tracks/vendor/rails/activeresource/lib/active_resource/base.rb
Luke Melia 901a58f8a3 Upgraded to Rails 2.1. This can have wide ranging consequences, so please help track down any issues introduced by the upgrade. Requires environment.rb modifications.
Changes you will need to make:

 * In your environment.rb, you will need to update references to a few files per environment.rb.tmpl
 * In your environment.rb, you will need to specify the local time zone of the computer that is running your Tracks install.

Other notes on my changes:

 * Modified our code to take advantage of Rails 2.1's slick time zone support.
 * Upgraded will_paginate for compatibility
 * Hacked the Selenium on Rails plugin, which has not been updated in some time and does not support Rails 2.1
 * Verified that all tests pass on my machine, including Selenium tests -- I'd like confirmation from others, too.
2008-06-17 01:13:25 -04:00

1014 lines
38 KiB
Ruby

require 'active_resource/connection'
require 'cgi'
require 'set'
module ActiveResource
# 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 link:files/vendor/rails/activeresource/README.html.
#
# == 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 <tt>http://api.people.com:3000/people/</tt>, and
# you can now use Active Resource's lifecycles 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
#
#
# == Lifecycle 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 lifecycle methods for database records.
# You can read more about each of these methods in their respective documentation.
#
# === Custom REST methods
#
# Since simple CRUD/lifecycle methods can't accomplish every task, Active Resource also supports
# defining your own custom REST methods. To invoke them, Active Resource provides the <tt>get</tt>,
# <tt>post</tt>, <tt>put</tt> and <tt>delete</tt> 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:
# * 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 seperate user and password option.
# == 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 <tt>404</tt> (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
#
# <tt>404</tt> 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
# * 404 - ActiveResource::ResourceNotFound
# * 409 - ActiveResource::ResourceConflict
# * 422 - ActiveResource::ResourceInvalid (rescued by save as validation errors)
# * 401..499 - ActiveResource::ClientError
# * 500..599 - ActiveResource::ServerError
#
# 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 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 <tt>422</tt> and an XML representation of the validation errors. The save operation will
# then fail (with a <tt>false</tt> 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
# # is requested with invalid values, the response is:
# #
# # Response (422):
# # <errors type="array"><error>First cannot be empty</error></errors>
# #
#
# 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
# http://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 <tt>read_timeout</tt> of the internal Net::HTTP instance to the same value. The default
# <tt>read_timeout</tt> is 60 seconds on most Ruby implementations.
class Base
# The logger for diagnosing and tracing Active Resource calls.
cattr_accessor :logger
class << self
# Gets the URI of the REST resources to map for this class. The site variable is required
# Active Resource's mapping to work.
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
# Sets the URI of the REST resources to map for this class to the value in the +site+ argument.
# The site variable is required Active Resource's mapping to work.
def site=(site)
@connection = nil
if site.nil?
@site = nil
else
@site = create_site_uri_from(site)
@user = URI.decode(@site.user) if @site.user
@password = URI.decode(@site.password) if @site.password
end
end
# Gets the user for REST HTTP authentication.
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
# Sets the user for REST HTTP authentication.
def user=(user)
@connection = nil
@user = user
end
# Gets the password for REST HTTP authentication.
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
# Sets the password for REST HTTP authentication.
def password=(password)
@connection = nil
@password = password
end
# 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 <tt>:xml</tt>.
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
# Returns the current format, default is ActiveResource::Formats::XmlFormat.
def format # :nodoc:
read_inheritable_attribute("format") || ActiveResource::Formats[:xml]
end
# Sets the number of seconds after which requests to the REST API should time out.
def timeout=(timeout)
@connection = nil
@timeout = timeout
end
# Gets tthe number of seconds after which requests to the REST API should time out.
def timeout
if defined?(@timeout)
@timeout
elsif superclass != Object && superclass.timeout
superclass.timeout
end
end
# 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 <tt>false</tt>).
def connection(refresh = false)
if defined?(@connection) || superclass == Object
@connection = Connection.new(site, format) if refresh || @connection.nil?
@connection.user = user if user
@connection.password = password if password
@connection.timeout = timeout if timeout
@connection
else
superclass.connection
end
end
def headers
@headers ||= {}
end
# Do not include any modules in the default element name. This makes it easier to seclude ARes objects
# in a separate namespace without having to set element_name repeatedly.
attr_accessor_with_default(:element_name) { to_s.split("::").last.underscore } #:nodoc:
attr_accessor_with_default(:collection_name) { element_name.pluralize } #:nodoc:
attr_accessor_with_default(:primary_key, 'id') #:nodoc:
# Gets the prefix for a resource's nested URL (e.g., <tt>prefix/collectionname/1.xml</tt>)
# This method is regenerated at runtime based on what the prefix is set to.
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
# 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.
def prefix_source
prefix # generate #prefix and #prefix_source methods first
prefix_source
end
# Sets the prefix for a resource's nested URL (e.g., <tt>prefix/collectionname/1.xml</tt>).
# Default value is <tt>site.path</tt>.
def prefix=(value = '/')
# Replace :placeholders with '#{embedded options[:lookups]}'
prefix_call = value.gsub(/:\w+/) { |key| "\#{options[#{key}]}" }
# Redefine the new methods.
code = <<-end_code
def prefix_source() "#{value}" end
def prefix(options={}) "#{prefix_call}" end
end_code
silence_warnings { instance_eval code, __FILE__, __LINE__ }
rescue
logger.error "Couldn't set prefix: #{$!}\n #{code}"
raise
end
alias_method :set_prefix, :prefix= #:nodoc:
alias_method :set_element_name, :element_name= #:nodoc:
alias_method :set_collection_name, :collection_name= #:nodoc:
# 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., <tt>:account_id => 19</tt>
# 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
#
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}/#{id}.#{format.extension}#{query_string(query_options)}"
end
# 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 URL's (e.g., <tt>:account_id => 19</tt>
# 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.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
#
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
alias_method :set_primary_key, :primary_key= #:nodoc:
# Create a new resource instance and request to the remote service
# that it be saved, making it equivalent to the following simultaneous calls:
#
# ryan = Person.new(:first => 'ryan')
# ryan.save
#
# The newly created resource is returned. 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 <tt>false</tt>,
# while new? will still return <tt>true</tt>.
#
# ==== 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
def create(attributes = {})
returning(self.new(attributes)) { |res| res.save }
end
# 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.
#
# * <tt>:one</tt> - Returns a single resource.
# * <tt>:first</tt> - Returns the first resource found.
# * <tt>:all</tt> - Returns every resource that matches the request.
#
# ==== Options
#
# * <tt>:from</tt> - Sets the path or custom method that resources will be fetched from.
# * <tt>:params</tt> - 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(: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
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 :one then find_one(options)
else find_single(scope, options)
end
end
# 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
def delete(id, options = {})
connection.delete(element_path(id, options))
end
# Asserts the existence of a resource, returning <tt>true</tt> if the resource is found.
#
# ==== Examples
# Note.create(:title => 'Hello, world.', :body => 'Nothing more for now...')
# Note.exists?(1) # => true
#
# Note.exists(1349) # => false
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 == 200
end
# id && !find_single(id, options).nil?
rescue ActiveResource::ResourceNotFound
false
end
private
# Find every resource
def find_every(options)
case from = options[:from]
when Symbol
instantiate_collection(get(from, options[:params]))
when String
path = "#{from}#{query_string(options[:params])}"
instantiate_collection(connection.get(path, headers) || [])
else
prefix_options, query_options = split_options(options[:params])
path = collection_path(prefix_options, query_options)
instantiate_collection( (connection.get(path, headers) || []), prefix_options )
end
end
# Find a single resource from a one-off URL
def find_one(options)
case from = options[:from]
when Symbol
instantiate_record(get(from, options[:params]))
when String
path = "#{from}#{query_string(options[:params])}"
instantiate_record(connection.get(path, headers))
end
end
# Find a single resource from the default URL
def find_single(scope, options)
prefix_options, query_options = split_options(options[:params])
path = element_path(scope, prefix_options, query_options)
instantiate_record(connection.get(path, headers), prefix_options)
end
def instantiate_collection(collection, prefix_options = {})
collection.collect! { |record| instantiate_record(record, prefix_options) }
end
def instantiate_record(record, prefix_options = {})
returning new(record) do |resource|
resource.prefix_options = prefix_options
end
end
# Accepts a URI and creates the site URI from that.
def create_site_uri_from(site)
site.is_a?(URI) ? site.dup : URI.parse(site)
end
# contains a set of the current prefix parameters.
def prefix_parameters
@prefix_parameters ||= prefix_source.scan(/:\w+/).map { |key| key[1..-1].to_sym }.to_set
end
# Builds the query string for the request.
def query_string(options)
"?#{options.to_query}" unless options.nil? || options.empty?
end
# split an option hash into two hashes, one containing the prefix options,
# and the other containing the leftovers.
def split_options(options = {})
prefix_options, query_options = {}, {}
(options || {}).each do |key, value|
next if key.blank?
(prefix_parameters.include?(key.to_sym) ? prefix_options : query_options)[key.to_sym] = value
end
[ prefix_options, query_options ]
end
end
attr_accessor :attributes #:nodoc:
attr_accessor :prefix_options #:nodoc:
# 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
def initialize(attributes = {})
@attributes = {}
@prefix_options = {}
load(attributes)
end
# 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"}
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
# A method to determine if the resource a new object (i.e., it has not been POSTed to the remote service yet).
#
# ==== 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
#
def new?
id.nil?
end
# Get the +id+ attribute of the resource.
def id
attributes[self.class.primary_key]
end
# Set the +id+ attribute of the resource.
def id=(id)
attributes[self.class.primary_key] = id
end
# Allows Active Resource objects to be used as parameters in Action Pack URL generation.
def to_param
id && id.to_s
end
# 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 <tt>new?</tt>, 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
#
def ==(other)
other.equal?(self) || (other.instance_of?(self.class) && !other.new? && other.id == id)
end
# Tests for equality (delegates to ==).
def eql?(other)
self == other
end
# 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)]
def hash
id.hash
end
# Duplicate 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
def dup
returning self.class.new do |resource|
resource.attributes = @attributes
resource.prefix_options = @prefix_options
end
end
# A method to save (+POST+) or update (+PUT+) a resource. It delegates to +create+ if a new object,
# +update+ if it is existing. 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)
def save
new? ? create : update
end
# 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)
def destroy
connection.delete(element_path, self.class.headers)
end
# Evaluates to <tt>true</tt> if this resource is not <tt>new?</tt> 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
def exists?
!new? && self.class.exists?(to_param, :params => prefix_options)
end
# A method to convert the the resource to an XML string.
#
# ==== Options
# The +options+ parameter is handed off to the +to_xml+ method on each
# attribute, so it has the same options as the +to_xml+ methods in
# Active Support.
#
# * <tt>:indent</tt> - Set the indent level for the XML output (default is +2+).
# * <tt>:dasherize</tt> - Boolean option to determine whether or not element names should
# replace underscores with dashes (default is <tt>false</tt>).
# * <tt>:skip_instruct</tt> - Toggle skipping the +instruct!+ call on the XML builder
# that generates the XML declaration (default is <tt>false</tt>).
#
# ==== Examples
# my_group = SubsidiaryGroup.find(:first)
# my_group.to_xml
# # => <?xml version="1.0" encoding="UTF-8"?>
# # <subsidiary_group> [...] </subsidiary_group>
#
# my_group.to_xml(:dasherize => true)
# # => <?xml version="1.0" encoding="UTF-8"?>
# # <subsidiary-group> [...] </subsidiary-group>
#
# my_group.to_xml(:skip_instruct => true)
# # => <subsidiary_group> [...] </subsidiary_group>
def to_xml(options={})
attributes.to_xml({:root => self.class.element_name}.merge(options))
end
# 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"
def reload
self.load(self.class.find(to_param, :params => @prefix_options).attributes)
end
# 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'}
#
# 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
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 { |attrs| resource.new(attrs) }
when Hash
resource = find_or_create_resource_for(key)
resource.new(value)
else
value.dup rescue value
end
end
self
end
# For checking <tt>respond_to?</tt> without searching the attributes (which is faster).
alias_method :respond_to_without_attributes?, :respond_to?
# 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 <tt>true</tt> to <tt>my_person.respond_to?("name")</tt>, <tt>my_person.respond_to?("name=")</tt>, and
# <tt>my_person.respond_to?("name?")</tt>.
def respond_to?(method, include_priv = false)
method_name = method.to_s
if attributes.nil?
return super
elsif attributes.has_key?(method_name)
return true
elsif ['?','='].include?(method_name.last) && attributes.has_key?(method_name.first(-1))
return true
end
# 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
protected
def connection(refresh = false)
self.class.connection(refresh)
end
# Update the resource on the remote service.
def update
returning connection.put(element_path(prefix_options), to_xml, self.class.headers) do |response|
load_attributes_from_response(response)
end
end
# Create (i.e., save to the remote service) the new resource.
def create
returning connection.post(collection_path, to_xml, self.class.headers) do |response|
self.id = id_from_response(response)
load_attributes_from_response(response)
end
end
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
# Takes a response from a typical create post and pulls the ID out
def id_from_response(response)
response['Location'][/\/([^\/]*?)(\.\w+)?$/, 1]
end
def element_path(options = nil)
self.class.element_path(to_param, options || prefix_options)
end
def collection_path(options = nil)
self.class.collection_path(options || prefix_options)
end
private
# Tries to find a resource for a given collection name; if it fails, then the resource is created
def find_or_create_resource_for_collection(name)
find_or_create_resource_for(name.to_s.singularize)
end
# Tries to find a resource in a non empty list of nested modules
# Raises a NameError if it was not found in any of the given nested modules
def find_resource_in_modules(resource_name, module_names)
receiver = Object
namespaces = module_names[0, module_names.size-1].map do |module_name|
receiver = receiver.const_get(module_name)
end
if namespace = namespaces.reverse.detect { |ns| ns.const_defined?(resource_name) }
return namespace.const_get(resource_name)
else
raise NameError
end
end
# Tries to find a resource for a given name; if it fails, then the resource is created
def find_or_create_resource_for(name)
resource_name = name.to_s.camelize
ancestors = self.class.name.split("::")
if ancestors.size > 1
find_resource_in_modules(resource_name, ancestors)
else
self.class.const_get(resource_name)
end
rescue NameError
resource = self.class.const_set(resource_name, Class.new(ActiveResource::Base))
resource.prefix = self.class.prefix
resource.site = self.class.site
resource
end
def split_options(options = {})
self.class.send!(:split_options, options)
end
def method_missing(method_symbol, *arguments) #:nodoc:
method_name = method_symbol.to_s
case method_name.last
when "="
attributes[method_name.first(-1)] = arguments.first
when "?"
attributes[method_name.first(-1)]
else
attributes.has_key?(method_name) ? attributes[method_name] : super
end
end
end
end