Pass query hints down into remote read query proto (#4122)

Signed-off-by: Henri DF <henridf@gmail.com>

prompb/remote.pb.go

@@ -26,6 +26,7 @@
 		Label
 		Labels
 		LabelMatcher
+		ReadHints
 */
 package prompb
 
@@ -99,6 +100,7 @@ type Query struct {
 	StartTimestampMs int64           `protobuf:"varint,1,opt,name=start_timestamp_ms,json=startTimestampMs,proto3" json:"start_timestamp_ms,omitempty"`
 	EndTimestampMs   int64           `protobuf:"varint,2,opt,name=end_timestamp_ms,json=endTimestampMs,proto3" json:"end_timestamp_ms,omitempty"`
 	Matchers         []*LabelMatcher `protobuf:"bytes,3,rep,name=matchers" json:"matchers,omitempty"`
+	Hints            *ReadHints      `protobuf:"bytes,4,opt,name=hints" json:"hints,omitempty"`
 }
 
 func (m *Query) Reset()                    { *m = Query{} }
@@ -127,6 +129,13 @@ func (m *Query) GetMatchers() []*LabelMatcher {
 	return nil
 }
 
+func (m *Query) GetHints() *ReadHints {
+	if m != nil {
+		return m.Hints
+	}
+	return nil
+}
+
 type QueryResult struct {
 	// Samples within a time series must be ordered by time.
 	Timeseries []*TimeSeries `protobuf:"bytes,1,rep,name=timeseries" json:"timeseries,omitempty"`
@@ -278,6 +287,16 @@ func (m *Query) MarshalTo(dAtA []byte) (int, error) {
 			i += n
 		}
 	}
+	if m.Hints != nil {
+		dAtA[i] = 0x22
+		i++
+		i = encodeVarintRemote(dAtA, i, uint64(m.Hints.Size()))
+		n1, err := m.Hints.MarshalTo(dAtA[i:])
+		if err != nil {
+			return 0, err
+		}
+		i += n1
+	}
 	return i, nil
 }
 
@@ -371,6 +390,10 @@ func (m *Query) Size() (n int) {
 			n += 1 + l + sovRemote(uint64(l))
 		}
 	}
+	if m.Hints != nil {
+		l = m.Hints.Size()
+		n += 1 + l + sovRemote(uint64(l))
+	}
 	return n
 }
 
@@ -740,6 +763,39 @@ func (m *Query) Unmarshal(dAtA []byte) error {
 				return err
 			}
 			iNdEx = postIndex
+		case 4:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Hints", wireType)
+			}
+			var msglen int
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowRemote
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				msglen |= (int(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			if msglen < 0 {
+				return ErrInvalidLengthRemote
+			}
+			postIndex := iNdEx + msglen
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			if m.Hints == nil {
+				m.Hints = &ReadHints{}
+			}
+			if err := m.Hints.Unmarshal(dAtA[iNdEx:postIndex]); err != nil {
+				return err
+			}
+			iNdEx = postIndex
 		default:
 			iNdEx = preIndex
 			skippy, err := skipRemote(dAtA[iNdEx:])
@@ -950,23 +1006,25 @@ var (
 func init() { proto.RegisterFile("remote.proto", fileDescriptorRemote) }
 
 var fileDescriptorRemote = []byte{
-	// 284 bytes of a gzipped FileDescriptorProto
+	// 308 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x9c, 0x91, 0xcf, 0x4a, 0xc3, 0x40,
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x9c, 0x91, 0x4f, 0x4b, 0xf3, 0x40,
-	0x10, 0xc6, 0x59, 0x8b, 0xad, 0x4c, 0x8a, 0xd4, 0x45, 0x34, 0x78, 0x08, 0x92, 0x53, 0x40, 0x09,
+	0x10, 0xc6, 0xd9, 0xb7, 0x6f, 0x5b, 0x99, 0x14, 0xa9, 0x8b, 0x7f, 0x82, 0x87, 0x52, 0x72, 0x0a,
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+	0x54, 0x0a, 0x56, 0xf1, 0xe0, 0x4d, 0x41, 0xf1, 0x60, 0x0f, 0xae, 0x05, 0xc1, 0x4b, 0x49, 0xed,
-	0xdd, 0x64, 0xbb, 0x33, 0x39, 0xf4, 0x41, 0x7c, 0x27, 0x8f, 0x3e, 0x82, 0xe4, 0x49, 0xa4, 0x1b,
+	0x40, 0x03, 0xdd, 0x64, 0xbb, 0x33, 0x39, 0xf4, 0xeb, 0x79, 0xf2, 0xe8, 0x47, 0x90, 0x7c, 0x12,
-	0xa2, 0x2b, 0xde, 0x3c, 0xff, 0x7e, 0xdf, 0xc7, 0xc7, 0x0c, 0x8c, 0x2d, 0xea, 0x9a, 0x31, 0x35,
+	0xc9, 0x86, 0xe8, 0x8a, 0x37, 0xcf, 0xbf, 0xdf, 0xf3, 0xf0, 0x0c, 0x03, 0x3d, 0x8b, 0x3a, 0x67,
-	0xb6, 0xe6, 0x5a, 0x82, 0xb1, 0xb5, 0x46, 0x5e, 0x60, 0x43, 0x47, 0x01, 0xaf, 0x0d, 0x52, 0x07,
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+	0x52, 0x8d, 0x8f, 0x8e, 0x2a, 0xcf, 0x8c, 0x2e, 0x21, 0x50, 0x98, 0x2c, 0x9b, 0x9a, 0x11, 0x74,
-	0xbf, 0x63, 0xcf, 0xef, 0x78, 0x6c, 0xd0, 0xae, 0x55, 0x6f, 0xc4, 0x37, 0x30, 0xee, 0xb2, 0x64,
+	0x37, 0x85, 0xdf, 0xb1, 0xe7, 0x77, 0x3c, 0x14, 0x68, 0xb7, 0xaa, 0x31, 0xa2, 0x2b, 0xe8, 0xd5,
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-	0x17, 0x68, 0x29, 0x1c, 0xb8, 0x55, 0xa1, 0xbf, 0xea, 0x21, 0xcb, 0x71, 0x39, 0xed, 0x04, 0xf5,
+	0x84, 0x5f, 0x56, 0x68, 0x29, 0x6c, 0xb9, 0x55, 0xa1, 0xbf, 0xea, 0x3e, 0x59, 0xe0, 0x7a, 0x5a,
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+	0x0b, 0xea, 0xcb, 0x94, 0x23, 0x68, 0xaf, 0xd2, 0x8c, 0x29, 0xfc, 0x3f, 0x14, 0x71, 0x30, 0x39,
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+	0x18, 0x02, 0x00, 0x00,
 }

prompb/remote.proto

@@ -35,6 +35,7 @@ message Query {
   int64 start_timestamp_ms = 1;
   int64 end_timestamp_ms = 2;
   repeated prometheus.LabelMatcher matchers = 3;
+  prometheus.ReadHints hints = 4;
 }
 
 message QueryResult {

prompb/types.pb.go

@@ -165,12 +165,37 @@ func (m *LabelMatcher) GetValue() string {
 	return ""
 }
 
+type ReadHints struct {
+	StepMs int64  `protobuf:"varint,1,opt,name=step_ms,json=stepMs,proto3" json:"step_ms,omitempty"`
+	Func   string `protobuf:"bytes,2,opt,name=func,proto3" json:"func,omitempty"`
+}
+
+func (m *ReadHints) Reset()                    { *m = ReadHints{} }
+func (m *ReadHints) String() string            { return proto.CompactTextString(m) }
+func (*ReadHints) ProtoMessage()               {}
+func (*ReadHints) Descriptor() ([]byte, []int) { return fileDescriptorTypes, []int{5} }
+
+func (m *ReadHints) GetStepMs() int64 {
+	if m != nil {
+		return m.StepMs
+	}
+	return 0
+}
+
+func (m *ReadHints) GetFunc() string {
+	if m != nil {
+		return m.Func
+	}
+	return ""
+}
+
 func init() {
 	proto.RegisterType((*Sample)(nil), "prometheus.Sample")
 	proto.RegisterType((*TimeSeries)(nil), "prometheus.TimeSeries")
 	proto.RegisterType((*Label)(nil), "prometheus.Label")
 	proto.RegisterType((*Labels)(nil), "prometheus.Labels")
 	proto.RegisterType((*LabelMatcher)(nil), "prometheus.LabelMatcher")
+	proto.RegisterType((*ReadHints)(nil), "prometheus.ReadHints")
 	proto.RegisterEnum("prometheus.LabelMatcher_Type", LabelMatcher_Type_name, LabelMatcher_Type_value)
 }
 func (m *Sample) Marshal() (dAtA []byte, err error) {
@@ -339,6 +364,35 @@ func (m *LabelMatcher) MarshalTo(dAtA []byte) (int, error) {
 	return i, nil
 }
 
+func (m *ReadHints) Marshal() (dAtA []byte, err error) {
+	size := m.Size()
+	dAtA = make([]byte, size)
+	n, err := m.MarshalTo(dAtA)
+	if err != nil {
+		return nil, err
+	}
+	return dAtA[:n], nil
+}
+
+func (m *ReadHints) MarshalTo(dAtA []byte) (int, error) {
+	var i int
+	_ = i
+	var l int
+	_ = l
+	if m.StepMs != 0 {
+		dAtA[i] = 0x8
+		i++
+		i = encodeVarintTypes(dAtA, i, uint64(m.StepMs))
+	}
+	if len(m.Func) > 0 {
+		dAtA[i] = 0x12
+		i++
+		i = encodeVarintTypes(dAtA, i, uint64(len(m.Func)))
+		i += copy(dAtA[i:], m.Func)
+	}
+	return i, nil
+}
+
 func encodeVarintTypes(dAtA []byte, offset int, v uint64) int {
 	for v >= 1<<7 {
 		dAtA[offset] = uint8(v&0x7f | 0x80)
@@ -421,6 +475,19 @@ func (m *LabelMatcher) Size() (n int) {
 	return n
 }
 
+func (m *ReadHints) Size() (n int) {
+	var l int
+	_ = l
+	if m.StepMs != 0 {
+		n += 1 + sovTypes(uint64(m.StepMs))
+	}
+	l = len(m.Func)
+	if l > 0 {
+		n += 1 + l + sovTypes(uint64(l))
+	}
+	return n
+}
+
 func sovTypes(x uint64) (n int) {
 	for {
 		n++
@@ -942,6 +1009,104 @@ func (m *LabelMatcher) Unmarshal(dAtA []byte) error {
 	}
 	return nil
 }
+func (m *ReadHints) Unmarshal(dAtA []byte) error {
+	l := len(dAtA)
+	iNdEx := 0
+	for iNdEx < l {
+		preIndex := iNdEx
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if shift >= 64 {
+				return ErrIntOverflowTypes
+			}
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := dAtA[iNdEx]
+			iNdEx++
+			wire |= (uint64(b) & 0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		if wireType == 4 {
+			return fmt.Errorf("proto: ReadHints: wiretype end group for non-group")
+		}
+		if fieldNum <= 0 {
+			return fmt.Errorf("proto: ReadHints: illegal tag %d (wire type %d)", fieldNum, wire)
+		}
+		switch fieldNum {
+		case 1:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field StepMs", wireType)
+			}
+			m.StepMs = 0
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowTypes
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				m.StepMs |= (int64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		case 2:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Func", wireType)
+			}
+			var stringLen uint64
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowTypes
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				stringLen |= (uint64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			intStringLen := int(stringLen)
+			if intStringLen < 0 {
+				return ErrInvalidLengthTypes
+			}
+			postIndex := iNdEx + intStringLen
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			m.Func = string(dAtA[iNdEx:postIndex])
+			iNdEx = postIndex
+		default:
+			iNdEx = preIndex
+			skippy, err := skipTypes(dAtA[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if skippy < 0 {
+				return ErrInvalidLengthTypes
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			iNdEx += skippy
+		}
+	}
+
+	if iNdEx > l {
+		return io.ErrUnexpectedEOF
+	}
+	return nil
+}
 func skipTypes(dAtA []byte) (n int, err error) {
 	l := len(dAtA)
 	iNdEx := 0
@@ -1050,25 +1215,28 @@ var (
 func init() { proto.RegisterFile("types.proto", fileDescriptorTypes) }
 
 var fileDescriptorTypes = []byte{
-	// 316 bytes of a gzipped FileDescriptorProto
+	// 353 bytes of a gzipped FileDescriptorProto
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-	0x2e, 0x9c, 0x62, 0x9b, 0xd9, 0xb9, 0xf6, 0xf6, 0x6c, 0xe8, 0x96, 0xe4, 0x0e, 0xc2, 0x89, 0xab,
+	0x29, 0x38, 0xcb, 0x84, 0x97, 0x8a, 0x75, 0x66, 0xe6, 0x83, 0xb7, 0x65, 0xc2, 0x72, 0x09, 0x6e,
-	0x1a, 0xfc, 0x69, 0x35, 0x0e, 0x76, 0x1f, 0x57, 0x8d, 0xa3, 0x5b, 0xf2, 0x46, 0xe0, 0x9f, 0xcd,
+	0xc0, 0x1d, 0x94, 0x55, 0x9d, 0x5f, 0xad, 0xfa, 0xce, 0xe6, 0xfd, 0xbc, 0xb2, 0x77, 0x0b, 0x5e,
-	0x1f, 0xb8, 0x7e, 0x5e, 0x61, 0x45, 0x87, 0x10, 0x98, 0x9f, 0x6a, 0x5b, 0xff, 0x8f, 0x2e, 0x7f,
+	0x09, 0xfc, 0x31, 0xf9, 0x30, 0x51, 0xb3, 0x05, 0x16, 0xb4, 0x0b, 0x8e, 0xfe, 0xa9, 0xa6, 0xf5,
-	0xdc, 0x1f, 0xb8, 0x6c, 0xbe, 0x95, 0xc8, 0x2c, 0xfa, 0x2d, 0xea, 0xfd, 0x26, 0xea, 0x9f, 0x8a,
+	0x6f, 0xef, 0xec, 0xdb, 0xfd, 0x8e, 0x8b, 0x26, 0x6b, 0x81, 0xcc, 0xa0, 0x5f, 0xa2, 0xd6, 0x4f,
-	0xa6, 0x10, 0x98, 0x3b, 0x1a, 0x82, 0x97, 0x4f, 0xa3, 0x06, 0x6d, 0x81, 0xff, 0x98, 0x4f, 0x23,
+	0xa2, 0xf6, 0xb1, 0x68, 0x08, 0x8e, 0xbe, 0xa3, 0x2e, 0x58, 0xf1, 0xc8, 0xab, 0xd0, 0x1a, 0xd8,
-	0x62, 0x02, 0x96, 0x47, 0x9e, 0x0d, 0x58, 0x1e, 0xf9, 0xe3, 0xee, 0x6e, 0xdf, 0x23, 0xef, 0xfb,
+	0xf7, 0xf1, 0xc8, 0x23, 0x3a, 0x60, 0xb1, 0x67, 0x99, 0x80, 0xc5, 0x9e, 0x1d, 0x5c, 0x43, 0x9d,
-	0x1e, 0xf9, 0xdc, 0xf7, 0xc8, 0x53, 0x68, 0x2c, 0xe4, 0x62, 0x11, 0xda, 0x77, 0xbc, 0xfd, 0x0a,
+	0x61, 0xf2, 0x74, 0x97, 0x2e, 0x95, 0xa4, 0xff, 0xa1, 0x26, 0x15, 0x8a, 0x47, 0x2e, 0x8d, 0x96,
-	0x00, 0x00, 0xff, 0xff, 0x6c, 0xee, 0x68, 0x81, 0xf8, 0x01, 0x00, 0x00,
+	0xcd, 0x5c, 0xbd, 0x0e, 0xa5, 0x6e, 0x7e, 0x5e, 0x2d, 0x67, 0xfb, 0x66, 0x3d, 0xf7, 0x9b, 0x9b,
+	0x6d, 0x8b, 0xbc, 0x6d, 0x5b, 0xe4, 0x63, 0xdb, 0x22, 0x0f, 0xae, 0xf6, 0x17, 0xd3, 0xa9, 0x6b,
+	0x5e, 0xc0, 0xd5, 0x67, 0x00, 0x00, 0x00, 0xff, 0xff, 0x99, 0xf3, 0x92, 0x3d, 0x32, 0x02, 0x00,
+	0x00,
 }

prompb/types.proto

@@ -49,3 +49,8 @@ message LabelMatcher {
   string name  = 2;
   string value = 3;
 }
+
+message ReadHints {
+  int64 step_ms = 1; // Query step size in milliseconds.
+  string func = 2;   // String representation of surrounding function or aggregation.
+}

storage/remote/codec.go

@@ -86,16 +86,22 @@ func ToWriteRequest(samples []*model.Sample) *prompb.WriteRequest {
 }
 
 // ToQuery builds a Query proto.
-func ToQuery(from, to int64, matchers []*labels.Matcher) (*prompb.Query, error) {
+func ToQuery(from, to int64, matchers []*labels.Matcher, p *storage.SelectParams) (*prompb.Query, error) {
 	ms, err := toLabelMatchers(matchers)
 	if err != nil {
 		return nil, err
 	}
 
+	rp := &prompb.ReadHints{
+		StepMs: p.Step,
+		Func:   p.Func,
+	}
+
 	return &prompb.Query{
 		StartTimestampMs: from,
 		EndTimestampMs:   to,
 		Matchers:         ms,
+		Hints:            rp,
 	}, nil
 }
 

storage/remote/read.go

@@ -43,8 +43,8 @@ type querier struct {
 
 // Select implements storage.Querier and uses the given matchers to read series
 // sets from the Client.
-func (q *querier) Select(_ *storage.SelectParams, matchers ...*labels.Matcher) (storage.SeriesSet, error) {
+func (q *querier) Select(p *storage.SelectParams, matchers ...*labels.Matcher) (storage.SeriesSet, error) {
-	query, err := ToQuery(q.mint, q.maxt, matchers)
+	query, err := ToQuery(q.mint, q.maxt, matchers, p)
 	if err != nil {
 		return nil, err
 	}

web/api/v1/api_test.go

@@ -40,6 +40,7 @@ import (
 	"github.com/prometheus/prometheus/prompb"
 	"github.com/prometheus/prometheus/promql"
 	"github.com/prometheus/prometheus/scrape"
+	"github.com/prometheus/prometheus/storage"
 	"github.com/prometheus/prometheus/storage/remote"
 )
 
@@ -588,7 +589,7 @@ func TestReadEndpoint(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	query, err := remote.ToQuery(0, 1, []*labels.Matcher{matcher1, matcher2})
+	query, err := remote.ToQuery(0, 1, []*labels.Matcher{matcher1, matcher2}, &storage.SelectParams{Step: 0, Func: "avg"})
 	if err != nil {
 		t.Fatal(err)
 	}