Fix storage/remote/codec ignoreing histogram reset hint

Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>

storage/remote/codec.go

@@ -528,6 +528,7 @@ func exemplarProtoToExemplar(ep prompb.Exemplar) exemplar.Exemplar {
 // represents an integer histogram and not a float histogram.
 func HistogramProtoToHistogram(hp prompb.Histogram) *histogram.Histogram {
 	return &histogram.Histogram{
+		CounterResetHint: histogram.CounterResetHint(hp.ResetHint),
 		Schema:           hp.Schema,
 		ZeroThreshold:    hp.ZeroThreshold,
 		ZeroCount:        hp.GetZeroCountInt(),
@@ -545,6 +546,7 @@ func HistogramProtoToHistogram(hp prompb.Histogram) *histogram.Histogram {
 // the proto message represents an float histogram and not a integer histogram.
 func HistogramProtoToFloatHistogram(hp prompb.Histogram) *histogram.FloatHistogram {
 	return &histogram.FloatHistogram{
+		CounterResetHint: histogram.CounterResetHint(hp.ResetHint),
 		Schema:           hp.Schema,
 		ZeroThreshold:    hp.ZeroThreshold,
 		ZeroCount:        hp.GetZeroCountFloat(),
@@ -577,6 +579,7 @@ func HistogramToHistogramProto(timestamp int64, h *histogram.Histogram) prompb.H
 		NegativeDeltas: h.NegativeBuckets,
 		PositiveSpans:  spansToSpansProto(h.PositiveSpans),
 		PositiveDeltas: h.PositiveBuckets,
+		ResetHint:      prompb.Histogram_ResetHint(h.CounterResetHint),
 		Timestamp:      timestamp,
 	}
 }
@@ -592,6 +595,7 @@ func FloatHistogramToHistogramProto(timestamp int64, fh *histogram.FloatHistogra
 		NegativeCounts: fh.NegativeBuckets,
 		PositiveSpans:  spansToSpansProto(fh.PositiveSpans),
 		PositiveCounts: fh.PositiveBuckets,
+		ResetHint:      prompb.Histogram_ResetHint(fh.CounterResetHint),
 		Timestamp:      timestamp,
 	}
 }

storage/remote/codec_test.go

@@ -371,6 +371,202 @@ func TestNilHistogramProto(t *testing.T) {
 	HistogramProtoToFloatHistogram(prompb.Histogram{})
 }
 
+func exampleHistogram() histogram.Histogram {
+	return histogram.Histogram{
+		CounterResetHint: histogram.GaugeType,
+		Schema:           0,
+		Count:            19,
+		Sum:              2.7,
+		PositiveSpans: []histogram.Span{
+			{Offset: 0, Length: 4},
+			{Offset: 0, Length: 0},
+			{Offset: 0, Length: 3},
+		},
+		PositiveBuckets: []int64{1, 2, -2, 1, -1, 0, 0},
+		NegativeSpans: []histogram.Span{
+			{Offset: 0, Length: 5},
+			{Offset: 1, Length: 0},
+			{Offset: 0, Length: 1},
+		},
+		NegativeBuckets: []int64{1, 2, -2, 1, -1, 0},
+	}
+}
+
+func exampleHistogramProto() prompb.Histogram {
+	return prompb.Histogram{
+		Count:         &prompb.Histogram_CountInt{CountInt: 19},
+		Sum:           2.7,
+		Schema:        0,
+		ZeroThreshold: 0,
+		ZeroCount:     &prompb.Histogram_ZeroCountInt{ZeroCountInt: 0},
+		NegativeSpans: []*prompb.BucketSpan{
+			{
+				Offset: 0,
+				Length: 5,
+			},
+			{
+				Offset: 1,
+				Length: 0,
+			},
+			{
+				Offset: 0,
+				Length: 1,
+			},
+		},
+		NegativeDeltas: []int64{1, 2, -2, 1, -1, 0},
+		PositiveSpans: []*prompb.BucketSpan{
+			{
+				Offset: 0,
+				Length: 4,
+			},
+			{
+				Offset: 0,
+				Length: 0,
+			},
+			{
+				Offset: 0,
+				Length: 3,
+			},
+		},
+		PositiveDeltas: []int64{1, 2, -2, 1, -1, 0, 0},
+		ResetHint:      prompb.Histogram_GAUGE,
+		Timestamp:      1337,
+	}
+}
+
+func TestHistogramToProtoConvert(t *testing.T) {
+	tests := []struct {
+		input    histogram.CounterResetHint
+		expected prompb.Histogram_ResetHint
+	}{
+		{
+			input:    histogram.UnknownCounterReset,
+			expected: prompb.Histogram_UNKNOWN,
+		},
+		{
+			input:    histogram.CounterReset,
+			expected: prompb.Histogram_YES,
+		},
+		{
+			input:    histogram.NotCounterReset,
+			expected: prompb.Histogram_NO,
+		},
+		{
+			input:    histogram.GaugeType,
+			expected: prompb.Histogram_GAUGE,
+		},
+	}
+
+	for _, test := range tests {
+		h := exampleHistogram()
+		h.CounterResetHint = test.input
+		p := exampleHistogramProto()
+		p.ResetHint = test.expected
+
+		require.Equal(t, p, HistogramToHistogramProto(1337, &h))
+
+		require.Equal(t, h, *HistogramProtoToHistogram(p))
+	}
+}
+
+func exampleFloatHistogram() histogram.FloatHistogram {
+	return histogram.FloatHistogram{
+		CounterResetHint: histogram.GaugeType,
+		Schema:           0,
+		Count:            19,
+		Sum:              2.7,
+		PositiveSpans: []histogram.Span{
+			{Offset: 0, Length: 4},
+			{Offset: 0, Length: 0},
+			{Offset: 0, Length: 3},
+		},
+		PositiveBuckets: []float64{1, 2, -2, 1, -1, 0, 0},
+		NegativeSpans: []histogram.Span{
+			{Offset: 0, Length: 5},
+			{Offset: 1, Length: 0},
+			{Offset: 0, Length: 1},
+		},
+		NegativeBuckets: []float64{1, 2, -2, 1, -1, 0},
+	}
+}
+
+func exampleFloatHistogramProto() prompb.Histogram {
+	return prompb.Histogram{
+		Count:         &prompb.Histogram_CountFloat{CountFloat: 19},
+		Sum:           2.7,
+		Schema:        0,
+		ZeroThreshold: 0,
+		ZeroCount:     &prompb.Histogram_ZeroCountFloat{ZeroCountFloat: 0},
+		NegativeSpans: []*prompb.BucketSpan{
+			{
+				Offset: 0,
+				Length: 5,
+			},
+			{
+				Offset: 1,
+				Length: 0,
+			},
+			{
+				Offset: 0,
+				Length: 1,
+			},
+		},
+		NegativeCounts: []float64{1, 2, -2, 1, -1, 0},
+		PositiveSpans: []*prompb.BucketSpan{
+			{
+				Offset: 0,
+				Length: 4,
+			},
+			{
+				Offset: 0,
+				Length: 0,
+			},
+			{
+				Offset: 0,
+				Length: 3,
+			},
+		},
+		PositiveCounts: []float64{1, 2, -2, 1, -1, 0, 0},
+		ResetHint:      prompb.Histogram_GAUGE,
+		Timestamp:      1337,
+	}
+}
+
+func TestFloatHistogramToProtoConvert(t *testing.T) {
+	tests := []struct {
+		input    histogram.CounterResetHint
+		expected prompb.Histogram_ResetHint
+	}{
+		{
+			input:    histogram.UnknownCounterReset,
+			expected: prompb.Histogram_UNKNOWN,
+		},
+		{
+			input:    histogram.CounterReset,
+			expected: prompb.Histogram_YES,
+		},
+		{
+			input:    histogram.NotCounterReset,
+			expected: prompb.Histogram_NO,
+		},
+		{
+			input:    histogram.GaugeType,
+			expected: prompb.Histogram_GAUGE,
+		},
+	}
+
+	for _, test := range tests {
+		h := exampleFloatHistogram()
+		h.CounterResetHint = test.input
+		p := exampleFloatHistogramProto()
+		p.ResetHint = test.expected
+
+		require.Equal(t, p, FloatHistogramToHistogramProto(1337, &h))
+
+		require.Equal(t, h, *HistogramProtoToFloatHistogram(p))
+	}
+}
+
 func TestStreamResponse(t *testing.T) {
 	lbs1 := labelsToLabelsProto(labels.FromStrings("instance", "localhost1", "job", "demo1"), nil)
 	lbs2 := labelsToLabelsProto(labels.FromStrings("instance", "localhost2", "job", "demo2"), nil)