store: proxy: fix queries never timing out bug (#2411)

CHANGELOG.md

@@ -11,6 +11,10 @@ We use *breaking* word for marking changes that are not backward compatible (rel
 
 ## Unreleased
 
+### Fixed
+
+- [#2411](https://github.com/thanos-io/thanos/pull/2411) Query: fix a bug where queries might not time out sometimes due to issues with one or more StoreAPIs
+
 ## [v0.12.0](https://github.com/thanos-io/thanos/releases/tag/v0.12.0) - 2020.04.15
 
 ### Fixed

pkg/store/proxy.go

@@ -434,7 +434,12 @@ func startStreamSeriesSet(
 				s.warnCh.send(storepb.NewWarnSeriesResponse(errors.New(w)))
 				continue
 			}
-			s.recvCh <- rr.r.GetSeries()
+			select {
+			case s.recvCh <- rr.r.GetSeries():
+			case <-ctx.Done():
+				s.handleErr(errors.Wrapf(ctx.Err(), "failed to receive any data from %s", s.name), done)
+				return
+			}
 		}
 	}()
 	return s

pkg/store/proxy_test.go

@@ -462,6 +462,60 @@ func TestProxyStore_SeriesSlowStores(t *testing.T) {
 		expectedErr         error
 		expectedWarningsLen int
 	}{
+		{
+			title: "partial response disabled; 1st errors out after some delay; 2nd store is fast",
+			storeAPIs: []Client{
+				&testClient{
+					StoreClient: &mockedStoreAPI{
+						RespSeries: []*storepb.SeriesResponse{
+							storepb.NewWarnSeriesResponse(errors.New("warning")),
+							storeSeriesResponse(t, labels.FromStrings("a", "b"), []sample{{1, 1}, {2, 2}, {3, 3}}),
+						},
+						RespDuration:       2 * time.Second,
+						SlowSeriesIndex:    1,
+						injectedError:      errors.New("test"),
+						injectedErrorIndex: 1,
+					},
+					labelSets: []storepb.LabelSet{{Labels: []storepb.Label{{Name: "ext", Value: "1"}}}},
+					minTime:   1,
+					maxTime:   300,
+				},
+				&testClient{
+					StoreClient: &mockedStoreAPI{
+						RespSeries: []*storepb.SeriesResponse{
+							storepb.NewWarnSeriesResponse(errors.New("warning")),
+							storeSeriesResponse(t, labels.FromStrings("b", "a"), []sample{{4, 1}, {5, 2}, {6, 3}}),
+							storeSeriesResponse(t, labels.FromStrings("b", "a"), []sample{{4, 1}, {5, 2}, {6, 3}}),
+							storeSeriesResponse(t, labels.FromStrings("b", "a"), []sample{{4, 1}, {5, 2}, {6, 3}}),
+							storeSeriesResponse(t, labels.FromStrings("b", "a"), []sample{{4, 1}, {5, 2}, {6, 3}}),
+							storeSeriesResponse(t, labels.FromStrings("b", "a"), []sample{{4, 1}, {5, 2}, {6, 3}}),
+
+							storeSeriesResponse(t, labels.FromStrings("b", "a"), []sample{{4, 1}, {5, 2}, {6, 3}}),
+							storeSeriesResponse(t, labels.FromStrings("b", "a"), []sample{{4, 1}, {5, 2}, {6, 3}}),
+							storeSeriesResponse(t, labels.FromStrings("b", "a"), []sample{{4, 1}, {5, 2}, {6, 3}}),
+							storeSeriesResponse(t, labels.FromStrings("b", "a"), []sample{{4, 1}, {5, 2}, {6, 3}}),
+							storeSeriesResponse(t, labels.FromStrings("b", "a"), []sample{{4, 1}, {5, 2}, {6, 3}}),
+
+							storeSeriesResponse(t, labels.FromStrings("b", "a"), []sample{{4, 1}, {5, 2}, {6, 3}}),
+							storeSeriesResponse(t, labels.FromStrings("b", "a"), []sample{{4, 1}, {5, 2}, {6, 3}}),
+							storeSeriesResponse(t, labels.FromStrings("b", "a"), []sample{{4, 1}, {5, 2}, {6, 3}}),
+							storeSeriesResponse(t, labels.FromStrings("b", "a"), []sample{{4, 1}, {5, 2}, {6, 3}}),
+							storeSeriesResponse(t, labels.FromStrings("b", "a"), []sample{{4, 1}, {5, 2}, {6, 3}}),
+						},
+					},
+					labelSets: []storepb.LabelSet{{Labels: []storepb.Label{{Name: "ext", Value: "1"}}}},
+					minTime:   1,
+					maxTime:   300,
+				},
+			},
+			req: &storepb.SeriesRequest{
+				MinTime:                 1,
+				MaxTime:                 300,
+				Matchers:                []storepb.LabelMatcher{{Name: "ext", Value: "1", Type: storepb.LabelMatcher_EQ}},
+				PartialResponseDisabled: true,
+			},
+			expectedErr: errors.New("test: receive series from test: test"),
+		},
 		{
 			title: "partial response disabled; 1st store is slow, 2nd store is fast;",
 			storeAPIs: []Client{
@@ -1349,6 +1403,10 @@ type mockedStoreAPI struct {
 	LastSeriesReq      *storepb.SeriesRequest
 	LastLabelValuesReq *storepb.LabelValuesRequest
 	LastLabelNamesReq  *storepb.LabelNamesRequest
+
+	// injectedError will be injected into Recv() if not nil.
+	injectedError      error
+	injectedErrorIndex int
 }
 
 func (s *mockedStoreAPI) Info(ctx context.Context, req *storepb.InfoRequest, _ ...grpc.CallOption) (*storepb.InfoResponse, error) {
@@ -1358,7 +1416,7 @@ func (s *mockedStoreAPI) Info(ctx context.Context, req *storepb.InfoRequest, _ .
 func (s *mockedStoreAPI) Series(ctx context.Context, req *storepb.SeriesRequest, _ ...grpc.CallOption) (storepb.Store_SeriesClient, error) {
 	s.LastSeriesReq = req
 
-	return &StoreSeriesClient{ctx: ctx, respSet: s.RespSeries, respDur: s.RespDuration, slowSeriesIndex: s.SlowSeriesIndex}, s.RespError
+	return &StoreSeriesClient{injectedErrorIndex: s.injectedErrorIndex, injectedError: s.injectedError, ctx: ctx, respSet: s.RespSeries, respDur: s.RespDuration, slowSeriesIndex: s.SlowSeriesIndex}, s.RespError
 }
 
 func (s *mockedStoreAPI) LabelNames(ctx context.Context, req *storepb.LabelNamesRequest, _ ...grpc.CallOption) (*storepb.LabelNamesResponse, error) {
@@ -1382,12 +1440,18 @@ type StoreSeriesClient struct {
 	respSet         []*storepb.SeriesResponse
 	respDur         time.Duration
 	slowSeriesIndex int
+
+	injectedError      error
+	injectedErrorIndex int
 }
 
 func (c *StoreSeriesClient) Recv() (*storepb.SeriesResponse, error) {
 	if c.respDur != 0 && (c.slowSeriesIndex == c.i || c.slowSeriesIndex == 0) {
 		time.Sleep(c.respDur)
 	}
+	if c.injectedError != nil && (c.injectedErrorIndex == c.i || c.injectedErrorIndex == 0) {
+		return nil, c.injectedError
+	}
 
 	if c.i >= len(c.respSet) {
 		return nil, io.EOF