loki/pkg/querier/queryrange/codec_test.go

package queryrange

import (
	"bytes"
	"context"
	"errors"
	"fmt"
	"io"
	"net/http"
	"net/http/httptest"
	"net/url"
	"strconv"
	"strings"
	"testing"
	"time"

	"github.com/axiomhq/hyperloglog"
	"github.com/gorilla/mux"
	"github.com/grafana/dskit/user"
	"github.com/prometheus/common/model"
	"github.com/prometheus/prometheus/model/labels"
	"github.com/prometheus/prometheus/model/timestamp"
	"github.com/prometheus/prometheus/promql"
	"github.com/prometheus/prometheus/promql/parser"
	"github.com/stretchr/testify/require"
	"go.opentelemetry.io/otel/attribute"
	tracesdk "go.opentelemetry.io/otel/sdk/trace"
	"go.opentelemetry.io/otel/sdk/trace/tracetest"

	"github.com/grafana/loki/v3/pkg/loghttp"
	"github.com/grafana/loki/v3/pkg/logproto"
	"github.com/grafana/loki/v3/pkg/logql"
	"github.com/grafana/loki/v3/pkg/logql/syntax"
	"github.com/grafana/loki/v3/pkg/logqlmodel"
	"github.com/grafana/loki/v3/pkg/logqlmodel/stats"
	"github.com/grafana/loki/v3/pkg/querier/plan"
	"github.com/grafana/loki/v3/pkg/querier/queryrange/queryrangebase"
	"github.com/grafana/loki/v3/pkg/util"
	"github.com/grafana/loki/v3/pkg/util/httpreq"
)

func init() {
	time.Local = nil // for easier tests comparison
}

var (
	start = testTime //  Marshalling the time drops the monotonic clock so we can't use time.Now
	end   = start.Add(1 * time.Hour)
)

func Test_codec_EncodeDecodeRequest(t *testing.T) {
	ctx := user.InjectOrgID(context.Background(), "1")

	tests := []struct {
		name       string
		reqBuilder func() (*http.Request, error)
		want       queryrangebase.Request
		wantErr    bool
	}{
		{"wrong", func() (*http.Request, error) { return http.NewRequest(http.MethodGet, "/bad?step=bad", nil) }, nil, true},
		{"query_range", func() (*http.Request, error) {
			return http.NewRequest(http.MethodGet,
				fmt.Sprintf(`/query_range?start=%d&end=%d&query={foo="bar"}&step=10&limit=200&direction=FORWARD`, start.UnixNano(), end.UnixNano()), nil)
		}, &LokiRequest{
			Query:     `{foo="bar"}`,
			Limit:     200,
			Step:      10000, // step is expected in ms
			Direction: logproto.FORWARD,
			Path:      "/query_range",
			StartTs:   start,
			EndTs:     end,
			Plan: &plan.QueryPlan{
				AST: syntax.MustParseExpr(`{foo="bar"}`),
			},
		}, false},
		{"query_range", func() (*http.Request, error) {
			return http.NewRequest(http.MethodGet,
				fmt.Sprintf(`/query_range?start=%d&end=%d&query={foo="bar"}&interval=10&limit=200&direction=BACKWARD`, start.UnixNano(), end.UnixNano()), nil)
		}, &LokiRequest{
			Query:     `{foo="bar"}`,
			Limit:     200,
			Step:      14000, // step is expected in ms; calculated default if request param not present
			Interval:  10000, // interval is expected in ms
			Direction: logproto.BACKWARD,
			Path:      "/query_range",
			StartTs:   start,
			EndTs:     end,
			Plan: &plan.QueryPlan{
				AST: syntax.MustParseExpr(`{foo="bar"}`),
			},
		}, false},
		{"legacy query_range with refexp", func() (*http.Request, error) {
			return http.NewRequest(http.MethodGet,
				fmt.Sprintf(`/api/prom/query?start=%d&end=%d&query={foo="bar"}&interval=10&limit=200&direction=BACKWARD&regexp=foo`, start.UnixNano(), end.UnixNano()), nil)
		}, &LokiRequest{
			Query:     `{foo="bar"} |~ "foo"`,
			Limit:     200,
			Step:      14000, // step is expected in ms; calculated default if request param not present
			Interval:  10000, // interval is expected in ms
			Direction: logproto.BACKWARD,
			Path:      "/api/prom/query",
			StartTs:   start,
			EndTs:     end,
			Plan: &plan.QueryPlan{
				AST: syntax.MustParseExpr(`{foo="bar"} |~ "foo"`),
			},
		}, false},
		{"series", func() (*http.Request, error) {
			return http.NewRequest(http.MethodGet,
				fmt.Sprintf(`/series?start=%d&end=%d&match={foo="bar"}`, start.UnixNano(), end.UnixNano()), nil)
		}, &LokiSeriesRequest{
			Match:   []string{`{foo="bar"}`},
			Path:    "/series",
			StartTs: start,
			EndTs:   end,
		}, false},
		{
			"labels", func() (*http.Request, error) {
				return http.NewRequest(http.MethodGet,
					fmt.Sprintf(`/loki/api/v1/labels?start=%d&end=%d&query={foo="bar"}`, start.UnixNano(), end.UnixNano()), nil)
			}, NewLabelRequest(start, end, `{foo="bar"}`, "", "/loki/api/v1/labels"),
			false,
		},
		{
			"label_values", func() (*http.Request, error) {
				req, err := http.NewRequest(http.MethodGet,
					fmt.Sprintf(`/loki/api/v1/label/test/values?start=%d&end=%d&query={foo="bar"}`, start.UnixNano(), end.UnixNano()), nil)
				req = mux.SetURLVars(req, map[string]string{"name": "test"})
				return req, err
			}, NewLabelRequest(start, end, `{foo="bar"}`, "test", "/loki/api/v1/label/test/values"),
			false,
		},
		{"index_stats", func() (*http.Request, error) {
			return DefaultCodec.EncodeRequest(ctx, &logproto.IndexStatsRequest{
				From:     model.TimeFromUnixNano(start.UnixNano()),
				Through:  model.TimeFromUnixNano(end.UnixNano()),
				Matchers: `{job="foo"}`,
			})
		}, &logproto.IndexStatsRequest{
			From:     model.TimeFromUnixNano(start.UnixNano()),
			Through:  model.TimeFromUnixNano(end.UnixNano()),
			Matchers: `{job="foo"}`,
		}, false},
		{"volume", func() (*http.Request, error) {
			return DefaultCodec.EncodeRequest(ctx, &logproto.VolumeRequest{
				From:         model.TimeFromUnixNano(start.UnixNano()),
				Through:      model.TimeFromUnixNano(end.UnixNano()),
				Matchers:     `{job="foo"}`,
				Limit:        3,
				Step:         0,
				TargetLabels: []string{"job"},
				AggregateBy:  "labels",
			})
		}, &logproto.VolumeRequest{
			From:         model.TimeFromUnixNano(start.UnixNano()),
			Through:      model.TimeFromUnixNano(end.UnixNano()),
			Matchers:     `{job="foo"}`,
			Limit:        3,
			Step:         0,
			TargetLabels: []string{"job"},
			AggregateBy:  "labels",
		}, false},
		{"volume_default_limit", func() (*http.Request, error) {
			return DefaultCodec.EncodeRequest(ctx, &logproto.VolumeRequest{
				From:     model.TimeFromUnixNano(start.UnixNano()),
				Through:  model.TimeFromUnixNano(end.UnixNano()),
				Matchers: `{job="foo"}`,
			})
		}, &logproto.VolumeRequest{
			From:        model.TimeFromUnixNano(start.UnixNano()),
			Through:     model.TimeFromUnixNano(end.UnixNano()),
			Matchers:    `{job="foo"}`,
			Limit:       100,
			Step:        0,
			AggregateBy: "series",
		}, false},
		{"volume_range", func() (*http.Request, error) {
			return DefaultCodec.EncodeRequest(ctx, &logproto.VolumeRequest{
				From:         model.TimeFromUnixNano(start.UnixNano()),
				Through:      model.TimeFromUnixNano(end.UnixNano()),
				Matchers:     `{job="foo"}`,
				Limit:        3,
				Step:         30 * 1e3,
				TargetLabels: []string{"fizz", "buzz"},
			})
		}, &logproto.VolumeRequest{
			From:         model.TimeFromUnixNano(start.UnixNano()),
			Through:      model.TimeFromUnixNano(end.UnixNano()),
			Matchers:     `{job="foo"}`,
			Limit:        3,
			Step:         30 * 1e3, // step is expected in ms
			TargetLabels: []string{"fizz", "buzz"},
			AggregateBy:  "series",
		}, false},
		{"volume_range_default_limit", func() (*http.Request, error) {
			return DefaultCodec.EncodeRequest(ctx, &logproto.VolumeRequest{
				From:     model.TimeFromUnixNano(start.UnixNano()),
				Through:  model.TimeFromUnixNano(end.UnixNano()),
				Matchers: `{job="foo"}`,
				Step:     30 * 1e3, // step is expected in ms
			})
		}, &logproto.VolumeRequest{
			From:        model.TimeFromUnixNano(start.UnixNano()),
			Through:     model.TimeFromUnixNano(end.UnixNano()),
			Matchers:    `{job="foo"}`,
			Limit:       100,
			Step:        30 * 1e3, // step is expected in ms; default is 0 or no step
			AggregateBy: "series",
		}, false},
		{"detected_fields", func() (*http.Request, error) {
			return DefaultCodec.EncodeRequest(ctx, &DetectedFieldsRequest{
				logproto.DetectedFieldsRequest{
					Query:     `{foo="bar"}`,
					Start:     start,
					End:       end,
					Step:      30 * 1e3, // step is expected in ms; default is 0 or no step
					LineLimit: 100,
					Limit:     100,
				},
				"/loki/api/v1/detected_fields",
			})
		}, &DetectedFieldsRequest{
			logproto.DetectedFieldsRequest{
				Query:     `{foo="bar"}`,
				Start:     start,
				End:       end,
				Step:      30 * 1e3, // step is expected in ms; default is 0 or no step
				LineLimit: 100,
				Limit:     100,
			},
			"/loki/api/v1/detected_fields",
		}, false},
		{"detected field values", func() (*http.Request, error) {
			req, err := DefaultCodec.EncodeRequest(ctx, &DetectedFieldsRequest{
				logproto.DetectedFieldsRequest{
					Query:     `{baz="bar"}`,
					Start:     start,
					End:       end,
					Step:      30 * 1e3, // step is expected in ms; default is 0 or no step
					LineLimit: 100,
					Limit:     100,
				},
				"/loki/api/v1/detected_field/foo/values",
			})
			if err != nil {
				return nil, err
			}

			req = mux.SetURLVars(req, map[string]string{"name": "foo"})
			return req, nil
		}, &DetectedFieldsRequest{
			logproto.DetectedFieldsRequest{
				Query:     `{baz="bar"}`,
				Start:     start,
				End:       end,
				Step:      30 * 1e3, // step is expected in ms; default is 0 or no step
				LineLimit: 100,
				Limit:     100,
				Values:    true,
				Name:      "foo",
			},
			"/loki/api/v1/detected_field/foo/values",
		}, false},
		{"patterns", func() (*http.Request, error) {
			return DefaultCodec.EncodeRequest(ctx, &logproto.QueryPatternsRequest{
				Start: start,
				End:   end,
				Step:  30 * 1e3, // step is expected in ms
			})
		}, &logproto.QueryPatternsRequest{
			Start: start,
			End:   end,
			Step:  30 * 1e3, // step is expected in ms; default is 0 or no step
		}, false},
		{"detected_labels", func() (*http.Request, error) {
			return DefaultCodec.EncodeRequest(ctx, &DetectedLabelsRequest{
				"/loki/api/v1/detected_labels",
				logproto.DetectedLabelsRequest{
					Query: `{foo="bar"}`,
					Start: start,
					End:   end,
				},
			})
		}, &DetectedLabelsRequest{
			"/loki/api/v1/detected_labels",
			logproto.DetectedLabelsRequest{
				Query: `{foo="bar"}`,
				Start: start,
				End:   end,
			},
		}, false},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			req, err := tt.reqBuilder()
			if err != nil {
				t.Fatal(err)
			}
			got, err := DefaultCodec.DecodeRequest(context.TODO(), req, nil)
			if (err != nil) != tt.wantErr {
				t.Errorf("codec.DecodeRequest() error = %v, wantErr %v", err, tt.wantErr)
				return
			}
			require.Equal(t, tt.want, got)
		})
	}
}

func Test_codec_DecodeRequest_cacheHeader(t *testing.T) {
	ctx := user.InjectOrgID(context.Background(), "1")

	tests := []struct {
		name       string
		reqBuilder func() (*http.Request, error)
		want       queryrangebase.Request
	}{
		{
			"query_instant",
			func() (*http.Request, error) {
				req, err := http.NewRequest(
					http.MethodGet,
					fmt.Sprintf(`/v1/query?time=%d&query={foo="bar"}&limit=200&direction=FORWARD`, start.UnixNano()),
					nil,
				)
				if err == nil {
					req.Header.Set(cacheControlHeader, noCacheVal)
				}
				return req, err
			},
			&LokiInstantRequest{
				Query:     `{foo="bar"}`,
				Limit:     200,
				Direction: logproto.FORWARD,
				Path:      "/v1/query",
				TimeTs:    start,
				Plan: &plan.QueryPlan{
					AST: syntax.MustParseExpr(`{foo="bar"}`),
				},
				CachingOptions: queryrangebase.CachingOptions{
					Disabled: true,
				},
			},
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			req, err := tt.reqBuilder()
			if err != nil {
				t.Fatal(err)
			}
			got, err := DefaultCodec.DecodeRequest(ctx, req, nil)
			require.NoError(t, err)
			require.Equal(t, tt.want, got)
		})
	}
}

func Test_codec_DecodeResponse(t *testing.T) {
	tests := []struct {
		name    string
		res     *http.Response
		req     queryrangebase.Request
		want    queryrangebase.Response
		wantErr string
	}{
		{"500", &http.Response{StatusCode: 500, Body: io.NopCloser(strings.NewReader("some error"))}, nil, nil, "some error"},
		{"no body", &http.Response{StatusCode: 200, Body: io.NopCloser(badReader{})}, nil, nil, "error decoding response"},
		{"bad json", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(""))}, nil, nil, "Value looks like object, but can't find closing"},
		{"not success", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(`{"status":"fail"}`))}, nil, nil, "unsupported response type"},
		{"unknown", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(`{"status":"success"}`))}, nil, nil, "unsupported response type"},
		{
			"matrix", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(matrixString))}, nil,
			&LokiPromResponse{
				Response: &queryrangebase.PrometheusResponse{
					Status: loghttp.QueryStatusSuccess,
					Data: queryrangebase.PrometheusData{
						ResultType: loghttp.ResultTypeMatrix,
						Result:     sampleStreams,
					},
				},
				Statistics: statsResult,
			}, "",
		},
		{
			"matrix-empty-streams",
			&http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(matrixStringEmptyResult))},
			nil,
			&LokiPromResponse{
				Response: &queryrangebase.PrometheusResponse{
					Status: loghttp.QueryStatusSuccess,
					Data: queryrangebase.PrometheusData{
						ResultType: loghttp.ResultTypeMatrix,
						Result:     make([]queryrangebase.SampleStream, 0), // shouldn't be nil.
					},
				},
				Statistics: statsResult,
			}, "",
		},
		{
			"vector-empty-streams",
			&http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(vectorStringEmptyResult))},
			nil,
			&LokiPromResponse{
				Response: &queryrangebase.PrometheusResponse{
					Status: loghttp.QueryStatusSuccess,
					Data: queryrangebase.PrometheusData{
						ResultType: loghttp.ResultTypeVector,
						Result:     make([]queryrangebase.SampleStream, 0), // shouldn't be nil.
					},
				},
				Statistics: statsResult,
			}, "",
		},
		{
			"streams v1", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(streamsString))},
			&LokiRequest{Direction: logproto.FORWARD, Limit: 100, Path: "/loki/api/v1/query_range"},
			&LokiResponse{
				Status:    loghttp.QueryStatusSuccess,
				Direction: logproto.FORWARD,
				Limit:     100,
				Version:   uint32(loghttp.VersionV1),
				Data: LokiData{
					ResultType: loghttp.ResultTypeStream,
					Result:     logStreams,
				},
				Statistics: statsResult,
			}, "",
		},
		{
			"streams v1 with structured metadata", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(streamsStringWithStructuredMetdata))},
			&LokiRequest{Direction: logproto.FORWARD, Limit: 100, Path: "/loki/api/v1/query_range"},
			&LokiResponse{
				Status:    loghttp.QueryStatusSuccess,
				Direction: logproto.FORWARD,
				Limit:     100,
				Version:   uint32(loghttp.VersionV1),
				Data: LokiData{
					ResultType: loghttp.ResultTypeStream,
					Result:     logStreamsWithStructuredMetadata,
				},
				Statistics: statsResult,
			}, "",
		},
		{
			"streams v1 with categorized labels", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(streamsStringWithCategories))},
			&LokiRequest{Direction: logproto.FORWARD, Limit: 100, Path: "/loki/api/v1/query_range"},
			&LokiResponse{
				Status:    loghttp.QueryStatusSuccess,
				Direction: logproto.FORWARD,
				Limit:     100,
				Version:   uint32(loghttp.VersionV1),
				Data: LokiData{
					ResultType: loghttp.ResultTypeStream,
					Result:     logStreamsWithCategories,
				},
				Statistics: statsResult,
			}, "",
		},
		{
			"streams legacy", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(streamsString))},
			&LokiRequest{Direction: logproto.FORWARD, Limit: 100, Path: "/api/prom/query_range"},
			&LokiResponse{
				Status:    loghttp.QueryStatusSuccess,
				Direction: logproto.FORWARD,
				Limit:     100,
				Version:   uint32(loghttp.VersionLegacy),
				Data: LokiData{
					ResultType: loghttp.ResultTypeStream,
					Result:     logStreams,
				},
				Statistics: statsResult,
			}, "",
		},
		{
			"series", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(seriesString))},
			&LokiSeriesRequest{Path: "/loki/api/v1/series"},
			&LokiSeriesResponse{
				Status:  "success",
				Version: uint32(loghttp.VersionV1),
				Data:    seriesData,
			}, "",
		},
		{
			"labels legacy", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(labelsString))},
			NewLabelRequest(time.Now(), time.Now(), "", "", "/api/prom/label"),
			&LokiLabelNamesResponse{
				Status:  "success",
				Version: uint32(loghttp.VersionLegacy),
				Data:    labelsData,
			}, "",
		},
		{
			"index stats", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(indexStatsString))},
			&logproto.IndexStatsRequest{},
			&IndexStatsResponse{
				Response: &logproto.IndexStatsResponse{
					Streams: 1,
					Chunks:  2,
					Bytes:   3,
					Entries: 4,
				},
			}, "",
		},
		{
			"volume", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(seriesVolumeString))},
			&logproto.VolumeRequest{},
			&VolumeResponse{
				Response: &logproto.VolumeResponse{
					Volumes: []logproto.Volume{
						{Name: `{foo="bar"}`, Volume: 38},
					},
					Limit: 100,
				},
			}, "",
		},
		{
			"series error", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(`{"status":"success","data":"not an array"}`))},
			&LokiSeriesRequest{Path: "/loki/api/v1/series"},
			nil, "Value is array",
		},
		{
			"series error wrong status type", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(`{"status":42}`))},
			&LokiSeriesRequest{Path: "/loki/api/v1/series"},
			nil, "Value is not a string",
		},
		{
			"series error no object", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(`{"status":"success","data": ["not an object"]}`))},
			&LokiSeriesRequest{Path: "/loki/api/v1/series"},
			nil, "unexpected data type: got(string), expected (object)",
		},
		{
			"series error wrong value type", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(`{"status":"success","data": [{"some": 42}]}`))},
			&LokiSeriesRequest{Path: "/loki/api/v1/series"},
			nil, "unexpected label value type: got(number), expected (string)",
		},
		{
			"series error wrong key type", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(`{"status":"success","data": [{42: "some string"}]}`))},
			&LokiSeriesRequest{Path: "/loki/api/v1/series"},
			nil, "error decoding response: invalid character",
		},
		{
			"series error key decode", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(`{"status":"success","data": [{"\x": "some string"}]}`))},
			&LokiSeriesRequest{Path: "/loki/api/v1/series"},
			nil, "invalid character 'x' in string escape code",
		},
		{
			"series error value decode", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(`{"status":"success","data": [{"label": "some string\x"}]}`))},
			&LokiSeriesRequest{Path: "/loki/api/v1/series"},
			nil, "invalid character 'x' in string escape code",
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got, err := DefaultCodec.DecodeResponse(context.TODO(), tt.res, tt.req)
			if tt.wantErr != "" {
				require.ErrorContains(t, err, tt.wantErr)
				return
			}

			require.NoError(t, err)
			require.Equal(t, tt.want, got)
		})
	}
}

func TestLokiRequestSpanLogging(t *testing.T) {
	now := time.Now()
	end := now.Add(1000 * time.Second)
	req := LokiRequest{
		StartTs: now,
		EndTs:   end,
	}

	exporter := tracetest.NewInMemoryExporter()
	tp := tracesdk.NewTracerProvider(
		tracesdk.WithSpanProcessor(tracesdk.NewSimpleSpanProcessor(exporter)),
	)
	_, sp := tp.Tracer("test").Start(context.Background(), "request")
	req.LogToSpan(sp)
	sp.End()

	spans := exporter.GetSpans()
	require.Len(t, spans, 1)
	span := spans[0]
	found := 0
	for _, l := range span.Attributes {
		if l.Key == "start" {
			require.Equal(t, attribute.StringValue(timestamp.Time(now.UnixMilli()).String()), l.Value)
			found++
		}
		if l.Key == "end" {
			require.Equal(t, attribute.StringValue(timestamp.Time(end.UnixMilli()).String()), l.Value)
			found++
		}
	}
	require.Equal(t, 2, found, "expected to find start and end attributes in span")
}

func TestLokiInstantRequestSpanLogging(t *testing.T) {
	now := time.Now()
	req := LokiInstantRequest{
		TimeTs: now,
	}

	exporter := tracetest.NewInMemoryExporter()
	tp := tracesdk.NewTracerProvider(
		tracesdk.WithSpanProcessor(tracesdk.NewSimpleSpanProcessor(exporter)),
	)
	_, sp := tp.Tracer("test").Start(context.Background(), "request")
	req.LogToSpan(sp)
	sp.End()

	spans := exporter.GetSpans()
	require.Len(t, spans, 1)
	span := spans[0]
	found := 0
	for _, l := range span.Attributes {
		if l.Key == "ts" {
			require.Equal(t, attribute.StringValue(timestamp.Time(now.UnixMilli()).String()), l.Value)
			found++
		}
	}
	require.Equal(t, 1, found, "expected to find ts attribute in span")
}

func TestLokiSeriesRequestSpanLogging(t *testing.T) {
	now := time.Now()
	end := now.Add(1000 * time.Second)
	req := LokiSeriesRequest{
		StartTs: now,
		EndTs:   end,
	}

	exporter := tracetest.NewInMemoryExporter()
	tp := tracesdk.NewTracerProvider(
		tracesdk.WithSpanProcessor(tracesdk.NewSimpleSpanProcessor(exporter)),
	)
	_, sp := tp.Tracer("test").Start(context.Background(), "request")
	req.LogToSpan(sp)
	sp.End()

	spans := exporter.GetSpans()
	require.Len(t, spans, 1)
	span := spans[0]
	found := 0
	for _, l := range span.Attributes {
		if l.Key == "start" {
			require.Equal(t, attribute.StringValue(timestamp.Time(now.UnixMilli()).String()), l.Value)
			found++
		}
		if l.Key == "end" {
			require.Equal(t, attribute.StringValue(timestamp.Time(end.UnixMilli()).String()), l.Value)
			found++
		}
	}
	require.Equal(t, 2, found, "expected to find start and end attributes in span")
}

func TestLabelRequestSpanLogging(t *testing.T) {
	now := time.Now()
	end := now.Add(1000 * time.Second)
	req := LabelRequest{
		LabelRequest: logproto.LabelRequest{
			Start: &now,
			End:   &end,
		},
	}

	exporter := tracetest.NewInMemoryExporter()
	tp := tracesdk.NewTracerProvider(
		tracesdk.WithSpanProcessor(tracesdk.NewSimpleSpanProcessor(exporter)),
	)
	_, sp := tp.Tracer("test").Start(context.Background(), "request")
	req.LogToSpan(sp)
	sp.End()

	spans := exporter.GetSpans()
	require.Len(t, spans, 1)
	span := spans[0]
	found := 0
	for _, l := range span.Attributes {
		if l.Key == "start" {
			require.Equal(t, attribute.StringValue(timestamp.Time(now.UnixMilli()).String()), l.Value)
			found++
		}
		if l.Key == "end" {
			require.Equal(t, attribute.StringValue(timestamp.Time(end.UnixMilli()).String()), l.Value)
			found++
		}
	}
	require.Equal(t, 2, found, "expected to find start and end attributes in span")
}

func Test_codec_DecodeProtobufResponseParity(t *testing.T) {
	// test fixtures from pkg/util/marshal_test
	queryTests := []struct {
		name     string
		actual   parser.Value
		expected string
	}{
		{
			"basic",
			logqlmodel.Streams{
				logproto.Stream{
					Entries: []logproto.Entry{
						{
							Timestamp: time.Unix(0, 123456789012345),
							Line:      "super line",
						},
					},
					Labels: `{test="test"}`,
				},
			},
			`{
				"status": "success",
				"data": {
					` + statsResultString + `
					"resultType": "streams",
					"result": [
						{
							"stream": {
								"test": "test"
							},
							"values":[
								[ "123456789012345", "super line" ]
							]
						}
					]
				}
			}`,
		},
		// vector test
		{
			"vector",
			promql.Vector{
				{
					T: 1568404331324,
					F: 0.013333333333333334,
					Metric: labels.FromStrings(
						"filename", `/var/hostlog/apport.log`,
						"job", "varlogs",
					),
				},
				{
					T: 1568404331324,
					F: 3.45,
					Metric: labels.FromStrings(
						"filename", `/var/hostlog/syslog`,
						"job", "varlogs",
					),
				},
			},
			`{
				"data": {
					` + statsResultString + `
					"resultType": "vector",
					"result": [
						{
						"metric": {
							"filename": "\/var\/hostlog\/apport.log",
							"job": "varlogs"
						},
						"value": [
							1568404331.324,
							"0.013333333333333334"
						]
						},
						{
						"metric": {
							"filename": "\/var\/hostlog\/syslog",
							"job": "varlogs"
						},
						"value": [
							1568404331.324,
							"3.45"
							]
						}
					]
				},
				"status": "success"
			}`,
		},
		// matrix test
		{
			"matrix",
			promql.Matrix{
				{
					Floats: []promql.FPoint{
						{
							T: 1568404331324,
							F: 0.013333333333333334,
						},
					},
					Metric: labels.FromStrings(
						"filename", `/var/hostlog/apport.log`,
						"job", "varlogs",
					),
				},
				{
					Floats: []promql.FPoint{
						{
							T: 1568404331324,
							F: 3.45,
						},
						{
							T: 1568404331339,
							F: 4.45,
						},
					},
					Metric: labels.FromStrings(
						"filename", `/var/hostlog/syslog`,
						"job", "varlogs",
					),
				},
			},
			`{
				"data": {
					` + statsResultString + `
					"resultType": "matrix",
					"result": [
						{
						"metric": {
							"filename": "\/var\/hostlog\/apport.log",
							"job": "varlogs"
						},
						"values": [
							[
								1568404331.324,
								"0.013333333333333334"
							]
							]
						},
						{
						"metric": {
							"filename": "\/var\/hostlog\/syslog",
							"job": "varlogs"
						},
						"values": [
								[
									1568404331.324,
									"3.45"
								],
								[
									1568404331.339,
									"4.45"
								]
							]
						}
					]
				},
				"status": "success"
			}`,
		},
	}
	codec := RequestProtobufCodec{}
	for i, queryTest := range queryTests {
		t.Run(queryTest.name, func(t *testing.T) {
			params := url.Values{
				"query": []string{`{app="foo"}`},
			}
			u := &url.URL{
				Path:     "/loki/api/v1/query_range",
				RawQuery: params.Encode(),
			}
			httpReq := &http.Request{
				Method:     "GET",
				RequestURI: u.String(),
				URL:        u,
			}
			req, err := codec.DecodeRequest(context.TODO(), httpReq, nil)
			require.NoError(t, err)

			// parser.Value -> queryrange.QueryResponse
			var b bytes.Buffer
			result := logqlmodel.Result{
				Data:       queryTest.actual,
				Statistics: statsResult,
			}
			err = WriteQueryResponseProtobuf(&logql.LiteralParams{}, result, &b)
			require.NoError(t, err)

			// queryrange.QueryResponse -> queryrangebase.Response
			querierResp := &http.Response{
				StatusCode: 200,
				Body:       io.NopCloser(&b),
				Header: http.Header{
					"Content-Type": []string{ProtobufType},
				},
			}
			resp, err := codec.DecodeResponse(context.TODO(), querierResp, req)
			require.NoError(t, err)

			// queryrange.Response -> JSON
			ctx := user.InjectOrgID(context.Background(), "1")
			httpResp, err := codec.EncodeResponse(ctx, httpReq, resp)
			require.NoError(t, err)

			body, err := io.ReadAll(httpResp.Body)
			require.NoError(t, err)
			require.JSONEqf(t, queryTest.expected, string(body), "Protobuf Decode Query Test %d failed", i)
		})
	}
}

func Test_codec_EncodeRequest(t *testing.T) {
	// we only accept LokiRequest.
	ctx := user.InjectOrgID(context.Background(), "1")
	got, err := DefaultCodec.EncodeRequest(ctx, &queryrangebase.PrometheusRequest{})
	require.Error(t, err)
	require.Nil(t, got)

	toEncode := &LokiRequest{
		Query:     `{foo="bar"}`,
		Limit:     200,
		Step:      86400000, // nanoseconds
		Interval:  10000000, // nanoseconds
		Direction: logproto.FORWARD,
		Path:      "/query_range",
		StartTs:   start,
		EndTs:     end,
	}
	got, err = DefaultCodec.EncodeRequest(ctx, toEncode)
	require.NoError(t, err)
	require.Equal(t, ctx, got.Context())
	require.Equal(t, "/loki/api/v1/query_range", got.URL.Path)
	require.Equal(t, fmt.Sprintf("%d", start.UnixNano()), got.URL.Query().Get("start"))
	require.Equal(t, fmt.Sprintf("%d", end.UnixNano()), got.URL.Query().Get("end"))
	require.Equal(t, `{foo="bar"}`, got.URL.Query().Get("query"))
	require.Equal(t, fmt.Sprintf("%d", 200), got.URL.Query().Get("limit"))
	require.Equal(t, `FORWARD`, got.URL.Query().Get("direction"))
	require.Equal(t, "86400.000000", got.URL.Query().Get("step"))
	require.Equal(t, "10000.000000", got.URL.Query().Get("interval"))

	// testing a full roundtrip
	req, err := DefaultCodec.DecodeRequest(context.TODO(), got, nil)
	require.NoError(t, err)
	require.Equal(t, toEncode.Query, req.(*LokiRequest).Query)
	require.Equal(t, toEncode.Step, req.(*LokiRequest).Step)
	require.Equal(t, toEncode.Interval, req.(*LokiRequest).Interval)
	require.Equal(t, toEncode.StartTs, req.(*LokiRequest).StartTs)
	require.Equal(t, toEncode.EndTs, req.(*LokiRequest).EndTs)
	require.Equal(t, toEncode.Direction, req.(*LokiRequest).Direction)
	require.Equal(t, toEncode.Limit, req.(*LokiRequest).Limit)
	require.Equal(t, "/loki/api/v1/query_range", req.(*LokiRequest).Path)
}

func Test_codec_series_EncodeRequest(t *testing.T) {
	ctx := user.InjectOrgID(context.Background(), "1")
	got, err := DefaultCodec.EncodeRequest(ctx, &queryrangebase.PrometheusRequest{})
	require.Error(t, err)
	require.Nil(t, got)

	toEncode := &LokiSeriesRequest{
		Match:   []string{`{foo="bar"}`},
		Path:    "/series",
		StartTs: start,
		EndTs:   end,
	}
	got, err = DefaultCodec.EncodeRequest(ctx, toEncode)
	require.NoError(t, err)
	require.Equal(t, ctx, got.Context())
	require.Equal(t, "/loki/api/v1/series", got.URL.Path)
	require.Equal(t, fmt.Sprintf("%d", start.UnixNano()), got.URL.Query().Get("start"))
	require.Equal(t, fmt.Sprintf("%d", end.UnixNano()), got.URL.Query().Get("end"))
	require.Equal(t, `{foo="bar"}`, got.URL.Query().Get("match[]"))

	// testing a full roundtrip
	req, err := DefaultCodec.DecodeRequest(context.TODO(), got, nil)
	require.NoError(t, err)
	require.Equal(t, toEncode.Match, req.(*LokiSeriesRequest).Match)
	require.Equal(t, toEncode.StartTs, req.(*LokiSeriesRequest).StartTs)
	require.Equal(t, toEncode.EndTs, req.(*LokiSeriesRequest).EndTs)
	require.Equal(t, "/loki/api/v1/series", req.(*LokiSeriesRequest).Path)
}

func Test_codec_labels_EncodeRequest(t *testing.T) {
	ctx := user.InjectOrgID(context.Background(), "1")

	// Test labels endpoint
	toEncode := NewLabelRequest(start, end, `{foo="bar"}`, "", "/loki/api/v1/labels")
	got, err := DefaultCodec.EncodeRequest(ctx, toEncode)
	require.NoError(t, err)
	require.Equal(t, ctx, got.Context())
	require.Equal(t, "/loki/api/v1/labels", got.URL.Path)
	require.Equal(t, fmt.Sprintf("%d", start.UnixNano()), got.URL.Query().Get("start"))
	require.Equal(t, fmt.Sprintf("%d", end.UnixNano()), got.URL.Query().Get("end"))
	require.Equal(t, `{foo="bar"}`, got.URL.Query().Get("query"))

	// testing a full roundtrip
	req, err := DefaultCodec.DecodeRequest(context.TODO(), got, nil)
	require.NoError(t, err)
	require.Equal(t, toEncode.Start, req.(*LabelRequest).Start)
	require.Equal(t, toEncode.End, req.(*LabelRequest).End)
	require.Equal(t, toEncode.Query, req.(*LabelRequest).Query)
	require.Equal(t, "/loki/api/v1/labels", req.(*LabelRequest).Path())

	// Test label values endpoint
	toEncode = NewLabelRequest(start, end, `{foo="bar"}`, "__name__", "/loki/api/v1/label/__name__/values")
	got, err = DefaultCodec.EncodeRequest(ctx, toEncode)
	require.NoError(t, err)
	require.Equal(t, ctx, got.Context())
	require.Equal(t, "/loki/api/v1/label/__name__/values", got.URL.Path)
	require.Equal(t, fmt.Sprintf("%d", start.UnixNano()), got.URL.Query().Get("start"))
	require.Equal(t, fmt.Sprintf("%d", end.UnixNano()), got.URL.Query().Get("end"))
	require.Equal(t, `{foo="bar"}`, got.URL.Query().Get("query"))

	// testing a full roundtrip
	got = mux.SetURLVars(got, map[string]string{"name": "__name__"})
	req, err = DefaultCodec.DecodeRequest(context.TODO(), got, nil)
	require.NoError(t, err)
	require.Equal(t, toEncode.Start, req.(*LabelRequest).Start)
	require.Equal(t, toEncode.End, req.(*LabelRequest).End)
	require.Equal(t, toEncode.Query, req.(*LabelRequest).Query)
	require.Equal(t, "/loki/api/v1/label/__name__/values", req.(*LabelRequest).Path())
}

func Test_codec_labels_DecodeRequest(t *testing.T) {
	ctx := user.InjectOrgID(context.Background(), "1")

	// Test labels endpoint
	u, err := url.Parse(`/loki/api/v1/labels?start=1575285010000000010&end=1575288610000000010&query={foo="bar"}`)
	require.NoError(t, err)

	r := &http.Request{URL: u}
	req, err := DefaultCodec.DecodeRequest(context.TODO(), r, nil)
	require.NoError(t, err)
	require.Equal(t, start, *req.(*LabelRequest).Start)
	require.Equal(t, end, *req.(*LabelRequest).End)
	require.Equal(t, `{foo="bar"}`, req.(*LabelRequest).Query)
	require.Equal(t, "/loki/api/v1/labels", req.(*LabelRequest).Path())

	got, err := DefaultCodec.EncodeRequest(ctx, req)
	require.NoError(t, err)
	require.Equal(t, ctx, got.Context())
	require.Equal(t, "/loki/api/v1/labels", got.URL.Path)
	require.Equal(t, fmt.Sprintf("%d", start.UnixNano()), got.URL.Query().Get("start"))
	require.Equal(t, fmt.Sprintf("%d", end.UnixNano()), got.URL.Query().Get("end"))
	require.Equal(t, `{foo="bar"}`, got.URL.Query().Get("query"))

	// Test label values endpoint
	u, err = url.Parse(`/loki/api/v1/label/__name__/values?start=1575285010000000010&end=1575288610000000010&query={foo="bar"}`)
	require.NoError(t, err)

	r = &http.Request{URL: u}
	r = mux.SetURLVars(r, map[string]string{"name": "__name__"})
	req, err = DefaultCodec.DecodeRequest(context.TODO(), r, nil)
	require.NoError(t, err)
	require.Equal(t, start, *req.(*LabelRequest).Start)
	require.Equal(t, end, *req.(*LabelRequest).End)
	require.Equal(t, `{foo="bar"}`, req.(*LabelRequest).Query)
	require.Equal(t, "/loki/api/v1/label/__name__/values", req.(*LabelRequest).Path())

	got, err = DefaultCodec.EncodeRequest(ctx, req)
	require.NoError(t, err)
	require.Equal(t, ctx, got.Context())
	require.Equal(t, "/loki/api/v1/label/__name__/values", got.URL.Path)
	require.Equal(t, fmt.Sprintf("%d", start.UnixNano()), got.URL.Query().Get("start"))
	require.Equal(t, fmt.Sprintf("%d", end.UnixNano()), got.URL.Query().Get("end"))
	require.Equal(t, `{foo="bar"}`, got.URL.Query().Get("query"))
}

func Test_codec_index_stats_EncodeRequest(t *testing.T) {
	from, through := util.RoundToMilliseconds(start, end)
	toEncode := &logproto.IndexStatsRequest{
		From:     from,
		Through:  through,
		Matchers: `{job="foo"}`,
	}
	ctx := user.InjectOrgID(context.Background(), "1")
	got, err := DefaultCodec.EncodeRequest(ctx, toEncode)
	require.Nil(t, err)
	require.Equal(t, fmt.Sprintf("%d", from.UnixNano()), got.URL.Query().Get("start"))
	require.Equal(t, fmt.Sprintf("%d", through.UnixNano()), got.URL.Query().Get("end"))
	require.Equal(t, `{job="foo"}`, got.URL.Query().Get("query"))
}

func Test_codec_seriesVolume_EncodeRequest(t *testing.T) {
	from, through := util.RoundToMilliseconds(start, end)
	toEncode := &logproto.VolumeRequest{
		From:         from,
		Through:      through,
		Matchers:     `{job="foo"}`,
		Limit:        20,
		Step:         30 * 1e6,
		TargetLabels: []string{"foo", "bar"},
	}
	ctx := user.InjectOrgID(context.Background(), "1")
	got, err := DefaultCodec.EncodeRequest(ctx, toEncode)
	require.Nil(t, err)
	require.Equal(t, fmt.Sprintf("%d", from.UnixNano()), got.URL.Query().Get("start"))
	require.Equal(t, fmt.Sprintf("%d", through.UnixNano()), got.URL.Query().Get("end"))
	require.Equal(t, `{job="foo"}`, got.URL.Query().Get("query"))
	require.Equal(t, "20", got.URL.Query().Get("limit"))
	require.Equal(t, fmt.Sprintf("%f", float64(toEncode.Step/1e3)), got.URL.Query().Get("step"))
	require.Equal(t, `foo,bar`, got.URL.Query().Get("targetLabels"))
}

func Test_codec_seriesVolume_DecodeRequest(t *testing.T) {
	ctx := user.InjectOrgID(context.Background(), "1")
	t.Run("instant queries set a step of 0", func(t *testing.T) {
		req := httptest.NewRequest(http.MethodGet, "/loki/api/v1/index/volume"+
			"?start=0"+
			"&end=1"+
			"&step=42"+
			"&query=%7Bfoo%3D%22bar%22%7D", nil)
		got, err := DefaultCodec.DecodeRequest(ctx, req, nil)
		require.NoError(t, err)

		require.Equal(t, int64(0), got.(*logproto.VolumeRequest).Step)
	})

	t.Run("range queries parse step from request", func(t *testing.T) {
		req := httptest.NewRequest(http.MethodGet, "/loki/api/v1/index/volume_range"+
			"?start=0"+
			"&end=1"+
			"&step=42"+
			"&query=%7Bfoo%3D%22bar%22%7D", nil)
		got, err := DefaultCodec.DecodeRequest(ctx, req, nil)
		require.NoError(t, err)

		require.Equal(t, (42 * time.Second).Milliseconds(), got.(*logproto.VolumeRequest).Step)
	})

	t.Run("range queries provide default step when not provided", func(t *testing.T) {
		req := httptest.NewRequest(http.MethodGet, "/loki/api/v1/index/volume_range"+
			"?start=0"+
			"&end=1"+
			"&query=%7Bfoo%3D%22bar%22%7D", nil)
		got, err := DefaultCodec.DecodeRequest(ctx, req, nil)
		require.NoError(t, err)

		require.Equal(t, time.Second.Milliseconds(), got.(*logproto.VolumeRequest).Step)
	})
}

func Test_codec_EncodeResponse(t *testing.T) {
	tests := []struct {
		name        string
		path        string
		res         queryrangebase.Response
		body        string
		wantErr     bool
		queryParams map[string]string
	}{
		{"error", "/loki/api/v1/query_range", &badResponse{}, "", true, nil},
		{
			"prom", "/loki/api/v1/query_range",
			&LokiPromResponse{
				Response: &queryrangebase.PrometheusResponse{
					Status: loghttp.QueryStatusSuccess,
					Data: queryrangebase.PrometheusData{
						ResultType: loghttp.ResultTypeMatrix,
						Result:     sampleStreams,
					},
				},
				Statistics: statsResult,
			}, matrixString, false, nil,
		},
		{
			"loki v1", "/loki/api/v1/query_range",
			&LokiResponse{
				Status:    loghttp.QueryStatusSuccess,
				Direction: logproto.FORWARD,
				Limit:     100,
				Version:   uint32(loghttp.VersionV1),
				Data: LokiData{
					ResultType: loghttp.ResultTypeStream,
					Result:     logStreams,
				},
				Statistics: statsResult,
			}, streamsString, false, nil,
		},
		{
			"loki v1 with categories", "/loki/api/v1/query_range",
			&LokiResponse{
				Status:    loghttp.QueryStatusSuccess,
				Direction: logproto.FORWARD,
				Limit:     100,
				Version:   uint32(loghttp.VersionV1),
				Data: LokiData{
					ResultType: loghttp.ResultTypeStream,
					Result:     logStreamsWithCategories,
				},
				Statistics: statsResult,
			},
			streamsStringWithCategories, false,
			map[string]string{
				httpreq.LokiEncodingFlagsHeader: string(httpreq.FlagCategorizeLabels),
			},
		},
		{
			"loki legacy", "/api/promt/query",
			&LokiResponse{
				Status:    loghttp.QueryStatusSuccess,
				Direction: logproto.FORWARD,
				Limit:     100,
				Version:   uint32(loghttp.VersionLegacy),
				Data: LokiData{
					ResultType: loghttp.ResultTypeStream,
					Result:     logStreams,
				},
				Statistics: statsResult,
			}, streamsStringLegacy, false, nil,
		},
		{
			"loki series", "/loki/api/v1/series",
			&LokiSeriesResponse{
				Status:  "success",
				Version: uint32(loghttp.VersionV1),
				Data:    seriesData,
			}, seriesString, false, nil,
		},
		{
			"loki labels", "/loki/api/v1/labels",
			&LokiLabelNamesResponse{
				Status:  "success",
				Version: uint32(loghttp.VersionV1),
				Data:    labelsData,
			}, labelsString, false, nil,
		},
		{
			"loki labels legacy", "/api/prom/label",
			&LokiLabelNamesResponse{
				Status:  "success",
				Version: uint32(loghttp.VersionLegacy),
				Data:    labelsData,
			}, labelsLegacyString, false, nil,
		},
		{
			"index stats", "/loki/api/v1/index/stats",
			&IndexStatsResponse{
				Response: &logproto.IndexStatsResponse{
					Streams: 1,
					Chunks:  2,
					Bytes:   3,
					Entries: 4,
				},
			}, indexStatsString, false, nil,
		},
		{
			"volume", "/loki/api/v1/index/volume",
			&VolumeResponse{
				Response: &logproto.VolumeResponse{
					Volumes: []logproto.Volume{
						{Name: `{foo="bar"}`, Volume: 38},
					},
					Limit: 100,
				},
			}, seriesVolumeString, false, nil,
		},
		{
			"empty matrix", "/loki/api/v1/query_range",
			&LokiPromResponse{
				Response: &queryrangebase.PrometheusResponse{
					Status: loghttp.QueryStatusSuccess,
					Data: queryrangebase.PrometheusData{
						ResultType: loghttp.ResultTypeMatrix,
						Result:     nil,
					},
				},
				Statistics: statsResult,
			},
			`{
				"data": {
				  ` + statsResultString + `
	              "resultType": "matrix",
	              "result": []
	            },
	            "status": "success"
		     }`,
			false, nil,
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			u := &url.URL{Path: tt.path}
			h := http.Header{}
			for k, v := range tt.queryParams {
				h.Set(k, v)
			}
			req := &http.Request{
				Method:     "GET",
				RequestURI: u.String(),
				URL:        u,
				Header:     h,
			}
			ctx := user.InjectOrgID(context.Background(), "1")
			got, err := DefaultCodec.EncodeResponse(ctx, req, tt.res)
			if (err != nil) != tt.wantErr {
				t.Errorf("codec.EncodeResponse() error = %v, wantErr %v", err, tt.wantErr)
				return
			}
			if err == nil {
				require.Equal(t, 200, got.StatusCode)
				body, err := io.ReadAll(got.Body)
				require.Nil(t, err)
				bodyString := string(body)
				require.JSONEq(t, tt.body, bodyString)
			}
		})
	}
}

func Test_codec_MergeResponse(t *testing.T) {
	tests := []struct {
		name         string
		responses    []queryrangebase.Response
		want         queryrangebase.Response
		errorMessage string
	}{
		{
			"empty",
			[]queryrangebase.Response{},
			nil,
			"merging responses requires at least one response",
		},
		{
			"unknown response",
			[]queryrangebase.Response{&badResponse{}},
			nil,
			"unknown response type (*queryrange.badResponse) in merging responses",
		},
		{
			"prom",
			[]queryrangebase.Response{
				&LokiPromResponse{
					Response: &queryrangebase.PrometheusResponse{
						Status: loghttp.QueryStatusSuccess,
						Data: queryrangebase.PrometheusData{
							ResultType: loghttp.ResultTypeMatrix,
							Result:     sampleStreams,
						},
					},
				},
			},
			&LokiPromResponse{
				Statistics: stats.Result{Summary: stats.Summary{Splits: 1}},
				Response: &queryrangebase.PrometheusResponse{
					Status: loghttp.QueryStatusSuccess,
					Data: queryrangebase.PrometheusData{
						ResultType: loghttp.ResultTypeMatrix,
						Result:     sampleStreams,
					},
				},
			},
			"",
		},
		{
			"loki backward",
			[]queryrangebase.Response{
				&LokiResponse{
					Status:    loghttp.QueryStatusSuccess,
					Warnings:  []string{"warning"},
					Direction: logproto.BACKWARD,
					Limit:     100,
					Version:   1,
					Data: LokiData{
						ResultType: loghttp.ResultTypeStream,
						Result: []logproto.Stream{
							{
								Labels: `{foo="bar", level="error"}`,
								Entries: []logproto.Entry{
									{Timestamp: time.Unix(0, 2), Line: "2"},
									{Timestamp: time.Unix(0, 1), Line: "1"},
								},
							},
							{
								Labels: `{foo="bar", level="debug"}`,
								Entries: []logproto.Entry{
									{Timestamp: time.Unix(0, 6), Line: "6"},
									{Timestamp: time.Unix(0, 5), Line: "5"},
								},
							},
						},
					},
				},
				&LokiResponse{
					Status:    loghttp.QueryStatusSuccess,
					Direction: logproto.BACKWARD,
					Limit:     100,
					Version:   1,
					Data: LokiData{
						ResultType: loghttp.ResultTypeStream,
						Result: []logproto.Stream{
							{
								Labels: `{foo="bar", level="error"}`,
								Entries: []logproto.Entry{
									{Timestamp: time.Unix(0, 10), Line: "10"},
									{Timestamp: time.Unix(0, 9), Line: "9"},
									{Timestamp: time.Unix(0, 9), Line: "9"},
								},
							},
							{
								Labels: `{foo="bar", level="debug"}`,
								Entries: []logproto.Entry{
									{Timestamp: time.Unix(0, 16), Line: "16"},
									{Timestamp: time.Unix(0, 15), Line: "15"},
								},
							},
						},
					},
				},
			},
			&LokiResponse{
				Status:     loghttp.QueryStatusSuccess,
				Warnings:   []string{"warning"},
				Direction:  logproto.BACKWARD,
				Limit:      100,
				Version:    1,
				Statistics: stats.Result{Summary: stats.Summary{Splits: 2}},
				Data: LokiData{
					ResultType: loghttp.ResultTypeStream,
					Result: []logproto.Stream{
						{
							Labels: `{foo="bar", level="error"}`,
							Entries: []logproto.Entry{
								{Timestamp: time.Unix(0, 10), Line: "10"},
								{Timestamp: time.Unix(0, 9), Line: "9"},
								{Timestamp: time.Unix(0, 9), Line: "9"},
								{Timestamp: time.Unix(0, 2), Line: "2"},
								{Timestamp: time.Unix(0, 1), Line: "1"},
							},
						},
						{
							Labels: `{foo="bar", level="debug"}`,
							Entries: []logproto.Entry{
								{Timestamp: time.Unix(0, 16), Line: "16"},
								{Timestamp: time.Unix(0, 15), Line: "15"},
								{Timestamp: time.Unix(0, 6), Line: "6"},
								{Timestamp: time.Unix(0, 5), Line: "5"},
							},
						},
					},
				},
			},
			"",
		},
		{
			"loki backward limited",
			[]queryrangebase.Response{
				&LokiResponse{
					Status:    loghttp.QueryStatusSuccess,
					Direction: logproto.BACKWARD,
					Limit:     6,
					Version:   1,
					Data: LokiData{
						ResultType: loghttp.ResultTypeStream,
						Result: []logproto.Stream{
							{
								Labels: `{foo="bar", level="error"}`,
								Entries: []logproto.Entry{
									{Timestamp: time.Unix(0, 10), Line: "10"},
									{Timestamp: time.Unix(0, 9), Line: "9"},
									{Timestamp: time.Unix(0, 9), Line: "9"},
								},
							},
							{
								Labels: `{foo="bar", level="debug"}`,
								Entries: []logproto.Entry{
									{Timestamp: time.Unix(0, 16), Line: "16"},
									{Timestamp: time.Unix(0, 15), Line: "15"},
								},
							},
						},
					},
				},
				&LokiResponse{
					Status:    loghttp.QueryStatusSuccess,
					Direction: logproto.BACKWARD,
					Limit:     6,
					Version:   1,
					Data: LokiData{
						ResultType: loghttp.ResultTypeStream,
						Result: []logproto.Stream{
							{
								Labels: `{foo="bar", level="error"}`,
								Entries: []logproto.Entry{
									{Timestamp: time.Unix(0, 2), Line: "2"},
									{Timestamp: time.Unix(0, 1), Line: "1"},
								},
							},
							{
								Labels: `{foo="bar", level="debug"}`,
								Entries: []logproto.Entry{
									{Timestamp: time.Unix(0, 6), Line: "6"},
									{Timestamp: time.Unix(0, 5), Line: "5"},
								},
							},
						},
					},
				},
			},
			&LokiResponse{
				Status:     loghttp.QueryStatusSuccess,
				Direction:  logproto.BACKWARD,
				Limit:      6,
				Version:    1,
				Statistics: stats.Result{Summary: stats.Summary{Splits: 2}},
				Data: LokiData{
					ResultType: loghttp.ResultTypeStream,
					Result: []logproto.Stream{
						{
							Labels: `{foo="bar", level="error"}`,
							Entries: []logproto.Entry{
								{Timestamp: time.Unix(0, 10), Line: "10"},
								{Timestamp: time.Unix(0, 9), Line: "9"},
								{Timestamp: time.Unix(0, 9), Line: "9"},
							},
						},
						{
							Labels: `{foo="bar", level="debug"}`,
							Entries: []logproto.Entry{
								{Timestamp: time.Unix(0, 16), Line: "16"},
								{Timestamp: time.Unix(0, 15), Line: "15"},
								{Timestamp: time.Unix(0, 6), Line: "6"},
							},
						},
					},
				},
			},
			"",
		},
		{
			"loki forward",
			[]queryrangebase.Response{
				&LokiResponse{
					Status:    loghttp.QueryStatusSuccess,
					Direction: logproto.FORWARD,
					Limit:     100,
					Version:   1,
					Data: LokiData{
						ResultType: loghttp.ResultTypeStream,
						Result: []logproto.Stream{
							{
								Labels: `{foo="bar", level="error"}`,
								Entries: []logproto.Entry{
									{Timestamp: time.Unix(0, 1), Line: "1"},
									{Timestamp: time.Unix(0, 2), Line: "2"},
								},
							},
							{
								Labels: `{foo="bar", level="debug"}`,
								Entries: []logproto.Entry{
									{Timestamp: time.Unix(0, 5), Line: "5"},
									{Timestamp: time.Unix(0, 6), Line: "6"},
								},
							},
						},
					},
				},
				&LokiResponse{
					Status:    loghttp.QueryStatusSuccess,
					Direction: logproto.FORWARD,
					Limit:     100,
					Version:   1,
					Data: LokiData{
						ResultType: loghttp.ResultTypeStream,
						Result: []logproto.Stream{
							{
								Labels: `{foo="bar", level="error"}`,
								Entries: []logproto.Entry{
									{Timestamp: time.Unix(0, 9), Line: "9"},
									{Timestamp: time.Unix(0, 10), Line: "10"},
								},
							},
							{
								Labels: `{foo="bar", level="debug"}`,
								Entries: []logproto.Entry{
									{Timestamp: time.Unix(0, 15), Line: "15"},
									{Timestamp: time.Unix(0, 15), Line: "15"},
									{Timestamp: time.Unix(0, 16), Line: "16"},
								},
							},
						},
					},
				},
			},
			&LokiResponse{
				Status:     loghttp.QueryStatusSuccess,
				Direction:  logproto.FORWARD,
				Limit:      100,
				Version:    1,
				Statistics: stats.Result{Summary: stats.Summary{Splits: 2}},
				Data: LokiData{
					ResultType: loghttp.ResultTypeStream,
					Result: []logproto.Stream{
						{
							Labels: `{foo="bar", level="debug"}`,
							Entries: []logproto.Entry{
								{Timestamp: time.Unix(0, 5), Line: "5"},
								{Timestamp: time.Unix(0, 6), Line: "6"},
								{Timestamp: time.Unix(0, 15), Line: "15"},
								{Timestamp: time.Unix(0, 15), Line: "15"},
								{Timestamp: time.Unix(0, 16), Line: "16"},
							},
						},
						{
							Labels: `{foo="bar", level="error"}`,
							Entries: []logproto.Entry{
								{Timestamp: time.Unix(0, 1), Line: "1"},
								{Timestamp: time.Unix(0, 2), Line: "2"},
								{Timestamp: time.Unix(0, 9), Line: "9"},
								{Timestamp: time.Unix(0, 10), Line: "10"},
							},
						},
					},
				},
			},
			"",
		},
		{
			"loki forward limited",
			[]queryrangebase.Response{
				&LokiResponse{
					Status:    loghttp.QueryStatusSuccess,
					Direction: logproto.FORWARD,
					Limit:     5,
					Version:   1,
					Data: LokiData{
						ResultType: loghttp.ResultTypeStream,
						Result: []logproto.Stream{
							{
								Labels: `{foo="bar", level="error"}`,
								Entries: []logproto.Entry{
									{Timestamp: time.Unix(0, 1), Line: "1"},
									{Timestamp: time.Unix(0, 2), Line: "2"},
								},
							},
							{
								Labels: `{foo="bar", level="debug"}`,
								Entries: []logproto.Entry{
									{Timestamp: time.Unix(0, 5), Line: "5"},
									{Timestamp: time.Unix(0, 6), Line: "6"},
								},
							},
						},
					},
				},
				&LokiResponse{
					Status:    loghttp.QueryStatusSuccess,
					Direction: logproto.FORWARD,
					Limit:     5,
					Version:   1,
					Data: LokiData{
						ResultType: loghttp.ResultTypeStream,
						Result: []logproto.Stream{
							{
								Labels: `{foo="bar", level="error"}`,
								Entries: []logproto.Entry{
									{Timestamp: time.Unix(0, 9), Line: "9"},
									{Timestamp: time.Unix(0, 10), Line: "10"},
								},
							},
							{
								Labels: `{foo="bar", level="debug"}`,
								Entries: []logproto.Entry{
									{Timestamp: time.Unix(0, 15), Line: "15"},
									{Timestamp: time.Unix(0, 15), Line: "15"},
									{Timestamp: time.Unix(0, 16), Line: "16"},
								},
							},
						},
					},
				},
			},
			&LokiResponse{
				Status:     loghttp.QueryStatusSuccess,
				Direction:  logproto.FORWARD,
				Limit:      5,
				Version:    1,
				Statistics: stats.Result{Summary: stats.Summary{Splits: 2}},
				Data: LokiData{
					ResultType: loghttp.ResultTypeStream,
					Result: []logproto.Stream{
						{
							Labels: `{foo="bar", level="debug"}`,
							Entries: []logproto.Entry{
								{Timestamp: time.Unix(0, 5), Line: "5"},
								{Timestamp: time.Unix(0, 6), Line: "6"},
							},
						},
						{
							Labels: `{foo="bar", level="error"}`,
							Entries: []logproto.Entry{
								{Timestamp: time.Unix(0, 1), Line: "1"},
								{Timestamp: time.Unix(0, 2), Line: "2"},
								{Timestamp: time.Unix(0, 9), Line: "9"},
							},
						},
					},
				},
			},
			"",
		},
		{
			"loki series",
			[]queryrangebase.Response{
				&LokiSeriesResponse{
					Status:  "success",
					Version: 1,
					Data: []logproto.SeriesIdentifier{
						{
							Labels: []logproto.SeriesIdentifier_LabelsEntry{
								{Key: "filename", Value: "/var/hostlog/apport.log"},
								{Key: "job", Value: "varlogs"},
							},
						},
						{
							Labels: []logproto.SeriesIdentifier_LabelsEntry{
								{Key: "filename", Value: "/var/hostlog/test.log"},
								{Key: "job", Value: "varlogs"},
							},
						},
					},
				},
				&LokiSeriesResponse{
					Status:  "success",
					Version: 1,
					Data: []logproto.SeriesIdentifier{
						{
							Labels: []logproto.SeriesIdentifier_LabelsEntry{
								{Key: "filename", Value: "/var/hostlog/apport.log"},
								{Key: "job", Value: "varlogs"},
							},
						},
						{
							Labels: []logproto.SeriesIdentifier_LabelsEntry{
								{Key: "filename", Value: "/var/hostlog/other.log"},
								{Key: "job", Value: "varlogs"},
							},
						},
					},
				},
			},
			&LokiSeriesResponse{
				Statistics: stats.Result{Summary: stats.Summary{Splits: 2}},
				Status:     "success",
				Version:    1,
				Data: []logproto.SeriesIdentifier{
					{
						Labels: []logproto.SeriesIdentifier_LabelsEntry{
							{Key: "filename", Value: "/var/hostlog/apport.log"},
							{Key: "job", Value: "varlogs"},
						},
					},
					{
						Labels: []logproto.SeriesIdentifier_LabelsEntry{
							{Key: "filename", Value: "/var/hostlog/test.log"},
							{Key: "job", Value: "varlogs"},
						},
					},
					{
						Labels: []logproto.SeriesIdentifier_LabelsEntry{
							{Key: "filename", Value: "/var/hostlog/other.log"},
							{Key: "job", Value: "varlogs"},
						},
					},
				},
			},
			"",
		},
		{
			"loki labels",
			[]queryrangebase.Response{
				&LokiLabelNamesResponse{
					Status:  "success",
					Version: 1,
					Data:    []string{"foo", "bar", "buzz"},
				},
				&LokiLabelNamesResponse{
					Status:  "success",
					Version: 1,
					Data:    []string{"foo", "bar", "buzz"},
				},
				&LokiLabelNamesResponse{
					Status:  "success",
					Version: 1,
					Data:    []string{"foo", "blip", "blop"},
				},
			},
			&LokiLabelNamesResponse{
				Statistics: stats.Result{Summary: stats.Summary{Splits: 3}},
				Status:     "success",
				Version:    1,
				Data:       []string{"foo", "bar", "buzz", "blip", "blop"},
			},
			"",
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got, err := DefaultCodec.MergeResponse(tt.responses...)
			if tt.errorMessage != "" {
				require.ErrorContains(t, err, tt.errorMessage)
			}
			require.Equal(t, tt.want, got)
		})
	}
}

func Test_codec_MergeResponse_DetectedFieldsResponse(t *testing.T) {
	buildDetctedField := func(label string, cardinality uint64) *logproto.DetectedField {
		fooSketch := hyperloglog.New()

		for i := 0; i < int(cardinality); i++ {
			fooSketch.Insert([]byte(fmt.Sprintf("value %d", i)))
		}
		marshalledSketch, err := fooSketch.MarshalBinary()
		require.NoError(t, err)

		return &logproto.DetectedField{
			Label:       label,
			Type:        logproto.DetectedFieldString,
			Cardinality: cardinality,
			Sketch:      marshalledSketch,
		}
	}

	t.Run("merges the responses", func(t *testing.T) {
		responses := []queryrangebase.Response{
			&DetectedFieldsResponse{
				Response: &logproto.DetectedFieldsResponse{
					Fields: []*logproto.DetectedField{
						buildDetctedField("foo", 1),
					},
					Limit: 2,
				},
			},
			&DetectedFieldsResponse{
				Response: &logproto.DetectedFieldsResponse{
					Fields: []*logproto.DetectedField{
						buildDetctedField("foo", 3),
					},
					Limit: 2,
				},
			},
		}

		got, err := DefaultCodec.MergeResponse(responses...)
		require.Nil(t, err)
		response := got.(*DetectedFieldsResponse).Response
		require.Equal(t, 1, len(response.Fields))

		foo := response.Fields[0]
		require.Equal(t, foo.Label, "foo")
		require.Equal(t, foo.Type, logproto.DetectedFieldString)
		require.Equal(t, foo.Cardinality, uint64(3))
	})

	t.Run("merges the responses, enforcing the limit", func(t *testing.T) {
		responses := []queryrangebase.Response{
			&DetectedFieldsResponse{
				Response: &logproto.DetectedFieldsResponse{
					Fields: []*logproto.DetectedField{
						buildDetctedField("foo", 1),
						buildDetctedField("bar", 42),
					},
					Limit: 2,
				},
			},
			&DetectedFieldsResponse{
				Response: &logproto.DetectedFieldsResponse{
					Fields: []*logproto.DetectedField{
						buildDetctedField("foo", 27),
						buildDetctedField("baz", 3),
					},
					Limit: 2,
				},
			},
		}

		got, err := DefaultCodec.MergeResponse(responses...)
		require.Nil(t, err)
		response := got.(*DetectedFieldsResponse).Response
		require.Equal(t, 2, len(response.Fields))

		var foo *logproto.DetectedField
		var baz *logproto.DetectedField
		for _, f := range response.Fields {
			if f.Label == "foo" {
				foo = f
			}
			if f.Label == "baz" {
				baz = f
			}
		}

		require.Equal(t, foo.Label, "foo")
		require.Equal(t, foo.Type, logproto.DetectedFieldString)
		require.Equal(t, 27, int(foo.Cardinality))

		require.Nil(t, baz)
	})
}

type badResponse struct{}

func (badResponse) Reset()                                                 {}
func (badResponse) String() string                                         { return "noop" }
func (badResponse) ProtoMessage()                                          {}
func (badResponse) GetHeaders() []*queryrangebase.PrometheusResponseHeader { return nil }
func (b badResponse) WithHeaders([]queryrangebase.PrometheusResponseHeader) queryrangebase.Response {
	return b
}
func (badResponse) SetHeader(string, string) {}

type badReader struct{}

func (badReader) Read(_ []byte) (n int, err error) {
	return 0, errors.New("")
}

var (
	statsResultString = `"stats" : {
		"ingester" : {
			"store": {
				"chunk":{
					"compressedBytes": 1,
					"decompressedBytes": 2,
					"decompressedLines": 3,
					"decompressedStructuredMetadataBytes": 0,
					"headChunkBytes": 4,
					"headChunkLines": 5,
					"headChunkStructuredMetadataBytes": 0,
					"postFilterLines": 0,
					"totalDuplicates": 8
				},
				"chunksDownloadTime": 0,
				"congestionControlLatency": 0,
				"dataobj":{
					"pageBatches": 0,
					"pagesDownloaded": 0,
					"pagesDownloadedBytes": 0,
					"pagesScanned": 0,
					"postFilterRows": 0,
					"postPredicateRows": 0,
					"postPredicateDecompressedBytes": 0,
					"postPredicateStructuredMetadataBytes": 0,
					"prePredicateDecompressedRows": 0,
					"prePredicateDecompressedBytes": 0,
					"prePredicateDecompressedStructuredMetadataBytes": 0,
					"totalPageDownloadTime": 0,
					"totalRowsAvailable": 0
				},
				"totalChunksRef": 0,
				"totalChunksDownloaded": 0,
				"chunkRefsFetchTime": 0,
				"queryReferencedStructuredMetadata": false,
				"queryUsedV2Engine": false,
				"pipelineWrapperFilteredLines": 2
			},
			"totalBatches": 6,
			"totalChunksMatched": 7,
			"totalLinesSent": 9,
			"totalReached": 10
		},
		"querier": {
			"store" : {
				"chunk": {
					"compressedBytes": 11,
					"decompressedBytes": 12,
					"decompressedLines": 13,
					"decompressedStructuredMetadataBytes": 0,
					"headChunkBytes": 14,
					"headChunkLines": 15,
					"headChunkStructuredMetadataBytes": 0,
                    "postFilterLines": 0,
					"totalDuplicates": 19
				},
				"chunksDownloadTime": 16,
				"congestionControlLatency": 0,
				"dataobj":{
					"pageBatches": 0,
					"pagesDownloaded": 0,
					"pagesDownloadedBytes": 0,
					"pagesScanned": 0,
					"postFilterRows": 0,
					"postPredicateRows": 0,
					"postPredicateDecompressedBytes": 0,
					"postPredicateStructuredMetadataBytes": 0,
					"prePredicateDecompressedRows": 0,
					"prePredicateDecompressedBytes": 0,
					"prePredicateDecompressedStructuredMetadataBytes": 0,
					"totalPageDownloadTime": 0,
					"totalRowsAvailable": 0
				},
				"totalChunksRef": 17,
				"totalChunksDownloaded": 18,
				"chunkRefsFetchTime": 19,
				"queryReferencedStructuredMetadata": true,
				"queryUsedV2Engine": false,
				"pipelineWrapperFilteredLines": 4
			}
		},
		"index": {
			"postFilterChunks": 0,
			"totalChunks": 0,
			"shardsDuration": 0,
			"usedBloomFilters": false
		},
		"cache": {
			"chunk": {
				"entriesFound": 0,
				"entriesRequested": 0,
				"entriesStored": 0,
				"bytesReceived": 0,
				"bytesSent": 0,
				"requests": 0,
				"downloadTime": 0,
				"queryLengthServed": 0
			},
			"index": {
				"entriesFound": 0,
				"entriesRequested": 0,
				"entriesStored": 0,
				"bytesReceived": 0,
				"bytesSent": 0,
				"requests": 0,
				"downloadTime": 0,
				"queryLengthServed": 0
			},
		  "statsResult": {
				"entriesFound": 0,
				"entriesRequested": 0,
				"entriesStored": 0,
				"bytesReceived": 0,
				"bytesSent": 0,
				"requests": 0,
				"downloadTime": 0,
				"queryLengthServed": 0
			},
		  "seriesResult": {
				"entriesFound": 0,
				"entriesRequested": 0,
				"entriesStored": 0,
				"bytesReceived": 0,
				"bytesSent": 0,
				"requests": 0,
				"downloadTime": 0,
				"queryLengthServed": 0
			},
		  "labelResult": {
				"entriesFound": 0,
				"entriesRequested": 0,
				"entriesStored": 0,
				"bytesReceived": 0,
				"bytesSent": 0,
				"requests": 0,
				"downloadTime": 0,
				"queryLengthServed": 0
			},
		  "volumeResult": {
				"entriesFound": 0,
				"entriesRequested": 0,
				"entriesStored": 0,
				"bytesReceived": 0,
				"bytesSent": 0,
				"requests": 0,
				"downloadTime": 0,
				"queryLengthServed": 0
			},
		  "instantMetricResult": {
				"entriesFound": 0,
				"entriesRequested": 0,
				"entriesStored": 0,
				"bytesReceived": 0,
				"bytesSent": 0,
				"requests": 0,
				"downloadTime": 0,
				"queryLengthServed": 0
			},
			"result": {
				"entriesFound": 0,
				"entriesRequested": 0,
				"entriesStored": 0,
				"bytesReceived": 0,
				"bytesSent": 0,
				"requests": 0,
				"downloadTime": 0,
				"queryLengthServed": 0
			}
		},
		"summary": {
			"bytesProcessedPerSecond": 20,
			"execTime": 22,
			"linesProcessedPerSecond": 23,
			"queueTime": 21,
			"shards": 0,
			"splits": 0,
			"subqueries": 0,
			"totalBytesProcessed": 24,
			"totalEntriesReturned": 10,
			"totalLinesProcessed": 25,
			"totalStructuredMetadataBytesProcessed": 0,
            "totalPostFilterLines": 0
		}
	},`
	matrixString = `{
	"data": {
	  ` + statsResultString + `
	  "resultType": "matrix",
	  "result": [
		{
		  "metric": {
			"filename": "\/var\/hostlog\/apport.log",
			"job": "varlogs"
		  },
		  "values": [
			  [
				1568404331.324,
				"0.013333333333333334"
			  ]
			]
		},
		{
		  "metric": {
			"filename": "\/var\/hostlog\/syslog",
			"job": "varlogs"
		  },
		  "values": [
				[
					1568404331.324,
					"3.45"
				],
				[
					1568404331.339,
					"4.45"
				]
			]
		}
	  ]
	},
	"status": "success"
  }`
	matrixStringEmptyResult = `{
	"data": {
	  ` + statsResultString + `
	  "resultType": "matrix",
	  "result": []
	},
	"status": "success"
  }`
	vectorStringEmptyResult = `{
	"data": {
	  ` + statsResultString + `
	  "resultType": "vector",
	  "result": []
	},
	"status": "success"
  }`

	sampleStreams = []queryrangebase.SampleStream{
		{
			Labels:  []logproto.LabelAdapter{{Name: "filename", Value: "/var/hostlog/apport.log"}, {Name: "job", Value: "varlogs"}},
			Samples: []logproto.LegacySample{{Value: 0.013333333333333334, TimestampMs: 1568404331324}},
		},
		{
			Labels:  []logproto.LabelAdapter{{Name: "filename", Value: "/var/hostlog/syslog"}, {Name: "job", Value: "varlogs"}},
			Samples: []logproto.LegacySample{{Value: 3.45, TimestampMs: 1568404331324}, {Value: 4.45, TimestampMs: 1568404331339}},
		},
	}
	streamsString = `{
		"status": "success",
		"data": {
			` + statsResultString + `
			"resultType": "streams",
			"result": [
				{
					"stream": {
						"test": "test"
					},
					"values":[
						[ "123456789012345", "super line"]
					]
				},
				{
					"stream": {
						"test": "test",
                        "x": "a",
                        "y": "b"
					},
					"values":[
						[ "123456789012346", "super line2" ]
					]
				},
				{
					"stream": {
						"test": "test",
                        "x": "a",
                        "y": "b",
						"z": "text"
					},
					"values":[
						[ "123456789012346", "super line3 z=text" ]
					]
				}
			]
		}
	}`
	streamsStringWithStructuredMetdata = `{
		"status": "success",
		"data": {
			` + statsResultString + `
			"resultType": "streams",
			"result": [
				{
					"stream": {
						"test": "test"
					},
					"values":[
						[ "123456789012345", "super line"]
					]
				},
				{
					"stream": {
						"test": "test",
                        "x": "a",
                        "y": "b"
					},
					"values":[
						[ "123456789012346", "super line2", {"x": "a", "y": "b"} ]
					]
				},
				{
					"stream": {
						"test": "test",
                        "x": "a",
                        "y": "b",
						"z": "text"
					},
					"values":[
						[ "123456789012346", "super line3 z=text", {"x": "a", "y": "b"}]
					]
				}
			]
		}
	}`
	streamsStringWithCategories = `{
		"status": "success",
		"data": {
			` + statsResultString + `
			"resultType": "streams",
			"encodingFlags": ["` + string(httpreq.FlagCategorizeLabels) + `"],
			"result": [
				{
					"stream": {
						"test": "test"
					},
					"values":[
						[ "123456789012345", "super line", {}],
						[ "123456789012346", "super line2", {
							"structuredMetadata": {
								"x": "a",
								"y": "b"
							}
						}],
						[ "123456789012347", "super line3 z=text", {
							"structuredMetadata": {
								"x": "a",
								"y": "b"
							},
							"parsed": {
								"z": "text"
							}
						}]
					]
				}
			]
		}
	}`
	streamsStringLegacy = `{
		` + statsResultString + `"streams":[{"labels":"{test=\"test\"}","entries":[{"ts":"1970-01-02T10:17:36.789012345Z","line":"super line"}]},{"labels":"{test=\"test\", x=\"a\", y=\"b\"}","entries":[{"ts":"1970-01-02T10:17:36.789012346Z","line":"super line2"}]}, {"labels":"{test=\"test\", x=\"a\", y=\"b\", z=\"text\"}","entries":[{"ts":"1970-01-02T10:17:36.789012346Z","line":"super line3 z=text"}]}]}`
	logStreamsWithStructuredMetadata = []logproto.Stream{
		{
			Labels: `{test="test"}`,
			Entries: []logproto.Entry{
				{
					Line:      "super line",
					Timestamp: time.Unix(0, 123456789012345).UTC(),
				},
			},
		},
		{
			Labels: `{test="test", x="a", y="b"}`,
			Entries: []logproto.Entry{
				{
					Line:               "super line2",
					Timestamp:          time.Unix(0, 123456789012346).UTC(),
					StructuredMetadata: logproto.FromLabelsToLabelAdapters(labels.FromStrings("x", "a", "y", "b")),
				},
			},
		},
		{
			Labels: `{test="test", x="a", y="b", z="text"}`,
			Entries: []logproto.Entry{
				{
					Line:               "super line3 z=text",
					Timestamp:          time.Unix(0, 123456789012346).UTC(),
					StructuredMetadata: logproto.FromLabelsToLabelAdapters(labels.FromStrings("x", "a", "y", "b")),
				},
			},
		},
	}
	logStreams = []logproto.Stream{
		{
			Labels: `{test="test"}`,
			Entries: []logproto.Entry{
				{
					Line:      "super line",
					Timestamp: time.Unix(0, 123456789012345).UTC(),
				},
			},
		},
		{
			Labels: `{test="test", x="a", y="b"}`,
			Entries: []logproto.Entry{
				{
					Line:      "super line2",
					Timestamp: time.Unix(0, 123456789012346).UTC(),
				},
			},
		},
		{
			Labels: `{test="test", x="a", y="b", z="text"}`,
			Entries: []logproto.Entry{
				{
					Line:      "super line3 z=text",
					Timestamp: time.Unix(0, 123456789012346).UTC(),
				},
			},
		},
	}
	logStreamsWithCategories = []logproto.Stream{
		{
			Labels: `{test="test"}`,
			Entries: []logproto.Entry{
				{
					Line:      "super line",
					Timestamp: time.Unix(0, 123456789012345).UTC(),
				},
				{
					Line:               "super line2",
					Timestamp:          time.Unix(0, 123456789012346).UTC(),
					StructuredMetadata: logproto.FromLabelsToLabelAdapters(labels.FromStrings("x", "a", "y", "b")),
				},
				{
					Line:               "super line3 z=text",
					Timestamp:          time.Unix(0, 123456789012347).UTC(),
					StructuredMetadata: logproto.FromLabelsToLabelAdapters(labels.FromStrings("x", "a", "y", "b")),
					Parsed:             logproto.FromLabelsToLabelAdapters(labels.FromStrings("z", "text")),
				},
			},
		},
	}
	seriesString = `{
		"status": "success",
		"data": [
			{"filename": "/var/hostlog/apport.log", "job": "varlogs"},
			{"filename": "/var/hostlog/test.log", "job": "varlogs"}
		]
	}`
	seriesData = []logproto.SeriesIdentifier{
		{
			Labels: []logproto.SeriesIdentifier_LabelsEntry{
				{Key: "filename", Value: "/var/hostlog/apport.log"},
				{Key: "job", Value: "varlogs"},
			},
		},
		{
			Labels: []logproto.SeriesIdentifier_LabelsEntry{
				{Key: "filename", Value: "/var/hostlog/test.log"},
				{Key: "job", Value: "varlogs"},
			},
		},
	}
	labelsString = `{
		"status": "success",
		"data": [
			"foo",
			"bar"
		]
	}`
	labelsLegacyString = `{
		"values": [
			"foo",
			"bar"
		]
	}`
	indexStatsString = `{
		"streams": 1,
		"chunks": 2,
		"bytes": 3,
		"entries": 4
		}`
	seriesVolumeString = `{
    "limit": 100,
    "volumes": [
      {
        "name": "{foo=\"bar\"}",
        "volume": 38
      }
    ]
  }`
	labelsData  = []string{"foo", "bar"}
	statsResult = stats.Result{
		Summary: stats.Summary{
			BytesProcessedPerSecond: 20,
			QueueTime:               21,
			ExecTime:                22,
			LinesProcessedPerSecond: 23,
			TotalBytesProcessed:     24,
			TotalLinesProcessed:     25,
			TotalEntriesReturned:    10,
			TotalPostFilterLines:    0,
		},
		Querier: stats.Querier{
			Store: stats.Store{
				Chunk: stats.Chunk{
					CompressedBytes:   11,
					DecompressedBytes: 12,
					DecompressedLines: 13,
					HeadChunkBytes:    14,
					HeadChunkLines:    15,
					PostFilterLines:   0,
					TotalDuplicates:   19,
				},
				ChunksDownloadTime:           16,
				CongestionControlLatency:     0,
				TotalChunksRef:               17,
				TotalChunksDownloaded:        18,
				ChunkRefsFetchTime:           19,
				QueryReferencedStructured:    true,
				PipelineWrapperFilteredLines: 4,
			},
		},

		Ingester: stats.Ingester{
			Store: stats.Store{
				PipelineWrapperFilteredLines: 2,
				Chunk: stats.Chunk{
					CompressedBytes:   1,
					DecompressedBytes: 2,
					DecompressedLines: 3,
					HeadChunkBytes:    4,
					HeadChunkLines:    5,
					PostFilterLines:   0,
					TotalDuplicates:   8,
				},
			},
			TotalBatches:       6,
			TotalChunksMatched: 7,
			TotalLinesSent:     9,
			TotalReached:       10,
		},

		Caches: stats.Caches{
			Chunk:               stats.Cache{},
			Index:               stats.Cache{},
			StatsResult:         stats.Cache{},
			VolumeResult:        stats.Cache{},
			SeriesResult:        stats.Cache{},
			LabelResult:         stats.Cache{},
			Result:              stats.Cache{},
			InstantMetricResult: stats.Cache{},
		},
	}
)

func BenchmarkResponseMerge(b *testing.B) {
	const (
		resps         = 10
		streams       = 100
		logsPerStream = 1000
	)

	for _, tc := range []struct {
		desc  string
		limit uint32
		fn    func([]*LokiResponse, uint32, logproto.Direction) []logproto.Stream
	}{
		{
			"mergeStreams unlimited",
			uint32(streams * logsPerStream),
			mergeStreams,
		},
		{
			"mergeOrderedNonOverlappingStreams unlimited",
			uint32(streams * logsPerStream),
			mergeOrderedNonOverlappingStreams,
		},
		{
			"mergeStreams limited",
			uint32(streams*logsPerStream - 1),
			mergeStreams,
		},
		{
			"mergeOrderedNonOverlappingStreams limited",
			uint32(streams*logsPerStream - 1),
			mergeOrderedNonOverlappingStreams,
		},
	} {
		input := mkResps(resps, streams, logsPerStream, logproto.FORWARD)
		b.Run(tc.desc, func(b *testing.B) {
			for n := 0; n < b.N; n++ {
				tc.fn(input, tc.limit, logproto.FORWARD)
			}
		})
	}
}

func mkResps(nResps, nStreams, nLogs int, direction logproto.Direction) (resps []*LokiResponse) {
	for i := 0; i < nResps; i++ {
		r := &LokiResponse{}
		for j := 0; j < nStreams; j++ {
			stream := logproto.Stream{
				Labels: fmt.Sprintf(`{foo="%d"}`, j),
			}
			// split nLogs evenly across all responses
			for k := i * (nLogs / nResps); k < (i+1)*(nLogs/nResps); k++ {
				stream.Entries = append(stream.Entries, logproto.Entry{
					Timestamp: time.Unix(int64(k), 0),
					Line:      fmt.Sprintf("%d", k),
				})

				if direction == logproto.BACKWARD {
					for x, y := 0, len(stream.Entries)-1; x < len(stream.Entries)/2; x, y = x+1, y-1 {
						stream.Entries[x], stream.Entries[y] = stream.Entries[y], stream.Entries[x]
					}
				}
			}
			r.Data.Result = append(r.Data.Result, stream)
		}
		resps = append(resps, r)
	}
	return resps
}

type buffer struct {
	buff []byte
	io.ReadCloser
}

func (b *buffer) Bytes() []byte {
	return b.buff
}

func Benchmark_CodecDecodeLogs(b *testing.B) {
	ctx := context.Background()
	u := &url.URL{Path: "/loki/api/v1/query_range"}
	req := &http.Request{
		Method:     "GET",
		RequestURI: u.String(), // This is what the httpgrpc code looks at.
		URL:        u,
	}
	resp, err := DefaultCodec.EncodeResponse(ctx, req, &LokiResponse{
		Status:    loghttp.QueryStatusSuccess,
		Direction: logproto.BACKWARD,
		Version:   uint32(loghttp.VersionV1),
		Limit:     1000,
		Data: LokiData{
			ResultType: loghttp.ResultTypeStream,
			Result:     generateStream(),
		},
	})
	require.Nil(b, err)

	buf, err := io.ReadAll(resp.Body)
	require.Nil(b, err)
	reader := bytes.NewReader(buf)
	resp.Body = &buffer{
		ReadCloser: io.NopCloser(reader),
		buff:       buf,
	}
	b.ResetTimer()
	b.ReportAllocs()

	for n := 0; n < b.N; n++ {
		_, _ = reader.Seek(0, io.SeekStart)
		result, err := DefaultCodec.DecodeResponse(ctx, resp, &LokiRequest{
			Limit:     100,
			StartTs:   start,
			EndTs:     end,
			Direction: logproto.BACKWARD,
			Path:      u.String(),
		})
		require.Nil(b, err)
		require.NotNil(b, result)
	}
}

func Benchmark_CodecDecodeSamples(b *testing.B) {
	ctx := context.Background()
	u := &url.URL{Path: "/loki/api/v1/query_range"}
	req := &http.Request{
		Method:     "GET",
		RequestURI: u.String(), // This is what the httpgrpc code looks at.
		URL:        u,
	}
	resp, err := DefaultCodec.EncodeResponse(ctx, req, &LokiPromResponse{
		Response: &queryrangebase.PrometheusResponse{
			Status: loghttp.QueryStatusSuccess,
			Data: queryrangebase.PrometheusData{
				ResultType: loghttp.ResultTypeMatrix,
				Result:     generateMatrix(),
			},
		},
	})
	require.Nil(b, err)

	buf, err := io.ReadAll(resp.Body)
	require.Nil(b, err)
	reader := bytes.NewReader(buf)
	resp.Body = io.NopCloser(reader)
	b.ResetTimer()
	b.ReportAllocs()

	for n := 0; n < b.N; n++ {
		_, _ = reader.Seek(0, io.SeekStart)
		result, err := DefaultCodec.DecodeResponse(ctx, resp, &LokiRequest{
			Limit:     100,
			StartTs:   start,
			EndTs:     end,
			Direction: logproto.BACKWARD,
			Path:      u.String(),
		})
		require.NoError(b, err)
		require.NotNil(b, result)
	}
}

func Benchmark_CodecDecodeSeries(b *testing.B) {
	ctx := context.Background()
	benchmarks := []struct {
		accept string
	}{
		{accept: ProtobufType},
		{accept: JSONType},
	}

	for _, bm := range benchmarks {
		u := &url.URL{Path: "/loki/api/v1/series"}
		req := &http.Request{
			Method:     "GET",
			RequestURI: u.String(), // This is what the httpgrpc code looks at.
			URL:        u,
			Header: http.Header{
				"Accept": []string{bm.accept},
			},
		}
		resp, err := DefaultCodec.EncodeResponse(ctx, req, &LokiSeriesResponse{
			Status:     "200",
			Version:    1,
			Statistics: stats.Result{},
			Data:       generateSeries(),
		})
		require.Nil(b, err)

		buf, err := io.ReadAll(resp.Body)
		require.Nil(b, err)
		reader := bytes.NewReader(buf)
		resp.Body = io.NopCloser(reader)
		b.Run(bm.accept, func(b *testing.B) {
			b.ResetTimer()
			b.ReportAllocs()
			for n := 0; n < b.N; n++ {
				_, _ = reader.Seek(0, io.SeekStart)
				result, err := DefaultCodec.DecodeResponse(ctx, resp, &LokiSeriesRequest{
					StartTs: start,
					EndTs:   end,
					Path:    u.String(),
				})
				require.NoError(b, err)
				require.NotNil(b, result)
			}
		})
	}
}

func Benchmark_MergeResponses(b *testing.B) {
	var responses = make([]queryrangebase.Response, 100)
	for i := range responses {
		responses[i] = &LokiSeriesResponse{
			Status:     "200",
			Version:    1,
			Statistics: stats.Result{},
			Data:       generateSeries(),
		}
	}

	b.ResetTimer()
	b.ReportAllocs()

	for n := 0; n < b.N; n++ {
		result, err := DefaultCodec.MergeResponse(responses...)
		require.Nil(b, err)
		require.NotNil(b, result)
	}
}

func generateMatrix() (res []queryrangebase.SampleStream) {
	for i := 0; i < 100; i++ {
		s := queryrangebase.SampleStream{
			Labels:  []logproto.LabelAdapter{},
			Samples: []logproto.LegacySample{},
		}
		for j := 0; j < 1000; j++ {
			s.Samples = append(s.Samples, logproto.LegacySample{
				Value:       float64(j),
				TimestampMs: int64(j),
			})
		}
		res = append(res, s)
	}
	return res
}

func generateStream() (res []logproto.Stream) {
	for i := 0; i < 1000; i++ {
		s := logproto.Stream{
			Labels: fmt.Sprintf(`{foo="%d", buzz="bar", cluster="us-central2", namespace="loki-dev", container="query-frontend"}`, i),
		}
		for j := 0; j < 10; j++ {
			s.Entries = append(s.Entries, logproto.Entry{Timestamp: time.Now(), Line: fmt.Sprintf("%d\nyolo", j)})
		}
		res = append(res, s)
	}
	return res
}

func generateSeries() (res []logproto.SeriesIdentifier) {
	for i := 0; i < 1000; i++ {
		labels := make([]logproto.SeriesIdentifier_LabelsEntry, 100)
		for l := 0; l < 100; l++ {
			labels[l] = logproto.SeriesIdentifier_LabelsEntry{Key: fmt.Sprintf("%d-%d", i, l), Value: strconv.Itoa(l)}
		}
		res = append(res, logproto.SeriesIdentifier{Labels: labels})
	}
	return res
}