Added client.data_source to receive meta information about a source

lib/druid/client.rb

@@ -45,5 +45,28 @@ def data_source_uri(source)
       return URI(uri) if uri
       nil
     end
+
+    def data_source(source)
+      uri = data_source_uri(source)
+      raise "data source #{id} (currently) not available" unless uri
+
+      meta_path = "#{uri.path}datasources/#{source.split('/').last}"
+
+      req = Net::HTTP::Get.new(meta_path)
+
+      response = Net::HTTP.new(uri.host, uri.port).start do |http| 
+        http.read_timeout = (2 * 60 * 1000)
+        http.request(req)
+      end
+
+      if response.code == "200"
+        meta = JSON.parse(response.body)
+        meta.define_singleton_method(:dimensions) { self['dimensions'] }
+        meta.define_singleton_method(:metrics) { self['metrics'] }
+        meta
+      else
+        raise "Request failed: #{response.code}: #{response.body}"
+      end
+    end
   end
 end

spec/lib/client_spec.rb

@@ -48,4 +48,22 @@
 		client.data_source_uri('madvertise/mock').should == URI('mock_uri')
 	end
 
+	it 'should report dimensions of a data source correctly' do
+		stub_request(:get, "http://www.example.com/druid/v2/datasources/mock").
+		  with(:headers =>{'Accept'=>'*/*', 'User-Agent'=>'Ruby'}).
+			to_return(:status => 200, :body => '{"dimensions":["d1","d2","d3"],"metrics":["m1", "m2"]}')
+
+		client = Druid::Client.new('test_uri', :static_setup => {'madvertise/mock' => 'http://www.example.com/druid/v2/'})
+		client.data_source('madvertise/mock').dimensions.should == ["d1","d2","d3"]
+	end
+
+	it 'should report metrics of a data source correctly' do
+		stub_request(:get, "http://www.example.com/druid/v2/datasources/mock").
+		  with(:headers =>{'Accept'=>'*/*', 'User-Agent'=>'Ruby'}).
+			to_return(:status => 200, :body => '{"dimensions":["d1","d2","d3"],"metrics":["m1", "m2"]}')
+
+		client = Druid::Client.new('test_uri', :static_setup => {'madvertise/mock' => 'http://www.example.com/druid/v2/'})
+		client.data_source('madvertise/mock').metrics.should == ["m1","m2"]
+	end
+
 end