Add raise InvalidPrimaryKey

- Use auto_increment_id of PrimaryKey == 0 in MySQL, not use sequencer id

lib/active_record/sharding/errors.rb

@@ -11,5 +11,8 @@ class MissingPrimaryKey < Error
 
     class InvalidSequenceId < Error
     end
+
+    class InvalidPrimaryKey < Error
+    end
   end
 end

lib/active_record/sharding/model.rb

@@ -73,6 +73,7 @@ def define_parent_methods(&block)
 
         def validate_id!
           raise ActiveRecord::Sharding::MissingPrimaryKey if attributes[self.class.primary_key].nil?
+          raise ActiveRecord::Sharding::InvalidPrimaryKey if attributes[self.class.primary_key].zero?
         end
     end
   end

spec/active_record/sharding/model_spec.rb

@@ -42,6 +42,10 @@ def find_from_all_by_name(name)
       expect(alice.class.name).to match(/User::ShardFor/)
     end
 
+    it "raise InvalidPrimaryKey" do
+      expect { model.put! id: 0, name: "invalid_id" }.to raise_error ActiveRecord::Sharding::InvalidPrimaryKey
+    end
+
     context "in transaction" do
       it "when rollback" do
         before_record_count = model.all_shards.map(&:count).reduce(:+)