From adc36d00b703c7544a8c6351aba30e073b1ba051 Mon Sep 17 00:00:00 2001
From: Aliaksandr Valialkin <valyala@gmail.com>
Date: Fri, 10 Jan 2020 21:56:59 +0200
Subject: [PATCH] app/vmselect/promql: properly handle
 `aggr(aggr_over_time(...))`

---
 app/vmselect/promql/exec_test.go | 35 ++++++++++++++++++++++++++++++++
 app/vmselect/promql/rollup.go    |  9 ++++++++
 2 files changed, 44 insertions(+)

diff --git a/app/vmselect/promql/exec_test.go b/app/vmselect/promql/exec_test.go
index 769a0e4b5a..4c613fe870 100644
--- a/app/vmselect/promql/exec_test.go
+++ b/app/vmselect/promql/exec_test.go
@@ -4538,6 +4538,41 @@ func TestExecSuccess(t *testing.T) {
 		resultExpected := []netstorage.Result{r1, r2, r3}
 		f(q, resultExpected)
 	})
+	t.Run(`avg(aggr_over_time(multi-func))`, func(t *testing.T) {
+		t.Parallel()
+		q := `avg(aggr_over_time(("min_over_time", "max_over_time"), time()[:10s]))`
+		r := netstorage.Result{
+			MetricName: metricNameExpected,
+			Values:     []float64{900, 1100, 1300, 1500, 1700, 1900},
+			Timestamps: timestampsExpected,
+		}
+		resultExpected := []netstorage.Result{r}
+		f(q, resultExpected)
+	})
+	t.Run(`avg(aggr_over_time(multi-func)) by (rollup)`, func(t *testing.T) {
+		t.Parallel()
+		q := `sort(avg(aggr_over_time(("min_over_time", "max_over_time"), time()[:10s])) by (rollup))`
+		r1 := netstorage.Result{
+			MetricName: metricNameExpected,
+			Values:     []float64{800, 1000, 1200, 1400, 1600, 1800},
+			Timestamps: timestampsExpected,
+		}
+		r1.MetricName.Tags = []storage.Tag{{
+			Key:   []byte("rollup"),
+			Value: []byte("min_over_time"),
+		}}
+		r2 := netstorage.Result{
+			MetricName: metricNameExpected,
+			Values:     []float64{1000, 1200, 1400, 1600, 1800, 2000},
+			Timestamps: timestampsExpected,
+		}
+		r2.MetricName.Tags = []storage.Tag{{
+			Key:   []byte("rollup"),
+			Value: []byte("max_over_time"),
+		}}
+		resultExpected := []netstorage.Result{r1, r2}
+		f(q, resultExpected)
+	})
 	t.Run(`rollup_candlestick()`, func(t *testing.T) {
 		t.Parallel()
 		q := `sort(rollup_candlestick(round(rand(0),0.01)[:10s]))`
diff --git a/app/vmselect/promql/rollup.go b/app/vmselect/promql/rollup.go
index bd0733b3ed..385f702895 100644
--- a/app/vmselect/promql/rollup.go
+++ b/app/vmselect/promql/rollup.go
@@ -136,6 +136,15 @@ var rollupFuncsKeepMetricGroup = map[string]bool{
 }
 
 func getRollupAggrFuncNames(expr metricsql.Expr) ([]string, error) {
+	afe, ok := expr.(*metricsql.AggrFuncExpr)
+	if ok {
+		// This is for incremental aggregate function case:
+		//
+		//     sum(aggr_over_time(...))
+		//
+		// See aggr_incremental.go for details.
+		expr = afe.Args[0]
+	}
 	fe, ok := expr.(*metricsql.FuncExpr)
 	if !ok {
 		logger.Panicf("BUG: unexpected expression; want metricsql.FuncExpr; got %T; value: %s", expr, expr.AppendString(nil))