Merge branch 'master' into linasn/read-handler-hooks

* master:
  [dbnode] Update series metadata type name. (#2946)
  [aggregator/client] Include instance ID in write errors (#2945)
  Revert "[dbnode] Properly rebuild index segments if they fail verification. (#2879)" (#2944)
  [dbnode] Add DocRef() to NS and multiple series metadata types  (#2931)
  [dbnode] Remove dead code in fs package (#2932)
  [query] Fix incorrect content type in m3query/ error response (#2917)
  [query] Graphite query timeout propagation and add per endpoint status/latency metrics (#2880)
  [query] Allow Graphite variadic functions to omit variadic args (#2882)
  [aggregator] Return NaN instead of 0 for NaN gauge values (#2930)
  [aggregator] Use NaN instead of math.MaxFloat64 and add sentinel guards (#2929)

# Conflicts:
#	src/query/api/v1/handler/prom/read.go
#	src/query/api/v1/handler/prom/read_instant.go
#	src/query/api/v1/handler/prom/read_test.go
#	src/query/api/v1/httpd/handler_test.go

site/.htmltest.yml

@@ -18,5 +18,7 @@ IgnoreURLs:
 - "youtu.be"
 - "youtube.com"
 - "cassandra.apache.org"
+- "slideshare.net"
+- "meetup.com"
 - "github.com/m3db/m3/tree/docs-test/site/content/docs"
 - "github.com/m3db/m3/tree/master/site/content/docs"

src/aggregator/aggregation/gauge.go

@@ -27,10 +27,6 @@ import (
 	"github.com/m3db/m3/src/metrics/aggregation"
 )
 
-const (
-	minFloat64 = -math.MaxFloat64
-)
-
 // Gauge aggregates gauge values.
 type Gauge struct {
 	Options
@@ -48,8 +44,8 @@ type Gauge struct {
 func NewGauge(opts Options) Gauge {
 	return Gauge{
 		Options: opts,
-		max:     minFloat64,
-		min:     math.MaxFloat64,
+		max:     math.NaN(),
+		min:     math.NaN(),
 	}
 }
 
@@ -65,12 +61,17 @@ func (g *Gauge) Update(timestamp time.Time, value float64) {
 		g.Options.Metrics.Gauge.IncValuesOutOfOrder()
 	}
 
-	g.sum += value
 	g.count++
-	if g.max < value {
+
+	if math.IsNaN(value) {
+		return
+	}
+
+	g.sum += value
+	if math.IsNaN(g.max) || g.max < value {
 		g.max = value
 	}
-	if g.min > value {
+	if math.IsNaN(g.min) || g.min > value {
 		g.min = value
 	}
 
@@ -108,10 +109,14 @@ func (g *Gauge) Stdev() float64 {
 }
 
 // Min returns the minimum gauge value.
-func (g *Gauge) Min() float64 { return g.min }
+func (g *Gauge) Min() float64 {
+	return g.min
+}
 
 // Max returns the maximum gauge value.
-func (g *Gauge) Max() float64 { return g.max }
+func (g *Gauge) Max() float64 {
+	return g.max
+}
 
 // ValueOf returns the value for the aggregation type.
 func (g *Gauge) ValueOf(aggType aggregation.Type) float64 {

src/aggregator/aggregation/gauge_test.go

@@ -21,6 +21,7 @@
 package aggregation
 
 import (
+	"math"
 	"testing"
 	"time"
 
@@ -42,6 +43,17 @@ func TestGaugeDefaultAggregationType(t *testing.T) {
 	require.Equal(t, 100.0, g.ValueOf(aggregation.Count))
 	require.Equal(t, 50.5, g.ValueOf(aggregation.Mean))
 	require.Equal(t, 0.0, g.ValueOf(aggregation.SumSq))
+	require.Equal(t, 100.0, g.ValueOf(aggregation.Max))
+	require.Equal(t, 1.0, g.ValueOf(aggregation.Min))
+
+	g = NewGauge(NewOptions(instrument.NewOptions()))
+	require.Equal(t, 0.0, g.Last())
+	require.Equal(t, 0.0, g.ValueOf(aggregation.Last))
+	require.Equal(t, 0.0, g.ValueOf(aggregation.Count))
+	require.Equal(t, 0.0, g.ValueOf(aggregation.Mean))
+	require.Equal(t, 0.0, g.ValueOf(aggregation.SumSq))
+	require.True(t, math.IsNaN(g.ValueOf(aggregation.Max)))
+	require.True(t, math.IsNaN(g.ValueOf(aggregation.Min)))
 }
 
 func TestGaugeCustomAggregationType(t *testing.T) {
@@ -80,6 +92,33 @@ func TestGaugeCustomAggregationType(t *testing.T) {
 			require.False(t, aggType.IsValidForGauge())
 		}
 	}
+
+	g = NewGauge(opts)
+	require.Equal(t, 0.0, g.Last())
+	for aggType := range aggregation.ValidTypes {
+		v := g.ValueOf(aggType)
+		switch aggType {
+		case aggregation.Last:
+			require.Equal(t, 0.0, v)
+		case aggregation.Min:
+			require.True(t, math.IsNaN(v))
+		case aggregation.Max:
+			require.True(t, math.IsNaN(v))
+		case aggregation.Mean:
+			require.Equal(t, 0.0, v)
+		case aggregation.Count:
+			require.Equal(t, 0.0, v)
+		case aggregation.Sum:
+			require.Equal(t, 0.0, v)
+		case aggregation.SumSq:
+			require.Equal(t, 0.0, v)
+		case aggregation.Stdev:
+			require.InDelta(t, 0.0, v, 0.0)
+		default:
+			require.Equal(t, 0.0, v)
+			require.False(t, aggType.IsValidForGauge())
+		}
+	}
 }
 
 func TestGaugeLastOutOfOrderValues(t *testing.T) {

src/aggregator/client/queue.go

@@ -218,6 +218,7 @@ func (q *queue) writeAndReset() {
 	if err := q.writeFn(q.buf); err != nil {
 		q.log.Error("error writing data",
 			zap.Int("buffer_size", len(q.buf)),
+			zap.String("target_instance_id", q.instance.ID()),
 			zap.String("target_instance", q.instance.Endpoint()),
 			zap.Error(err),
 		)

src/cmd/tools/dtest/docker/harness/carbon_test.go

@@ -32,7 +32,7 @@ import (
 )
 
 func findVerifier(expected string) resources.ResponseVerifier {
-	return func(status int, s string, err error) error {
+	return func(status int, _ map[string][]string, s string, err error) error {
 		if err != nil {
 			return err
 		}
@@ -55,7 +55,7 @@ func renderVerifier(v float64) resources.ResponseVerifier {
 		Datapoints [][]float64 `json:"datapoints"`
 	}
 
-	return func(status int, s string, err error) error {
+	return func(status int, _ map[string][]string, s string, err error) error {
 		if err != nil {
 			return err
 		}

src/cmd/tools/dtest/docker/harness/query_api_test.go

@@ -71,7 +71,7 @@ func testInvalidQueryReturns400(t *testing.T, tests []urlTest) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			assert.NoError(t, coord.RunQuery(verifyStatus(400), tt.url), "for query '%v'", tt.url)
+			assert.NoError(t, coord.RunQuery(verifyResponse(400), tt.url), "for query '%v'", tt.url)
 		})
 	}
 }
@@ -129,8 +129,8 @@ func queryString(params map[string]string) string {
 	return strings.Join(p, "&")
 }
 
-func verifyStatus(expectedStatus int) resources.ResponseVerifier {
-	return func(status int, resp string, err error) error {
+func verifyResponse(expectedStatus int) resources.ResponseVerifier {
+	return func(status int, headers map[string][]string, resp string, err error) error {
 		if err != nil {
 			return err
 		}
@@ -139,6 +139,12 @@ func verifyStatus(expectedStatus int) resources.ResponseVerifier {
 			return fmt.Errorf("expeceted %v status code, got %v", expectedStatus, status)
 		}
 
+		if contentType, ok := headers["Content-Type"]; !ok {
+			return fmt.Errorf("missing Content-Type header")
+		} else if len(contentType) != 1 || contentType[0] != "application/json" {
+			return fmt.Errorf("expected json content type, got %v", contentType)
+		}
+
 		return nil
 	}
 }

src/cmd/tools/dtest/docker/harness/resources/coordinator.go

@@ -55,7 +55,7 @@ var (
 )
 
 // ResponseVerifier is a function that checks if the query response is valid.
-type ResponseVerifier func(int, string, error) error
+type ResponseVerifier func(int, map[string][]string, string, error) error
 
 // Coordinator is a wrapper for a coordinator. It provides a wrapper on HTTP
 // endpoints that expose cluster management APIs as well as read and write
@@ -363,7 +363,7 @@ func (c *coordinator) query(
 	defer resp.Body.Close()
 	b, err := ioutil.ReadAll(resp.Body)
 
-	return verifier(resp.StatusCode, string(b), err)
+	return verifier(resp.StatusCode, resp.Header, string(b), err)
 }
 
 func (c *coordinator) RunQuery(

src/dbnode/generated/mocks/generate.go

@@ -20,7 +20,7 @@
 
 // mockgen rules for generating mocks for exported interfaces (reflection mode)
 
-//go:generate sh -c "mockgen -package=fs $PACKAGE/src/dbnode/persist/fs CrossBlockReader,CrossBlockIterator,DataFileSetWriter,DataFileSetReader,DataFileSetSeeker,IndexFileSetWriter,IndexFileSetReader,IndexSegmentFileSetWriter,IndexSegmentFileSet,IndexSegmentFile,SnapshotMetadataFileWriter,DataFileSetSeekerManager,ConcurrentDataFileSetSeeker,MergeWith,StreamingWriter | genclean -pkg $PACKAGE/src/dbnode/persist/fs -out $GOPATH/src/$PACKAGE/src/dbnode/persist/fs/fs_mock.go"
+//go:generate sh -c "mockgen -package=fs $PACKAGE/src/dbnode/persist/fs DataFileSetWriter,DataFileSetReader,DataFileSetSeeker,IndexFileSetWriter,IndexFileSetReader,IndexSegmentFileSetWriter,IndexSegmentFileSet,IndexSegmentFile,SnapshotMetadataFileWriter,DataFileSetSeekerManager,ConcurrentDataFileSetSeeker,MergeWith,StreamingWriter | genclean -pkg $PACKAGE/src/dbnode/persist/fs -out $GOPATH/src/$PACKAGE/src/dbnode/persist/fs/fs_mock.go"
 //go:generate sh -c "mockgen -package=xio $PACKAGE/src/dbnode/x/xio SegmentReader,SegmentReaderPool | genclean -pkg $PACKAGE/src/dbnode/x/xio -out $GOPATH/src/$PACKAGE/src/dbnode/x/xio/io_mock.go"
 //go:generate sh -c "mockgen -package=digest -destination=$GOPATH/src/$PACKAGE/src/dbnode/digest/digest_mock.go $PACKAGE/src/dbnode/digest ReaderWithDigest"
 //go:generate sh -c "mockgen -package=series $PACKAGE/src/dbnode/storage/series DatabaseSeries,QueryableBlockRetriever | genclean -pkg $PACKAGE/src/dbnode/storage/series -out $GOPATH/src/$PACKAGE/src/dbnode/storage/series/series_mock.go"