- ActiveResource::ResourceGone
- ActiveResource::ResourceNotFound
- ActiveResource::Response
- ActiveResource::SSLError
- ActiveResource::ServerError
- ActiveResource::TimeoutError
- ActiveResource::UnauthorizedAccess
- ActiveResource::Validations

No matching classes.

# ActiveResource::Base

ActiveResource::Base is the main class for mapping RESTful resources as models in a Rails application.

For an outline of what Active Resource is capable of, see its README.

## Automated mapping

Active Resource objects represent your RESTful resources as manipulatable Ruby objects. To map resources to Ruby objects, Active Resource only needs a class name that corresponds to the resource name (e.g., the class Person maps to the resources people, very similarly to Active Record) and a `site` value, which holds the URI of the resources.

    class Person < ActiveResource::Base
      self.site = "http://api.people.com:3000/"
    end

Now the Person class is mapped to RESTful resources located at `http://api.people.com:3000/people/`, and you can now use Active Resource’s life cycle methods to manipulate resources. In the case where you already have an existing model with the same name as the desired RESTful resource you can set the `element_name` value.

    class PersonResource < ActiveResource::Base
      self.site = "http://api.people.com:3000/"
      self.element_name = "person"
    end

If your Active Resource object is required to use an HTTP proxy you can set the `proxy` value which holds a URI.

    class PersonResource < ActiveResource::Base
      self.site = "http://api.people.com:3000/"
      self.proxy = "http://user:password@proxy.people.com:8080"
    end

## Life cycle methods

Active Resource exposes methods for creating, finding, updating, and deleting resources from REST web services.

    ryan = Person.new(:first => 'Ryan', :last => 'Daigle')
    ryan.save                # => true
    ryan.id                  # => 2
    Person.exists?(ryan.id)  # => true
    ryan.exists?             # => true

    ryan = Person.find(1)
    # Resource holding our newly created Person object

    ryan.first = 'Rizzle'
    ryan.save                # => true

    ryan.destroy             # => true

As you can see, these are very similar to Active Record’s life cycle methods for database records. You can read more about each of these methods in their respective documentation.

### Custom REST methods

Since simple CRUD/life cycle methods can’t accomplish every task, Active Resource also supports defining your own custom REST methods. To invoke them, Active Resource provides the `get`, `post`, `put` and `\delete` methods where you can specify a custom REST method name to invoke.

    # POST to the custom 'register' REST method, i.e. POST /people/new/register.xml.
    Person.new(:name => 'Ryan').post(:register)
    # => { :id => 1, :name => 'Ryan', :position => 'Clerk' }

    # PUT an update by invoking the 'promote' REST method, i.e. PUT /people/1/promote.xml?position=Manager.
    Person.find(1).put(:promote, :position => 'Manager')
    # => { :id => 1, :name => 'Ryan', :position => 'Manager' }

    # GET all the positions available, i.e. GET /people/positions.xml.
    Person.get(:positions)
    # => [{:name => 'Manager'}, {:name => 'Clerk'}]

    # DELETE to 'fire' a person, i.e. DELETE /people/1/fire.xml.
    Person.find(1).delete(:fire)

For more information on using custom REST methods, see the ActiveResource::CustomMethods documentation.

## Validations

You can validate resources client side by overriding validation methods in the base class.

    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

See the ActiveResource::Validations documentation for more information.

## Authentication

Many REST APIs will require authentication, usually in the form of basic HTTP authentication. Authentication can be specified by:

### HTTP Basic Authentication

- putting the credentials in the URL for the `site` variable.

      class Person < ActiveResource::Base
        self.site = "http://ryan:password@api.people.com:3000/"
      end

- defining `user` and/or `password` variables

      class Person < ActiveResource::Base
        self.site = "http://api.people.com:3000/"
        self.user = "ryan"
        self.password = "password"
      end

For obvious security reasons, it is probably best if such services are available over HTTPS.

Note: Some values cannot be provided in the URL passed to site. e.g. email addresses as usernames. In those situations you should use the separate user and password option.

### Certificate Authentication

- End point uses an X509 certificate for authentication. `See ssl_options=` for all options.

      class Person < ActiveResource::Base
        self.site = "https://secure.api.people.com/"
        self.ssl_options = {:cert         => OpenSSL::X509::Certificate.new(File.open(pem_file))
                            :key          => OpenSSL::PKey::RSA.new(File.open(pem_file)),
                            :ca_path      => "/path/to/OpenSSL/formatted/CA_Certs",
                            :verify_mode  => OpenSSL::SSL::VERIFY_PEER}
      end

## Errors & Validation

Error handling and validation is handled in much the same manner as you’re used to seeing in Active Record. Both the response code in the HTTP response and the body of the response are used to indicate that an error occurred.

### Resource errors

When a GET is requested for a resource that does not exist, the HTTP `404` (Resource Not Found) response code will be returned from the server which will raise an ActiveResource::ResourceNotFound exception.

    # GET http://api.people.com:3000/people/999.xml
    ryan = Person.find(999) # 404, raises ActiveResource::ResourceNotFound

`404` is just one of the HTTP error response codes that Active Resource will handle with its own exception. The following HTTP response codes will also result in these exceptions:

- 200..399 - Valid response, no exception (other than 301, 302)

- 301, 302 - ActiveResource::Redirection

- 400 - ActiveResource::BadRequest

- 401 - ActiveResource::UnauthorizedAccess

- 403 - ActiveResource::ForbiddenAccess

- 404 - ActiveResource::ResourceNotFound

- 405 - ActiveResource::MethodNotAllowed

- 409 - ActiveResource::ResourceConflict

- 410 - ActiveResource::ResourceGone

- 422 - ActiveResource::ResourceInvalid (rescued by save as validation errors)

- 401..499 - ActiveResource::ClientError

- 500..599 - ActiveResource::ServerError

- Other - ActiveResource::ConnectionError

These custom exceptions allow you to deal with resource errors more naturally and with more precision rather than returning a general HTTP error. For example:

    begin
      ryan = Person.find(my_id)
    rescue ActiveResource::ResourceNotFound
      redirect_to :action => 'not_found'
    rescue ActiveResource::ResourceConflict, ActiveResource::ResourceInvalid
      redirect_to :action => 'new'
    end

### Validation errors

Active Resource supports validations on resources and will return errors if any of these validations fail (e.g., “First name can not be blank” and so on). These types of errors are denoted in the response by a response code of `422` and an XML or JSON representation of the validation errors. The save operation will then fail (with a `false` return value) and the validation errors can be accessed on the resource in question.

    ryan = Person.find(1)
    ryan.first # => ''
    ryan.save  # => false

    # When
    # PUT http://api.people.com:3000/people/1.xml
    # or
    # PUT http://api.people.com:3000/people/1.json
    # is requested with invalid values, the response is:
    #
    # Response (422):
    # <errors><error>First cannot be empty</error></errors>
    # or
    # {"errors":["First cannot be empty"]}
    #

    ryan.errors.invalid?(:first)  # => true
    ryan.errors.full_messages     # => ['First cannot be empty']

Learn more about Active Resource’s validation features in the ActiveResource::Validations documentation.

### Timeouts

Active Resource relies on HTTP to access RESTful APIs and as such is inherently susceptible to slow or unresponsive servers. In such cases, your Active Resource method calls could timeout. You can control the amount of time before Active Resource times out with the `timeout` variable.

    class Person < ActiveResource::Base
      self.site = "http://api.people.com:3000/"
      self.timeout = 5
    end

This sets the `timeout` to 5 seconds. You can adjust the `timeout` to a value suitable for the RESTful API you are accessing. It is recommended to set this to a reasonably low value to allow your Active Resource clients (especially if you are using Active Resource in a Rails application) to fail-fast (see en.wikipedia.org/wiki/Fail-fast) rather than cause cascading failures that could incapacitate your server.

When a timeout occurs, an ActiveResource::TimeoutError is raised. You should rescue from ActiveResource::TimeoutError in your Active Resource method calls.

Internally, Active Resource relies on Ruby’s Net::HTTP library to make HTTP requests. Setting `timeout` sets the `read_timeout` of the internal Net::HTTP instance to the same value. The default `read_timeout` is 60 seconds on most Ruby implementations.

### Public Class Methods

all(*args) click to toggle source

This is an alias for find(:all). You can pass in all the same arguments to this method as you can to `find(:all)`

    # File lib/active_resource/base.rb, line 802
    def all(*args)
      find(:all, *args)
    end

auth_type() click to toggle source

    # File lib/active_resource/base.rb, line 459
    def auth_type
      if defined?(@auth_type)
        @auth_type
      end
    end

auth_type=(auth_type) click to toggle source

    # File lib/active_resource/base.rb, line 465
    def auth_type=(auth_type)
      @connection = nil
      @auth_type = auth_type
    end

build(attributes = {}) click to toggle source

Builds a new, unsaved record using the default values from the remote server so that it can be used with RESTful forms.

#### Options

- `attributes` - A hash that overrides the default values from the server.

Returns the new resource instance.

    # File lib/active_resource/base.rb, line 680
    def build(attributes = {})
      attrs = connection.get("#{new_element_path}").merge(attributes)
      self.new(attrs)
    end

collection_path(prefix_options = {}, query_options = nil) click to toggle source

Gets the collection path for the REST resources. If the `query_options` parameter is omitted, Rails will split from the `prefix_options`.

#### Options

- `prefix_options` - A hash to add a prefix to the request for nested URLs (e.g., `:account_id => 19` would yield a URL like `/accounts/19/purchases.xml`).

- `query_options` - A hash to add items to the query string for the request.

#### Examples

    Post.collection_path
    # => /posts.xml

    Comment.collection_path(:post_id => 5)
    # => /posts/5/comments.xml

    Comment.collection_path(:post_id => 5, :active => 1)
    # => /posts/5/comments.xml?active=1

    Comment.collection_path({:post_id => 5}, {:active => 1})
    # => /posts/5/comments.xml?active=1

    # File lib/active_resource/base.rb, line 665
    def collection_path(prefix_options = {}, query_options = nil)
      prefix_options, query_options = split_options(prefix_options) if query_options.nil?
      "#{prefix(prefix_options)}#{collection_name}.#{format.extension}#{query_string(query_options)}"
    end

connection(refresh = false) click to toggle source

An instance of ActiveResource::Connection that is the base connection to the remote service. The `refresh` parameter toggles whether or not the connection is refreshed at every request or not (defaults to `false`).

    # File lib/active_resource/base.rb, line 535
    def connection(refresh = false)
      if defined?(@connection) || superclass == Object
        @connection = Connection.new(site, format) if refresh || @connection.nil?
        @connection.proxy = proxy if proxy
        @connection.user = user if user
        @connection.password = password if password
        @connection.auth_type = auth_type if auth_type
        @connection.timeout = timeout if timeout
        @connection.ssl_options = ssl_options if ssl_options
        @connection
      else
        superclass.connection
      end
    end

create(attributes = {}) click to toggle source

Creates a new resource instance and makes a request to the remote service that it be saved, making it equivalent to the following simultaneous calls:

    ryan = Person.new(:first => 'ryan')
    ryan.save

Returns the newly created resource. If a failure has occurred an exception will be raised (see `save`). If the resource is invalid and has not been saved then `valid?` will return `false`, while `new?` will still return `true`.

#### Examples

    Person.create(:name => 'Jeremy', :email => 'myname@nospam.com', :enabled => true)
    my_person = Person.find(:first)
    my_person.email # => myname@nospam.com

    dhh = Person.create(:name => 'David', :email => 'dhh@nospam.com', :enabled => true)
    dhh.valid? # => true
    dhh.new?   # => false

    # We'll assume that there's a validation that requires the name attribute
    that_guy = Person.create(:name => '', :email => 'thatguy@nospam.com', :enabled => true)
    that_guy.valid? # => false
    that_guy.new?   # => true

    # File lib/active_resource/base.rb, line 709
    def create(attributes = {})
      self.new(attributes).tap { |resource| resource.save }
    end

delete(id, options = {}) click to toggle source

Deletes the resources with the ID in the `id` parameter.

#### Options

All options specify prefix and query parameters.

#### Examples

    Event.delete(2) # sends DELETE /events/2

    Event.create(:name => 'Free Concert', :location => 'Community Center')
    my_event = Event.find(:first) # let's assume this is event with ID 7
    Event.delete(my_event.id) # sends DELETE /events/7

    # Let's assume a request to events/5/cancel.xml
    Event.delete(params[:id]) # sends DELETE /events/5

    # File lib/active_resource/base.rb, line 821
    def delete(id, options = {})
      connection.delete(element_path(id, options))
    end

element_path(id, prefix_options = {}, query_options = nil) click to toggle source

Gets the element path for the given ID in `id`. If the `query_options` parameter is omitted, Rails will split from the prefix options.

#### Options

`prefix_options` - A hash to add a prefix to the request for nested URLs (e.g., `:account_id => 19`

    would yield a URL like <tt>/accounts/19/purchases.xml</tt>).

`query_options` - A hash to add items to the query string for the request.

#### Examples

    Post.element_path(1)
    # => /posts/1.xml

    Comment.element_path(1, :post_id => 5)
    # => /posts/5/comments/1.xml

    Comment.element_path(1, :post_id => 5, :active => 1)
    # => /posts/5/comments/1.xml?active=1

    Comment.element_path(1, {:post_id => 5}, {:active => 1})
    # => /posts/5/comments/1.xml?active=1

    # File lib/active_resource/base.rb, line 623
    def element_path(id, prefix_options = {}, query_options = nil)
      prefix_options, query_options = split_options(prefix_options) if query_options.nil?
      "#{prefix(prefix_options)}#{collection_name}/#{URI.escape id.to_s}.#{format.extension}#{query_string(query_options)}"
    end

exists?(id, options = {}) click to toggle source

Asserts the existence of a resource, returning `true` if the resource is found.

#### Examples

    Note.create(:title => 'Hello, world.', :body => 'Nothing more for now...')
    Note.exists?(1) # => true

    Note.exists(1349) # => false

    # File lib/active_resource/base.rb, line 832
    def exists?(id, options = {})
      if id
        prefix_options, query_options = split_options(options[:params])
        path = element_path(id, prefix_options, query_options)
        response = connection.head(path, headers)
        response.code.to_i == 200
      end
      # id && !find_single(id, options).nil?
    rescue ActiveResource::ResourceNotFound, ActiveResource::ResourceGone
      false
    end

find(*arguments) click to toggle source

Core method for finding resources. Used similarly to Active Record’s `find` method.

#### Arguments

The first argument is considered to be the scope of the query. That is, how many resources are returned from the request. It can be one of the following.

- `:one` - Returns a single resource.

- `:first` - Returns the first resource found.

- `:last` - Returns the last resource found.

- `:all` - Returns every resource that matches the request.

#### Options

- `:from` - Sets the path or custom method that resources will be fetched from.

- `:params` - Sets query and prefix (nested URL) parameters.

#### Examples

    Person.find(1)
    # => GET /people/1.xml

    Person.find(:all)
    # => GET /people.xml

    Person.find(:all, :params => { :title => "CEO" })
    # => GET /people.xml?title=CEO

    Person.find(:first, :from => :managers)
    # => GET /people/managers.xml

    Person.find(:last, :from => :managers)
    # => GET /people/managers.xml

    Person.find(:all, :from => "/companies/1/people.xml")
    # => GET /companies/1/people.xml

    Person.find(:one, :from => :leader)
    # => GET /people/leader.xml

    Person.find(:all, :from => :developers, :params => { :language => 'ruby' })
    # => GET /people/developers.xml?language=ruby

    Person.find(:one, :from => "/companies/1/manager.xml")
    # => GET /companies/1/manager.xml

    StreetAddress.find(1, :params => { :person_id => 1 })
    # => GET /people/1/street_addresses/1.xml

## Failure or missing data

    A failure to find the requested object raises a ResourceNotFound
    exception if the find was called with an id.
    With any other scope, find returns nil when no data is returned.

    Person.find(1)
    # => raises ResourceNotFound

    Person.find(:all)
    Person.find(:first)
    Person.find(:last)
    # => nil

    # File lib/active_resource/base.rb, line 772
    def find(*arguments)
      scope   = arguments.slice!(0)
      options = arguments.slice!(0) || {}

      case scope
        when :all   then find_every(options)
        when :first then find_every(options).first
        when :last  then find_every(options).last
        when :one   then find_one(options)
        else             find_single(scope, options)
      end
    end

first(*args) click to toggle source

A convenience wrapper for `find(:first, *args)`. You can pass in all the same arguments to this method as you can to `find(:first)`.

    # File lib/active_resource/base.rb, line 789
    def first(*args)
      find(:first, *args)
    end

format() click to toggle source

Returns the current format, default is ActiveResource::Formats::XmlFormat.

    # File lib/active_resource/base.rb, line 488
    def format
      read_inheritable_attribute(:format) || ActiveResource::Formats::XmlFormat
    end

format=(mime_type_reference_or_format) click to toggle source

Sets the format that attributes are sent and received in from a mime type reference:

    Person.format = :json
    Person.find(1) # => GET /people/1.json

    Person.format = ActiveResource::Formats::XmlFormat
    Person.find(1) # => GET /people/1.xml

Default format is `:xml`.

    # File lib/active_resource/base.rb, line 479
    def format=(mime_type_reference_or_format)
      format = mime_type_reference_or_format.is_a?(Symbol) ?
        ActiveResource::Formats[mime_type_reference_or_format] : mime_type_reference_or_format

      write_inheritable_attribute(:format, format)
      connection.format = format if site
    end

headers() click to toggle source

    # File lib/active_resource/base.rb, line 550
    def headers
      @headers ||= {}
    end

known_attributes() click to toggle source

Returns the list of known attributes for this resource, gathered from the provided `schema` Attributes that are known will cause your resource to return ‘true’ when `respond_to?` is called on them. A known attribute will return nil if not set (rather than <t>MethodNotFound</tt>); thus known attributes can be used with `validates_presence_of` without a getter-method.

    # File lib/active_resource/base.rb, line 369
    def known_attributes
      @known_attributes ||= []
    end

last(*args) click to toggle source

A convenience wrapper for `find(:last, *args)`. You can pass in all the same arguments to this method as you can to `find(:last)`.

    # File lib/active_resource/base.rb, line 796
    def last(*args)
      find(:last, *args)
    end

logger click to toggle source

The logger for diagnosing and tracing Active Resource calls.

    # File lib/active_resource/base.rb, line 252
    cattr_accessor :logger

new(attributes = {}) click to toggle source

Constructor method for new resources; the optional `attributes` parameter takes a hash of attributes for the new resource.

#### Examples

    my_course = Course.new
    my_course.name = "Western Civilization"
    my_course.lecturer = "Don Trotter"
    my_course.save

    my_other_course = Course.new(:name => "Philosophy: Reason and Being", :lecturer => "Ralph Cling")
    my_other_course.save

    # File lib/active_resource/base.rb, line 962
    def initialize(attributes = {})
      @attributes     = {}.with_indifferent_access
      @prefix_options = {}
      load(attributes)
    end

new_element_path(prefix_options = {}) click to toggle source

Gets the new element path for REST resources.

#### Options

- `prefix_options` - A hash to add a prefix to the request for nested URLs (e.g., `:account_id => 19` would yield a URL like `/accounts/19/purchases/new.xml`).

#### Examples

    Post.new_element_path
    # => /posts/new.xml

    Comment.collection_path(:post_id => 5)
    # => /posts/5/comments/new.xml

    # File lib/active_resource/base.rb, line 640
    def new_element_path(prefix_options = {})
      "#{prefix(prefix_options)}#{collection_name}/new.#{format.extension}"
    end

password() click to toggle source

Gets the password for REST HTTP authentication.

    # File lib/active_resource/base.rb, line 444
    def password
      # Not using superclass_delegating_reader. See +site+ for explanation
      if defined?(@password)
        @password
      elsif superclass != Object && superclass.password
        superclass.password.dup.freeze
      end
    end

password=(password) click to toggle source

Sets the password for REST HTTP authentication.

    # File lib/active_resource/base.rb, line 454
    def password=(password)
      @connection = nil
      @password = password
    end

prefix(options={}) click to toggle source

Gets the prefix for a resource’s nested URL (e.g., `prefix/collectionname/1.xml`) This method is regenerated at runtime based on what the prefix is set to.

    # File lib/active_resource/base.rb, line 561
    def prefix(options={})
      default = site.path
      default << '/' unless default[-1..-1] == '/'
      # generate the actual method based on the current site path
      self.prefix = default
      prefix(options)
    end

prefix=(value = '/') click to toggle source

Sets the prefix for a resource’s nested URL (e.g., `prefix/collectionname/1.xml`). Default value is `site.path`.

    # File lib/active_resource/base.rb, line 578
    def prefix=(value = '/')
      # Replace :placeholders with '#{embedded options[:lookups]}'
      prefix_call = value.gsub(/:\w+/) { |key| "\#{URI.escape options[#{key}].to_s}" }

      # Clear prefix parameters in case they have been cached
      @prefix_parameters = nil

      silence_warnings do
        # Redefine the new methods.
        instance_eval             def prefix_source() "#{value}" end            def prefix(options={}) "#{prefix_call}" end, __FILE__, __LINE__ + 1
      end
    rescue Exception => e
      logger.error "Couldn't set prefix: #{e}\n  #{code}" if logger
      raise
    end

Also aliased as: set_prefix
prefix_source() click to toggle source

An attribute reader for the source string for the resource path prefix. This method is regenerated at runtime based on what the prefix is set to.

    # File lib/active_resource/base.rb, line 571
    def prefix_source
      prefix # generate #prefix and #prefix_source methods first
      prefix_source
    end

proxy() click to toggle source

Gets the proxy variable if a proxy is required

    # File lib/active_resource/base.rb, line 412
    def proxy
      # Not using superclass_delegating_reader. See +site+ for explanation
      if defined?(@proxy)
        @proxy
      elsif superclass != Object && superclass.proxy
        superclass.proxy.dup.freeze
      end
    end

proxy=(proxy) click to toggle source

Sets the URI of the http proxy to the value in the `proxy` argument.

    # File lib/active_resource/base.rb, line 422
    def proxy=(proxy)
      @connection = nil
      @proxy = proxy.nil? ? nil : create_proxy_uri_from(proxy)
    end

schema(&block) click to toggle source

Creates a schema for this resource - setting the attributes that are known prior to fetching an instance from the remote system.

The schema helps define the set of `known_attributes` of the current resource.

There is no need to specify a schema for your Active Resource. If you do not, the `known_attributes` will be guessed from the instance attributes returned when an instance is fetched from the remote system.

example: class Person < ActiveResource::Base

    schema do
      # define each attribute separately
      attribute 'name', :string

      # or use the convenience methods and pass >=1 attribute names
      string  'eye_colour', 'hair_colour'
      integer 'age'
      float   'height', 'weight'

      # unsupported types should be left as strings
      # overload the accessor methods if you need to convert them
      attribute 'created_at', 'string'
    end

end

p = Person.new p.respond_to? :name # => true p.respond_to? :age # => true p.name # => nil p.age # => nil

j = Person.find_by_name(‘John’) # <person><name>John</name><age>34</age><num_children>3</num_children></person> j.respond_to? :name # => true j.respond_to? :age # => true j.name # => ‘John’ j.age # => ‘34’ # note this is a string! j.num_children # => ‘3’ # note this is a string!

p.num_children # => NoMethodError

Attribute-types must be one of:

    string, integer, float

Note: at present the attribute-type doesn’t do anything, but stay tuned… Shortly it will also cast the value of the returned attribute. ie: j.age # => 34 # cast to an integer j.weight # => ‘65’ # still a string!

    # File lib/active_resource/base.rb, line 308
    def schema(&block)
      if block_given?
        schema_definition = Schema.new
        schema_definition.instance_eval(&block)

        # skip out if we didn't define anything
        return unless schema_definition.attrs.present?

        @schema ||= {}.with_indifferent_access
        @known_attributes ||= []

        schema_definition.attrs.each do |k,v|
          @schema[k] = v
          @known_attributes << k
        end

        schema
      else
        @schema ||= nil
      end
    end

schema=(the_schema) click to toggle source

Alternative, direct way to specify a `schema` for this Resource. `schema` is more flexible, but this is quick for a very simple schema.

Pass the schema as a hash with the keys being the attribute-names and the value being one of the accepted attribute types (as defined in `schema`)

example:

class Person < ActiveResource::Base

    schema = {'name' => :string, 'age' => :integer }

end

The keys/values can be strings or symbols. They will be converted to strings.

    # File lib/active_resource/base.rb, line 347
    def schema=(the_schema)
      unless the_schema.present?
        # purposefully nulling out the schema
        @schema = nil
        @known_attributes = []
        return
      end

      raise ArgumentError, "Expected a hash" unless the_schema.kind_of? Hash

      schema do
        the_schema.each {|k,v| attribute(k,v) }
      end
    end

set_prefix(value = '/') click to toggle source
Alias for: prefix=
site() click to toggle source

Gets the URI of the REST resources to map for this class. The site variable is required for Active Resource’s mapping to work.

    # File lib/active_resource/base.rb, line 375
    def site
      # Not using superclass_delegating_reader because don't want subclasses to modify superclass instance
      #
      # With superclass_delegating_reader
      #
      #   Parent.site = 'http://anonymous@test.com'
      #   Subclass.site # => 'http://anonymous@test.com'
      #   Subclass.site.user = 'david'
      #   Parent.site # => 'http://david@test.com'
      #
      # Without superclass_delegating_reader (expected behaviour)
      #
      #   Parent.site = 'http://anonymous@test.com'
      #   Subclass.site # => 'http://anonymous@test.com'
      #   Subclass.site.user = 'david' # => TypeError: can't modify frozen object
      #
      if defined?(@site)
        @site
      elsif superclass != Object && superclass.site
        superclass.site.dup.freeze
      end
    end

site=(site) click to toggle source

Sets the URI of the REST resources to map for this class to the value in the `site` argument. The site variable is required for Active Resource’s mapping to work.

    # File lib/active_resource/base.rb, line 400
    def site=(site)
      @connection = nil
      if site.nil?
        @site = nil
      else
        @site = create_site_uri_from(site)
        @user = uri_parser.unescape(@site.user) if @site.user
        @password = uri_parser.unescape(@site.password) if @site.password
      end
    end

ssl_options() click to toggle source

Returns the SSL options hash.

    # File lib/active_resource/base.rb, line 524
    def ssl_options
      if defined?(@ssl_options)
        @ssl_options
      elsif superclass != Object && superclass.ssl_options
        superclass.ssl_options
      end
    end

ssl_options=(opts={}) click to toggle source

Options that will get applied to an SSL connection.

- `:key` - An OpenSSL::PKey::RSA or OpenSSL::PKey::DSA object.

- `:cert` - An OpenSSL::X509::Certificate object as client certificate

- `:ca_file` - Path to a CA certification file in PEM format. The file can contrain several CA certificates.

- `:ca_path` - Path of a CA certification directory containing certifications in PEM format.

- `:verify_mode` - Flags for server the certification verification at begining of SSL/TLS session. (OpenSSL::SSL::VERIFY_NONE or OpenSSL::SSL::VERIFY_PEER is acceptable)

- `:verify_callback` - The verify callback for the server certification verification.

- `:verify_depth` - The maximum depth for the certificate chain verification.

- `:cert_store` - OpenSSL::X509::Store to verify peer certificate.

- `:ssl_timeout` -The SSL timeout in seconds.

    # File lib/active_resource/base.rb, line 518
    def ssl_options=(opts={})
      @connection   = nil
      @ssl_options  = opts
    end

timeout() click to toggle source

Gets the number of seconds after which requests to the REST API should time out.

    # File lib/active_resource/base.rb, line 499
    def timeout
      if defined?(@timeout)
        @timeout
      elsif superclass != Object && superclass.timeout
        superclass.timeout
      end
    end

timeout=(timeout) click to toggle source

Sets the number of seconds after which requests to the REST API should time out.

    # File lib/active_resource/base.rb, line 493
    def timeout=(timeout)
      @connection = nil
      @timeout = timeout
    end

user() click to toggle source

Gets the user for REST HTTP authentication.

    # File lib/active_resource/base.rb, line 428
    def user
      # Not using superclass_delegating_reader. See +site+ for explanation
      if defined?(@user)
        @user
      elsif superclass != Object && superclass.user
        superclass.user.dup.freeze
      end
    end

user=(user) click to toggle source

Sets the user for REST HTTP authentication.

    # File lib/active_resource/base.rb, line 438
    def user=(user)
      @connection = nil
      @user = user
    end

### Public Instance Methods

==(other) click to toggle source

Test for equality. Resource are equal if and only if `other` is the same object or is an instance of the same class, is not `new?`, and has the same `id`.

#### Examples

    ryan = Person.create(:name => 'Ryan')
    jamie = Person.create(:name => 'Jamie')

    ryan == jamie
    # => false (Different name attribute and id)

    ryan_again = Person.new(:name => 'Ryan')
    ryan == ryan_again
    # => false (ryan_again is new?)

    ryans_clone = Person.create(:name => 'Ryan')
    ryan == ryans_clone
    # => false (Different id attributes)

    ryans_twin = Person.find(ryan.id)
    ryan == ryans_twin
    # => true

    # File lib/active_resource/base.rb, line 1069
    def ==(other)
      other.equal?(self) || (other.instance_of?(self.class) && other.id == id && other.prefix_options == prefix_options)
    end

clone() click to toggle source

Returns a clone of the resource that hasn’t been assigned an `id` yet and is treated as a new resource.

    ryan = Person.find(1)
    not_ryan = ryan.clone
    not_ryan.new?  # => true

Any active resource member attributes will NOT be cloned, though all other attributes are. This is to prevent the conflict between any `prefix_options` that refer to the original parent resource and the newly cloned parent resource that does not exist.

    ryan = Person.find(1)
    ryan.address = StreetAddress.find(1, :person_id => ryan.id)
    ryan.hash = {:not => "an ARes instance"}

    not_ryan = ryan.clone
    not_ryan.new?            # => true
    not_ryan.address         # => NoMethodError
    not_ryan.hash            # => {:not => "an ARes instance"}

    # File lib/active_resource/base.rb, line 988
    def clone
      # Clone all attributes except the pk and any nested ARes
      cloned = attributes.reject {|k,v| k == self.class.primary_key || v.is_a?(ActiveResource::Base)}.inject({}) do |attrs, (k, v)|
        attrs[k] = v.clone
        attrs
      end
      # Form the new resource - bypass initialize of resource with 'new' as that will call 'load' which
      # attempts to convert hashes into member objects and arrays into collections of objects.  We want
      # the raw objects to be cloned so we bypass load by directly setting the attributes hash.
      resource = self.class.new({})
      resource.prefix_options = self.prefix_options
      resource.send :instance_variable_set, '@attributes', cloned
      resource
    end

destroy() click to toggle source

Deletes the resource from the remote service.

#### Examples

    my_id = 3
    my_person = Person.find(my_id)
    my_person.destroy
    Person.find(my_id) # 404 (Resource Not Found)

    new_person = Person.create(:name => 'James')
    new_id = new_person.id # => 7
    new_person.destroy
    Person.find(new_id) # 404 (Resource Not Found)

    # File lib/active_resource/base.rb, line 1149
    def destroy
      connection.delete(element_path, self.class.headers)
    end

dup() click to toggle source

Duplicates the current resource without saving it.

#### Examples

    my_invoice = Invoice.create(:customer => 'That Company')
    next_invoice = my_invoice.dup
    next_invoice.new? # => true

    next_invoice.save
    next_invoice == my_invoice # => false (different id attributes)

    my_invoice.customer   # => That Company
    next_invoice.customer # => That Company

    # File lib/active_resource/base.rb, line 1096
    def dup
      self.class.new.tap do |resource|
        resource.attributes     = @attributes
        resource.prefix_options = @prefix_options
      end
    end

encode(options={}) click to toggle source

Returns the serialized string representation of the resource in the configured serialization format specified in ActiveResource::Base.format. The options applicable depend on the configured encoding format.

    # File lib/active_resource/base.rb, line 1176
    def encode(options={})
      send("to_#{self.class.format.extension}", options)
    end

eql?(other) click to toggle source

Tests for equality (delegates to ==).

    # File lib/active_resource/base.rb, line 1074
    def eql?(other)
      self == other
    end

exists?() click to toggle source

Evaluates to `true` if this resource is not `new?` and is found on the remote service. Using this method, you can check for resources that may have been deleted between the object’s instantiation and actions on it.

#### Examples

    Person.create(:name => 'Theodore Roosevelt')
    that_guy = Person.find(:first)
    that_guy.exists? # => true

    that_lady = Person.new(:name => 'Paul Bean')
    that_lady.exists? # => false

    guys_id = that_guy.id
    Person.delete(guys_id)
    that_guy.exists? # => false

    # File lib/active_resource/base.rb, line 1169
    def exists?
      !new? && self.class.exists?(to_param, :params => prefix_options)
    end

hash() click to toggle source

Delegates to id in order to allow two resources of the same type and id to work with something like:

    [Person.find(1), Person.find(2)] & [Person.find(1), Person.find(4)] # => [Person.find(1)]

    # File lib/active_resource/base.rb, line 1080
    def hash
      id.hash
    end

id() click to toggle source

Gets the `\id` attribute of the resource.

    # File lib/active_resource/base.rb, line 1038
    def id
      attributes[self.class.primary_key]
    end

id=(id) click to toggle source

Sets the `\id` attribute of the resource.

    # File lib/active_resource/base.rb, line 1043
    def id=(id)
      attributes[self.class.primary_key] = id
    end

known_attributes() click to toggle source

This is a list of known attributes for this resource. Either gathered from the provided `schema`, or from the attributes set on this instance after it has been fetched from the remote system.

    # File lib/active_resource/base.rb, line 946
    def known_attributes
      self.class.known_attributes + self.attributes.keys.map(&:to_s)
    end

load(attributes) click to toggle source

A method to manually load attributes from a hash. Recursively loads collections of resources. This method is called in `initialize` and `create` when a hash of attributes is provided.

#### Examples

    my_attrs = {:name => 'J&J Textiles', :industry => 'Cloth and textiles'}
    my_attrs = {:name => 'Marty', :colors => ["red", "green", "blue"]}

    the_supplier = Supplier.find(:first)
    the_supplier.name # => 'J&M Textiles'
    the_supplier.load(my_attrs)
    the_supplier.name('J&J Textiles')

    # These two calls are the same as Supplier.new(my_attrs)
    my_supplier = Supplier.new
    my_supplier.load(my_attrs)

    # These three calls are the same as Supplier.create(my_attrs)
    your_supplier = Supplier.new
    your_supplier.load(my_attrs)
    your_supplier.save

    # File lib/active_resource/base.rb, line 1216
    def load(attributes)
      raise ArgumentError, "expected an attributes Hash, got #{attributes.inspect}" unless attributes.is_a?(Hash)
      @prefix_options, attributes = split_options(attributes)
      attributes.each do |key, value|
        @attributes[key.to_s] =
          case value
            when Array
              resource = find_or_create_resource_for_collection(key)
              value.map do |attrs|
                if attrs.is_a?(Hash)
                  resource.new(attrs)
                else
                  attrs.duplicable? ? attrs.dup : attrs
                end
              end
            when Hash
              resource = find_or_create_resource_for(key)
              resource.new(value)
            else
              value.dup rescue value
          end
      end
      self
    end

new?() click to toggle source

Returns `true` if this object hasn’t yet been saved, otherwise, returns `false`.

#### Examples

    not_new = Computer.create(:brand => 'Apple', :make => 'MacBook', :vendor => 'MacMall')
    not_new.new? # => false

    is_new = Computer.new(:brand => 'IBM', :make => 'Thinkpad', :vendor => 'IBM')
    is_new.new? # => true

    is_new.save
    is_new.new? # => false

    # File lib/active_resource/base.rb, line 1016
    def new?
      id.nil?
    end

Also aliased as: new_record?
new_record?() click to toggle source
Alias for: new?
persisted?() click to toggle source

Returns `true` if this object has been saved, otherwise returns `false`.

#### Examples

    persisted = Computer.create(:brand => 'Apple', :make => 'MacBook', :vendor => 'MacMall')
    persisted.persisted? # => true

    not_persisted = Computer.new(:brand => 'IBM', :make => 'Thinkpad', :vendor => 'IBM')
    not_persisted.persisted? # => false

    not_persisted.save
    not_persisted.persisted? # => true

    # File lib/active_resource/base.rb, line 1033
    def persisted?
      !new?
    end

reload() click to toggle source

A method to reload the attributes of this object from the remote web service.

#### Examples

    my_branch = Branch.find(:first)
    my_branch.name # => "Wislon Raod"

    # Another client fixes the typo...

    my_branch.name # => "Wislon Raod"
    my_branch.reload
    my_branch.name # => "Wilson Road"

    # File lib/active_resource/base.rb, line 1191
    def reload
      self.load(self.class.find(to_param, :params => @prefix_options).attributes)
    end

respond_to?(method, include_priv = false) click to toggle source

A method to determine if an object responds to a message (e.g., a method call). In Active Resource, a Person object with a `name` attribute can answer `true` to `my_person.respond_to?(:name)`, `my_person.respond_to?(:name=)`, and `my_person.respond_to?(:name?)`.

    # File lib/active_resource/base.rb, line 1277
    def respond_to?(method, include_priv = false)
      method_name = method.to_s
      if attributes.nil?
        super
      elsif known_attributes.include?(method_name)
        true
      elsif method_name =~ /(?:=|\?)$/ && attributes.include?($`)
        true
      else
        # super must be called at the end of the method, because the inherited respond_to?
        # would return true for generated readers, even if the attribute wasn't present
        super
      end
    end

Also aliased as: respond_to_without_attributes?
respond_to_without_attributes?(method, include_priv = false) click to toggle source

For checking `respond_to?` without searching the attributes (which is faster).

Alias for: respond_to?
save() click to toggle source

Saves (`POST`) or updates (`PUT`) a resource. Delegates to `create` if the object is new, `update` if it exists. If the response to the save includes a body, it will be assumed that this body is XML for the final object as it looked after the save (which would include attributes like `created_at` that weren’t part of the original submit).

#### Examples

    my_company = Company.new(:name => 'RoleModel Software', :owner => 'Ken Auer', :size => 2)
    my_company.new? # => true
    my_company.save # sends POST /companies/ (create)

    my_company.new? # => false
    my_company.size = 10
    my_company.save # sends PUT /companies/1 (update)

    # File lib/active_resource/base.rb, line 1116
    def save
      new? ? create : update
    end

save!() click to toggle source

Saves the resource.

If the resource is new, it is created via `POST`, otherwise the existing resource is updated via `PUT`.

With `save!` validations always run. If any of them fail ActiveResource::ResourceInvalid gets raised, and nothing is POSTed to the remote system. See ActiveResource::Validations for more information.

There’s a series of callbacks associated with `save!`. If any of the `before_*` callbacks return `false` the action is cancelled and `save!` raises ActiveResource::ResourceInvalid.

    # File lib/active_resource/base.rb, line 1133
    def save!
      save || raise(ResourceInvalid.new(self))
    end

schema() click to toggle source

If no schema has been defined for the class (see `ActiveResource::schema=`), the default automatic schema is generated from the current instance’s attributes

    # File lib/active_resource/base.rb, line 939
    def schema
      self.class.schema || self.attributes
    end

to_json(options={}) click to toggle source

    # File lib/active_resource/base.rb, line 1292
    def to_json(options={})
      super({ :root => self.class.element_name }.merge(options))
    end

to_xml(options={}) click to toggle source

    # File lib/active_resource/base.rb, line 1296
    def to_xml(options={})
      super({ :root => self.class.element_name }.merge(options))
    end

update_attribute(name, value) click to toggle source

Updates a single attribute and then saves the object.

Note: Unlike ActiveRecord::Base.update_attribute, this method is subject to normal validation routines as an update sends the whole body of the resource in the request. (See Validations).

As such, this method is equivalent to calling update_attributes with a single attribute/value pair.

If the saving fails because of a connection or remote service error, an exception will be raised. If saving fails because the resource is invalid then `false` will be returned.

    # File lib/active_resource/base.rb, line 1252
    def update_attribute(name, value)
      self.send("#{name}=".to_sym, value)
      self.save
    end

update_attributes(attributes) click to toggle source

Updates this resource with all the attributes from the passed-in Hash and requests that the record be saved.

If the saving fails because of a connection or remote service error, an exception will be raised. If saving fails because the resource is invalid then `false` will be returned.

Note: Though this request can be made with a partial set of the resource’s attributes, the full body of the request will still be sent in the save request to the remote service.

    # File lib/active_resource/base.rb, line 1267
    def update_attributes(attributes)
      load(attributes) && save
    end

### Protected Instance Methods

collection_path(options = nil) click to toggle source

    # File lib/active_resource/base.rb, line 1339
    def collection_path(options = nil)
      self.class.collection_path(options || prefix_options)
    end

connection(refresh = false) click to toggle source

    # File lib/active_resource/base.rb, line 1301
    def connection(refresh = false)
      self.class.connection(refresh)
    end

create() click to toggle source

Create (i.e., save to the remote service) the new resource.

    # File lib/active_resource/base.rb, line 1313
    def create
      connection.post(collection_path, encode, self.class.headers).tap do |response|
        self.id = id_from_response(response)
        load_attributes_from_response(response)
      end
    end

element_path(options = nil) click to toggle source

    # File lib/active_resource/base.rb, line 1331
    def element_path(options = nil)
      self.class.element_path(to_param, options || prefix_options)
    end

id_from_response(response) click to toggle source

Takes a response from a typical create post and pulls the ID out

    # File lib/active_resource/base.rb, line 1327
    def id_from_response(response)
      response['Location'][/\/([^\/]*?)(\.\w+)?$/, 1] if response['Location']
    end

load_attributes_from_response(response) click to toggle source

    # File lib/active_resource/base.rb, line 1320
    def load_attributes_from_response(response)
      if response['Content-Length'] != "0" && response.body.strip.size > 0
        load(self.class.format.decode(response.body))
      end
    end

new_element_path() click to toggle source

    # File lib/active_resource/base.rb, line 1335
    def new_element_path
      self.class.new_element_path(prefix_options)
    end

update() click to toggle source

Update the resource on the remote service.

    # File lib/active_resource/base.rb, line 1306
    def update
      connection.put(element_path(prefix_options), encode, self.class.headers).tap do |response|
        load_attributes_from_response(response)
      end
    end

[Validate]

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