Fixed msg index start from 0

Author: AndriiDiachuk

engine/access/rest/websockets/data_providers/account_statuses_provider.go

@@ -111,10 +111,10 @@ func (p *AccountStatusesDataProvider) handleResponse() func(accountStatusesRespo
 			blocksSinceLastMessage = 0
 		}
 
+		index := messageIndex.Value()
 		if ok := messageIndex.Set(messageIndex.Value() + 1); !ok {
 			return status.Errorf(codes.Internal, "message index already incremented to %d", messageIndex.Value())
 		}
-		index := messageIndex.Value()
 
 		p.send <- &models.AccountStatusesResponse{
 			BlockID:       accountStatusesResponse.BlockID.String(),

engine/access/rest/websockets/data_providers/account_statuses_provider_test.go

@@ -254,8 +254,8 @@ func (s *AccountStatusesProviderSuite) TestMessageIndexAccountStatusesProviderRe
 		responses = append(responses, accountStatusesRes)
 	}
 
-	// Verifying that indices are starting from 1
-	s.Require().Equal(uint64(1), responses[0].MessageIndex, "Expected MessageIndex to start with 1")
+	// Verifying that indices are starting from 0
+	s.Require().Equal(uint64(0), responses[0].MessageIndex, "Expected MessageIndex to start with 0")
 
 	// Verifying that indices are strictly increasing
 	for i := 1; i < len(responses); i++ {

engine/access/rest/websockets/data_providers/events_provider.go

@@ -97,10 +97,10 @@ func (p *EventsDataProvider) handleResponse() func(eventsResponse *backend.Event
 			blocksSinceLastMessage = 0
 		}
 
+		index := messageIndex.Value()
 		if ok := messageIndex.Set(messageIndex.Value() + 1); !ok {
 			return fmt.Errorf("message index already incremented to: %d", messageIndex.Value())
 		}
-		index := messageIndex.Value()
 
 		p.send <- &models.EventResponse{
 			BlockId:        eventsResponse.BlockID.String(),

engine/access/rest/websockets/data_providers/events_provider_test.go

@@ -282,7 +282,7 @@ func (s *EventsProviderSuite) TestMessageIndexEventProviderResponse_HappyPath()
 	}
 
 	// Verifying that indices are starting from 1
-	s.Require().Equal(uint64(1), responses[0].MessageIndex, "Expected MessageIndex to start with 1")
+	s.Require().Equal(uint64(0), responses[0].MessageIndex, "Expected MessageIndex to start with 0")
 
 	// Verifying that indices are strictly increasing
 	for i := 1; i < len(responses); i++ {