nql in query interface

lib/rasti/db/collection.rb

@@ -2,7 +2,7 @@ module Rasti
   module DB
     class Collection
 
-      QUERY_METHODS = (Query::DATASET_CHAINED_METHODS + [:graph, :join, :count, :all, :each, :first, :pluck, :primary_keys, :any?, :empty?, :raw]).freeze
+      QUERY_METHODS = (Query::DATASET_CHAINED_METHODS + [:graph, :join, :count, :all, :each, :first, :pluck, :primary_keys, :any?, :empty?, :raw, :nql]).freeze
 
       include Enumerable
       include Helpers::WithSchema

lib/rasti/db/query.rb

@@ -92,6 +92,15 @@ def to_s
       end
       alias_method :inspect, :to_s
 
+      def nql(filter_expression)
+        sentence = nql_parser.parse filter_expression
+
+        dependency_tables = sentence.dependency_tables
+        query = dependency_tables.empty? ? self : join(*dependency_tables)
+
+        query.where sentence.filter_condition
+      end
+
       private
 
       def chainable(&block)
@@ -122,6 +131,10 @@ def respond_to_missing?(method, include_private=false)
         collection_class.queries.key?(method) || super
       end
 
+      def nql_parser
+        NQL::SyntaxParser.new
+      end
+
       attr_reader :collection_class, :dataset, :relations, :schema
 
     end

spec/query_spec.rb

@@ -177,4 +177,52 @@
 
   end
 
+  describe 'NQL' do
+
+    before do
+      1.upto(10) do |i| 
+        db[:people].insert user_id: i, 
+                           document_number: i, 
+                           first_name: "Name #{i}", 
+                           last_name: "Last Name #{i}", 
+                           birth_date: Time.now
+      end
+
+      1.upto(3) { |i| db[:categories].insert name: "Category #{i}" }
+
+      db[:comments].insert post_id: 1, user_id: 5, text: 'Comment 1'
+      db[:comments].insert post_id: 1, user_id: 7, text: 'Comment 2'
+      db[:comments].insert post_id: 2, user_id: 2, text: 'Comment 3'
+
+      db[:categories_posts].insert post_id: 1, category_id: 1
+      db[:categories_posts].insert post_id: 1, category_id: 2
+      db[:categories_posts].insert post_id: 2, category_id: 2
+      db[:categories_posts].insert post_id: 2, category_id: 3
+      db[:categories_posts].insert post_id: 3, category_id: 3
+    end
+
+    it 'Filter to self table' do
+      people_query = Rasti::DB::Query.new People, db[:people]
+
+      people_query.nql('user_id > 7')
+                  .map(&:user_id)
+                  .sort
+                  .must_equal [8, 9, 10]
+    end
+
+    it 'Filter to join table' do
+      posts_query.nql('categories.name = Category 2')
+                 .map(&:id)
+                 .sort
+                 .must_equal [1, 2]
+    end
+
+    it 'Filter to 2nd order relation' do
+      posts_query.nql('comments.user.person.document_number = 7')
+                 .map(&:id)
+                 .must_equal [1]
+    end
+
+  end
+
 end