common: fix profit fixer batch query

pkg/strategy/common/profit_fixer.go

@@ -39,9 +39,9 @@ func (f *ProfitFixer) batchQueryTrades(
 	service types.ExchangeTradeHistoryService,
 	symbol string,
 	since, until time.Time,
-) ([]types.Trade, error) {
+) (chan types.Trade, chan error) {
 	q := &batch.TradeBatchQuery{ExchangeTradeHistoryService: service}
-	return q.QueryTrades(ctx, symbol, &types.TradeQueryOptions{
+	return q.Query(ctx, symbol, &types.TradeQueryOptions{
 		StartTime: &since,
 		EndTime:   &until,
 	})
@@ -58,24 +58,37 @@ func (f *ProfitFixer) aggregateAllTrades(ctx context.Context, symbol string, sin
 		service := s
 		g.Go(func() error {
 			log.Infof("batch querying %s trade history from %s since %s until %s", symbol, sessionName, since.String(), until.String())
-			trades, err := f.batchQueryTrades(subCtx, service, symbol, since, until)
-			if err != nil {
-				log.WithError(err).Errorf("unable to batch query trades for fixer")
-				return err
-			}
+			tradeC, errC := f.batchQueryTrades(subCtx, service, symbol, since, until)
+
+			for {
+				select {
+				case <-ctx.Done():
+					return ctx.Err()
+
+				case err := <-errC:
+					return err
 
-			mu.Lock()
-			allTrades = append(allTrades, trades...)
-			mu.Unlock()
-			return nil
+				case trade, ok := <-tradeC:
+					if !ok {
+						return nil
+					}
+
+					mu.Lock()
+					allTrades = append(allTrades, trade)
+					mu.Unlock()
+				}
+			}
 		})
 	}
 
 	if err := g.Wait(); err != nil {
 		return nil, err
 	}
 
+	mu.Lock()
 	allTrades = types.SortTradesAscending(allTrades)
+	mu.Unlock()
+
 	return allTrades, nil
 }