working on proxy association and handling

lib/couchrest/model/associations.rb

@@ -11,23 +11,33 @@ module CouchRest
       module ClassMethods
 
         # Define an association that this object belongs to.
-        # 
+        #
+        # An attribute will be created matching the name of the attribute
+        # with '_id' on the end, or the foreign key (:foreign_key) provided.
+        #
+        # Searching for the assocated object is performed using a string 
+        # (:proxy) to be evaulated in the context of the owner. Typically
+        # this will be set to the class name (:class_name), or determined
+        # automatically if the owner belongs to a proxy object.
+        #
+        # If the association owner is proxied by another model, than an attempt will
+        # be made to automatically determine the correct place to request
+        # the documents. Typically, this is a method with the pluralized name of the 
+        # association inside owner's owner, or proxy.
+        #
+        # For example, imagine a company acts as a proxy for invoices and clients.
+        # If an invoice belongs to a client, the invoice will need to access the
+        # list of clients via the proxy. So a request to search for the associated
+        # client from an invoice would look like:
+        #
+        #    self.company.clients
+        #
+        # If the name of the collection proxy is not the pluralized assocation name, 
+        # it can be set with the :proxy_name option.
+        #
         def belongs_to(attrib, *options)
-          opts = {
-            :foreign_key => attrib.to_s + '_id',
-            :class_name => attrib.to_s.camelcase,
-            :proxy => nil
-          }
-          case options.first
-          when Hash
-            opts.merge!(options.first)
-          end
 
-          begin
+          opts = merge_belongs_to_assocation_options(attrib, options.first)
-            opts[:class] = opts[:class_name].constantize
-          rescue NameError
-            raise NameError, "Unable to convert class name into Constant for #{self.name}##{attrib}"
-          end
 
           prop = property(opts[:foreign_key], opts)
 
@@ -77,20 +87,9 @@ module CouchRest
         # frequently! Use with prudence.
         #
         def collection_of(attrib, *options)
-          opts = {
+
-            :foreign_key => attrib.to_s.singularize + '_ids',
+          opts = merge_belongs_to_assocation_options(attrib, options.first)
-            :class_name => attrib.to_s.singularize.camelcase,
+          opts[:foreign_key] = opts[:foreign_key].pluralize
-            :proxy => nil
-          }
-          case options.first
-          when Hash
-            opts.merge!(options.first)
-          end
-          begin
-            opts[:class] = opts[:class_name].constantize
-          rescue
-            raise "Unable to convert class name into Constant for #{self.name}##{attrib}"
-          end
           opts[:readonly] = true
 
           prop = property(opts[:foreign_key], [], opts)
@@ -105,11 +104,42 @@ module CouchRest
 
         private
 
+        def merge_belongs_to_assocation_options(attrib, options = nil)
+          opts = {
+            :foreign_key => attrib.to_s + '_id',
+            :class_name => attrib.to_s.camelcase,
+            :proxy_name => attrib.to_s.pluralize
+          }
+
+          # merge the options
+          case options
+          when Hash
+            opts.merge!(options)
+          end
+          # Get a class name
+          begin
+            opts[:class] = opts[:class_name].constantize
+          rescue NameError
+            raise NameError, "Unable to convert class name into Constant for #{self.name}##{attrib}"
+          end
+
+          # Generate a string for the proxy method call
+          # Assumes that the proxy_owner_method from "proxyable" is available.
+          if opts[:proxy].to_s.empty?
+            opts[:proxy] = if proxy_owner_method
+              "self.#{proxy_owner_method}.#{opts[:proxy_name]}"
+            else
+              opts[:class_name].constantize
+            end
+          end
+
+          opts
+        end
+
         def create_belongs_to_getter(attrib, property, options)
-          base = options[:proxy] || options[:class_name]
           class_eval <<-EOS, __FILE__, __LINE__ + 1
             def #{attrib}
-              @#{attrib} ||= #{options[:foreign_key]}.nil? ? nil : (model_proxy || #{base}).get(self.#{options[:foreign_key]})
+              @#{attrib} ||= #{options[:foreign_key]}.nil? ? nil : #{options[:proxy]}.get(self.#{options[:foreign_key]})
             end
           EOS
         end
@@ -140,7 +170,7 @@ module CouchRest
           class_eval <<-EOS, __FILE__, __LINE__ + 1
             def #{attrib}(reload = false)
               return @#{attrib} unless @#{attrib}.nil? or reload
-              ary = self.#{options[:foreign_key]}.collect{|i| (model_proxy || #{base}).get(i)}
+              ary = self.#{options[:foreign_key]}.collect{|i| #{base}.get(i)}
               @#{attrib} = ::CouchRest::CollectionOfProxy.new(ary, self, '#{options[:foreign_key]}')
             end
           EOS

lib/couchrest/model/casted_model.rb

@@ -54,13 +54,6 @@ module CouchRest::Model
     alias :to_key :id
     alias :to_param :id
 
-    # Fixes belongs_to assocations. 
-    # See it "should allow to reference association by id in casted model" in 
-    # assocations_spec.rb
-    def model_proxy 
-      nil
-    end
-    
     # Sets the attributes from a hash
     def update_attributes_without_saving(hash)
       hash.each do |k, v|

lib/couchrest/model/proxyable.rb

@@ -4,29 +4,29 @@ module CouchRest
     module Proxyable
       extend ActiveSupport::Concern
 
-      included do
-        attr_accessor :model_proxy
-      end
-
       module ClassMethods
 
+        attr_reader :proxy_owner_method
+
         # Define a collection that will use the base model for the database connection
         # details.
-        def proxy_for(model_name, options = {})
+        def proxy_for(assoc_name, options = {})
           db_method = options[:database_method] || "proxy_database"
-          options[:class_name] ||= model_name.to_s.singularize.camelize
+          options[:class_name] ||= assoc_name.to_s.singularize.camelize
+          attr_accessor :model_proxy
           class_eval <<-EOS, __FILE__, __LINE__ + 1
-            def #{model_name}
+            def #{assoc_name}
               unless respond_to?('#{db_method}')
                 raise "Missing ##{db_method} method for proxy"
               end
-              @#{model_name} ||= CouchRest::Model::Proxyable::ModelProxy.new(::#{options[:class_name]}, self, self.class.to_s.underscore, #{db_method})
+              @#{assoc_name} ||= CouchRest::Model::Proxyable::ModelProxy.new(::#{options[:class_name]}, self, self.class.to_s.underscore, #{db_method})
             end
           EOS
         end
 
         def proxied_by(model_name, options = {})
-          raise "Model can only be proxied once or ##{model_name} already defined" if method_defined?(model_name)
+          raise "Model can only be proxied once or ##{model_name} already defined" if method_defined?(model_name) || !proxy_owner_method.nil?
+          self.proxy_owner_method = model_name
           attr_accessor model_name
         end
       end
@@ -134,7 +134,7 @@ module CouchRest
         def proxy_update(doc)
           if doc
             doc.database = @database if doc.respond_to?(:database=)
-            doc.model_proxy = self if doc.respond_to?(:model_proxy=) 
+            doc.model_proxy = self if doc.respond_to?(:model_proxy=)
             doc.send("#{owner_name}=", owner) if doc.respond_to?("#{owner_name}=")
           end
           doc

lib/couchrest/model/validations/uniqueness.rb

@@ -15,7 +15,8 @@ module CouchRest
 
         def validate_each(document, attribute, value)
           view_name = options[:view].nil? ? "by_#{attribute}" : options[:view]
-          model = document.model_proxy || @model
+
+          model = (respond_to?(:model_proxy) && model_proxy ? model_proxy : @model)
           # Determine the base of the search
           base = options[:proxy].nil? ? model : document.instance_eval(options[:proxy])
 
@@ -30,7 +31,7 @@ module CouchRest
           unless document.new?
             return if docs.find{|doc| doc['id'] == document.id}
           end
-          
+
           if docs.length > 0
             document.errors.add(attribute, :taken, options.merge(:value => value))
           end

spec/couchrest/assocations_spec.rb

@@ -64,22 +64,6 @@ describe "Assocations" do
       @invoice.alternate_client.id.should eql(@client.id)
     end
 
-    it "should allow to reference association by id in casted model" do
-      class Money < Hash
-        include CouchRest::Model::CastedModel
-
-        property :value, Integer
-        belongs_to :client
-      end
-
-      money = Money.new :value => 1000
-
-      money.client_id = @client.id
-
-      money.client.should eql(@client)
-      money.valid?.should be_true
-    end
-
   end
 
   describe "of type collection_of" do