Adding manual view support to uniqueness validation

README.md

@@ -222,9 +222,15 @@ CouchRest Model adds the possibility to check the uniqueness of attributes using
       validates_uniqueness_of :title
     end
 
-The uniqueness validation creates a new view for the attribute or uses one that already exists.
+The uniqueness validation creates a new view for the attribute or uses one that already exists. You can
+specify a different view using the +:view+ option, useful for when the @unique_id@ is specified and
+you'd like to avoid the typical RestClient Conflict error:
+
+    unique_id :code
+    validates_uniqueness_of :code, :view => 'all'
+
 Given that the uniqueness check performs a request to the database, it is also possible
-to include a +:proxy+ parameter. This allows you to
+to include a @:proxy@ parameter. This allows you to
 call a method on the document and provide an alternate proxy object.
 
 Examples:

lib/couchrest/model/validations.rb

@@ -40,10 +40,17 @@ module CouchRest
         #     validates_uniqueness_of :title
         #   end
         #
-        # Asside from the standard options, a +:proxy+ parameter is also accepted if you would 
+        # Asside from the standard options, you can specify the name of the view you'd like
+        # to use for the search inside the +:view+ option. The following example would search
+        # for the code in side the +all+ view, useful for when +unique_id+ is used and you'd
+        # like to check before receiving a RestClient Conflict error:
+        #
+        #   validates_uniqueness_of :code, :view => 'all'
+        #
+        # A +:proxy+ parameter is also accepted if you would 
         # like to call a method on the document on which the view should be performed.
         #
-        # Examples:
+        # For Example:
         #
         #   # Same as not including proxy:
         #   validates_uniqueness_of :title, :proxy => 'class'

lib/couchrest/model/validations/uniqueness.rb

@@ -15,14 +15,17 @@ module CouchRest
 
 
         def validate_each(document, attribute, value)
-          unless @klass.has_view?("by_#{attribute}")
+          view_name = options[:view].nil? ? "by_#{attribute}" : options[:view]
+
+          unless @klass.has_view?(view_name)
+            raise "View #{document.class.name}.#{options[:view]} does not exist!" unless options[:view].nil?
             @klass.view_by attribute
           end
 
           # Determine the base of the search
           base = options[:proxy].nil? ? @klass : document.instance_eval(options[:proxy])
 
-          docs = base.view("by_#{attribute}", :key => value, :limit => 2, :include_docs => false)['rows']
+          docs = base.view(view_name, :key => value, :limit => 2, :include_docs => false)['rows']
           return if docs.empty?
 
           unless document.new?

spec/couchrest/validations.rb

@@ -34,8 +34,23 @@ describe "Validations" do
       @obj.should be_valid
     end
 
+    it "should allow own view to be specified" do
+      # validates_uniqueness_of :code, :view => 'all'
+      WithUniqueValidationView.create(:title => 'title 1', :code => '1234')
+      @obj = WithUniqueValidationView.new(:title => 'title 5', :code => '1234')
+      @obj.should_not be_valid
+    end
+
+    it "should raise an error if specified view does not exist" do
+      WithUniqueValidationView.validates_uniqueness_of :title, :view => 'fooobar'
+      @obj = WithUniqueValidationView.new(:title => 'title 2', :code => '12345')
+      lambda {
+        @obj.valid?
+      }.should raise_error
+    end
+
     context "with a pre-defined view" do
-      it "should no try to create new view" do
+      it "should not try to create new view" do
         @obj = @objs[1]
         @obj.class.should_not_receive('view_by')
         @obj.class.should_receive('has_view?').and_return(true)
@@ -46,9 +61,8 @@ describe "Validations" do
  
     context "with a proxy parameter" do
       it "should be used" do
-        @obj = @objs.first
+        @obj = WithUniqueValidationProxy.new(:title => 'test 6')
         proxy = @obj.should_receive('proxy').and_return(@obj.class)
-        @obj.class.validates_uniqueness_of :title, :proxy => 'proxy'
         @obj.valid?.should be_true
       end
     end

spec/fixtures/base.rb

@@ -116,10 +116,24 @@ end
 
 class WithUniqueValidation < CouchRest::Model::Base
   use_database DB
-
+  property :title
+  validates_uniqueness_of :title
+end
+class WithUniqueValidationProxy < CouchRest::Model::Base
+  use_database DB
+  property :title
+  validates_uniqueness_of :title, :proxy => 'proxy'
+end
+class WithUniqueValidationView < CouchRest::Model::Base
+  use_database DB
+  attr_accessor :code
+  unique_id :code
+  def code
+    self["_id"] ||= @code
+  end
   property :title
 
-  validates_uniqueness_of :title
+  validates_uniqueness_of :code, :view => 'all'
 end