VictoriaMetrics/app/vlselect/logsql/logsql.go
Aliaksandr Valialkin a44787372f
app/vlselect/logsql: add an ability to delay returning matching logs from live tailing via offset query arg
By default the delay equals to 1 second.

While at it, document refresh_interval query arg at /select/logsql/tail endpoint.

Thanks to @Fusl for the idea and the initial implementation at https://github.com/VictoriaMetrics/VictoriaMetrics/pull/7428
2024-11-08 16:43:55 +01:00

1061 lines
26 KiB
Go

package logsql
import (
"context"
"fmt"
"math"
"net/http"
"slices"
"sort"
"strconv"
"strings"
"sync"
"time"
"github.com/VictoriaMetrics/metrics"
"github.com/VictoriaMetrics/VictoriaMetrics/app/vlstorage"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/httpserver"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/httputils"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/promutils"
)
// ProcessHitsRequest handles /select/logsql/hits request.
//
// See https://docs.victoriametrics.com/victorialogs/querying/#querying-hits-stats
func ProcessHitsRequest(ctx context.Context, w http.ResponseWriter, r *http.Request) {
q, tenantIDs, err := parseCommonArgs(r)
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
// Obtain step
stepStr := r.FormValue("step")
if stepStr == "" {
stepStr = "1d"
}
step, err := promutils.ParseDuration(stepStr)
if err != nil {
httpserver.Errorf(w, r, "cannot parse 'step' arg: %s", err)
return
}
if step <= 0 {
httpserver.Errorf(w, r, "'step' must be bigger than zero")
return
}
// Obtain offset
offsetStr := r.FormValue("offset")
if offsetStr == "" {
offsetStr = "0s"
}
offset, err := promutils.ParseDuration(offsetStr)
if err != nil {
httpserver.Errorf(w, r, "cannot parse 'offset' arg: %s", err)
return
}
// Obtain field entries
fields := r.Form["field"]
// Obtain limit on the number of top fields entries.
fieldsLimit, err := httputils.GetInt(r, "fields_limit")
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
if fieldsLimit < 0 {
fieldsLimit = 0
}
// Prepare the query for hits count.
q.DropAllPipes()
q.AddCountByTimePipe(int64(step), int64(offset), fields)
var mLock sync.Mutex
m := make(map[string]*hitsSeries)
writeBlock := func(_ uint, timestamps []int64, columns []logstorage.BlockColumn) {
if len(columns) == 0 || len(columns[0].Values) == 0 {
return
}
timestampValues := columns[0].Values
hitsValues := columns[len(columns)-1].Values
columns = columns[1 : len(columns)-1]
bb := blockResultPool.Get()
for i := range timestamps {
timestampStr := strings.Clone(timestampValues[i])
hitsStr := strings.Clone(hitsValues[i])
hits, err := strconv.ParseUint(hitsStr, 10, 64)
if err != nil {
logger.Panicf("BUG: cannot parse hitsStr=%q: %s", hitsStr, err)
}
bb.Reset()
WriteFieldsForHits(bb, columns, i)
mLock.Lock()
hs, ok := m[string(bb.B)]
if !ok {
k := string(bb.B)
hs = &hitsSeries{}
m[k] = hs
}
hs.timestamps = append(hs.timestamps, timestampStr)
hs.hits = append(hs.hits, hits)
hs.hitsTotal += hits
mLock.Unlock()
}
blockResultPool.Put(bb)
}
// Execute the query
if err := vlstorage.RunQuery(ctx, tenantIDs, q, writeBlock); err != nil {
httpserver.Errorf(w, r, "cannot execute query [%s]: %s", q, err)
return
}
m = getTopHitsSeries(m, fieldsLimit)
// Write response
w.Header().Set("Content-Type", "application/json")
WriteHitsSeries(w, m)
}
func getTopHitsSeries(m map[string]*hitsSeries, fieldsLimit int) map[string]*hitsSeries {
if fieldsLimit <= 0 || fieldsLimit >= len(m) {
return m
}
type fieldsHits struct {
fieldsStr string
hs *hitsSeries
}
a := make([]fieldsHits, 0, len(m))
for fieldsStr, hs := range m {
a = append(a, fieldsHits{
fieldsStr: fieldsStr,
hs: hs,
})
}
sort.Slice(a, func(i, j int) bool {
return a[i].hs.hitsTotal > a[j].hs.hitsTotal
})
hitsOther := make(map[string]uint64)
for _, x := range a[fieldsLimit:] {
for i, timestampStr := range x.hs.timestamps {
hitsOther[timestampStr] += x.hs.hits[i]
}
}
var hsOther hitsSeries
for timestampStr, hits := range hitsOther {
hsOther.timestamps = append(hsOther.timestamps, timestampStr)
hsOther.hits = append(hsOther.hits, hits)
hsOther.hitsTotal += hits
}
mNew := make(map[string]*hitsSeries, fieldsLimit+1)
for _, x := range a[:fieldsLimit] {
mNew[x.fieldsStr] = x.hs
}
mNew["{}"] = &hsOther
return mNew
}
type hitsSeries struct {
hitsTotal uint64
timestamps []string
hits []uint64
}
func (hs *hitsSeries) sort() {
sort.Sort(hs)
}
func (hs *hitsSeries) Len() int {
return len(hs.timestamps)
}
func (hs *hitsSeries) Swap(i, j int) {
hs.timestamps[i], hs.timestamps[j] = hs.timestamps[j], hs.timestamps[i]
hs.hits[i], hs.hits[j] = hs.hits[j], hs.hits[i]
}
func (hs *hitsSeries) Less(i, j int) bool {
return hs.timestamps[i] < hs.timestamps[j]
}
// ProcessFieldNamesRequest handles /select/logsql/field_names request.
//
// See https://docs.victoriametrics.com/victorialogs/querying/#querying-field-names
func ProcessFieldNamesRequest(ctx context.Context, w http.ResponseWriter, r *http.Request) {
q, tenantIDs, err := parseCommonArgs(r)
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
// Obtain field names for the given query
fieldNames, err := vlstorage.GetFieldNames(ctx, tenantIDs, q)
if err != nil {
httpserver.Errorf(w, r, "cannot obtain field names: %s", err)
return
}
// Write results
w.Header().Set("Content-Type", "application/json")
WriteValuesWithHitsJSON(w, fieldNames)
}
// ProcessFieldValuesRequest handles /select/logsql/field_values request.
//
// See https://docs.victoriametrics.com/victorialogs/querying/#querying-field-values
func ProcessFieldValuesRequest(ctx context.Context, w http.ResponseWriter, r *http.Request) {
q, tenantIDs, err := parseCommonArgs(r)
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
// Parse fieldName query arg
fieldName := r.FormValue("field")
if fieldName == "" {
httpserver.Errorf(w, r, "missing 'field' query arg")
return
}
// Parse limit query arg
limit, err := httputils.GetInt(r, "limit")
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
if limit < 0 {
limit = 0
}
// Obtain unique values for the given field
values, err := vlstorage.GetFieldValues(ctx, tenantIDs, q, fieldName, uint64(limit))
if err != nil {
httpserver.Errorf(w, r, "cannot obtain values for field %q: %s", fieldName, err)
return
}
// Write results
w.Header().Set("Content-Type", "application/json")
WriteValuesWithHitsJSON(w, values)
}
// ProcessStreamFieldNamesRequest processes /select/logsql/stream_field_names request.
//
// See https://docs.victoriametrics.com/victorialogs/querying/#querying-stream-field-names
func ProcessStreamFieldNamesRequest(ctx context.Context, w http.ResponseWriter, r *http.Request) {
q, tenantIDs, err := parseCommonArgs(r)
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
// Obtain stream field names for the given query
names, err := vlstorage.GetStreamFieldNames(ctx, tenantIDs, q)
if err != nil {
httpserver.Errorf(w, r, "cannot obtain stream field names: %s", err)
}
// Write results
w.Header().Set("Content-Type", "application/json")
WriteValuesWithHitsJSON(w, names)
}
// ProcessStreamFieldValuesRequest processes /select/logsql/stream_field_values request.
//
// See https://docs.victoriametrics.com/victorialogs/querying/#querying-stream-field-values
func ProcessStreamFieldValuesRequest(ctx context.Context, w http.ResponseWriter, r *http.Request) {
q, tenantIDs, err := parseCommonArgs(r)
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
// Parse fieldName query arg
fieldName := r.FormValue("field")
if fieldName == "" {
httpserver.Errorf(w, r, "missing 'field' query arg")
return
}
// Parse limit query arg
limit, err := httputils.GetInt(r, "limit")
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
if limit < 0 {
limit = 0
}
// Obtain stream field values for the given query and the given fieldName
values, err := vlstorage.GetStreamFieldValues(ctx, tenantIDs, q, fieldName, uint64(limit))
if err != nil {
httpserver.Errorf(w, r, "cannot obtain stream field values: %s", err)
}
// Write results
w.Header().Set("Content-Type", "application/json")
WriteValuesWithHitsJSON(w, values)
}
// ProcessStreamIDsRequest processes /select/logsql/stream_ids request.
//
// See https://docs.victoriametrics.com/victorialogs/querying/#querying-stream_ids
func ProcessStreamIDsRequest(ctx context.Context, w http.ResponseWriter, r *http.Request) {
q, tenantIDs, err := parseCommonArgs(r)
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
// Parse limit query arg
limit, err := httputils.GetInt(r, "limit")
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
if limit < 0 {
limit = 0
}
// Obtain streamIDs for the given query
streamIDs, err := vlstorage.GetStreamIDs(ctx, tenantIDs, q, uint64(limit))
if err != nil {
httpserver.Errorf(w, r, "cannot obtain stream_ids: %s", err)
}
// Write results
w.Header().Set("Content-Type", "application/json")
WriteValuesWithHitsJSON(w, streamIDs)
}
// ProcessStreamsRequest processes /select/logsql/streams request.
//
// See https://docs.victoriametrics.com/victorialogs/querying/#querying-streams
func ProcessStreamsRequest(ctx context.Context, w http.ResponseWriter, r *http.Request) {
q, tenantIDs, err := parseCommonArgs(r)
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
// Parse limit query arg
limit, err := httputils.GetInt(r, "limit")
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
if limit < 0 {
limit = 0
}
// Obtain streams for the given query
streams, err := vlstorage.GetStreams(ctx, tenantIDs, q, uint64(limit))
if err != nil {
httpserver.Errorf(w, r, "cannot obtain streams: %s", err)
}
// Write results
w.Header().Set("Content-Type", "application/json")
WriteValuesWithHitsJSON(w, streams)
}
// ProcessLiveTailRequest processes live tailing request to /select/logsq/tail
//
// See https://docs.victoriametrics.com/victorialogs/querying/#live-tailing
func ProcessLiveTailRequest(ctx context.Context, w http.ResponseWriter, r *http.Request) {
liveTailRequests.Inc()
defer liveTailRequests.Dec()
q, tenantIDs, err := parseCommonArgs(r)
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
if !q.CanLiveTail() {
httpserver.Errorf(w, r, "the query [%s] cannot be used in live tailing; "+
"see https://docs.victoriametrics.com/victorialogs/querying/#live-tailing for details", q)
return
}
refreshIntervalMsecs, err := httputils.GetDuration(r, "refresh_interval", 1000)
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
refreshInterval := time.Millisecond * time.Duration(refreshIntervalMsecs)
startOffsetMsecs, err := httputils.GetDuration(r, "start_offset", 5*1000)
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
startOffset := startOffsetMsecs * 1e6
offsetMsecs, err := httputils.GetDuration(r, "offset", 1000)
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
offset := offsetMsecs * 1e6
ctxWithCancel, cancel := context.WithCancel(ctx)
tp := newTailProcessor(cancel)
ticker := time.NewTicker(refreshInterval)
defer ticker.Stop()
end := time.Now().UnixNano() - offset
start := end - startOffset
doneCh := ctxWithCancel.Done()
flusher, ok := w.(http.Flusher)
if !ok {
logger.Panicf("BUG: it is expected that http.ResponseWriter (%T) supports http.Flusher interface", w)
}
qOrig := q
for {
q = qOrig.CloneWithTimeFilter(end, start, end)
if err := vlstorage.RunQuery(ctxWithCancel, tenantIDs, q, tp.writeBlock); err != nil {
httpserver.Errorf(w, r, "cannot execute tail query [%s]: %s", q, err)
return
}
resultRows, err := tp.getTailRows()
if err != nil {
httpserver.Errorf(w, r, "cannot get tail results for query [%q]: %s", q, err)
return
}
if len(resultRows) > 0 {
WriteJSONRows(w, resultRows)
flusher.Flush()
}
select {
case <-doneCh:
return
case <-ticker.C:
start = end - tailOffsetNsecs
end = time.Now().UnixNano() - offset
}
}
}
var liveTailRequests = metrics.NewCounter(`vl_live_tailing_requests`)
const tailOffsetNsecs = 5e9
type logRow struct {
timestamp int64
fields []logstorage.Field
}
func sortLogRows(rows []logRow) {
sort.SliceStable(rows, func(i, j int) bool {
return rows[i].timestamp < rows[j].timestamp
})
}
type tailProcessor struct {
cancel func()
mu sync.Mutex
perStreamRows map[string][]logRow
lastTimestamps map[string]int64
err error
}
func newTailProcessor(cancel func()) *tailProcessor {
return &tailProcessor{
cancel: cancel,
perStreamRows: make(map[string][]logRow),
lastTimestamps: make(map[string]int64),
}
}
func (tp *tailProcessor) writeBlock(_ uint, timestamps []int64, columns []logstorage.BlockColumn) {
if len(timestamps) == 0 {
return
}
tp.mu.Lock()
defer tp.mu.Unlock()
if tp.err != nil {
return
}
// Make sure columns contain _time field, since it is needed for proper tail work.
hasTime := false
for _, c := range columns {
if c.Name == "_time" {
hasTime = true
break
}
}
if !hasTime {
tp.err = fmt.Errorf("missing _time field")
tp.cancel()
return
}
// Copy block rows to tp.perStreamRows
for i, timestamp := range timestamps {
streamID := ""
fields := make([]logstorage.Field, len(columns))
for j, c := range columns {
name := strings.Clone(c.Name)
value := strings.Clone(c.Values[i])
fields[j] = logstorage.Field{
Name: name,
Value: value,
}
if name == "_stream_id" {
streamID = value
}
}
tp.perStreamRows[streamID] = append(tp.perStreamRows[streamID], logRow{
timestamp: timestamp,
fields: fields,
})
}
}
func (tp *tailProcessor) getTailRows() ([][]logstorage.Field, error) {
if tp.err != nil {
return nil, tp.err
}
var resultRows []logRow
for streamID, rows := range tp.perStreamRows {
sortLogRows(rows)
lastTimestamp, ok := tp.lastTimestamps[streamID]
if ok {
// Skip already written rows
for len(rows) > 0 && rows[0].timestamp <= lastTimestamp {
rows = rows[1:]
}
}
if len(rows) > 0 {
resultRows = append(resultRows, rows...)
tp.lastTimestamps[streamID] = rows[len(rows)-1].timestamp
}
}
clear(tp.perStreamRows)
sortLogRows(resultRows)
tailRows := make([][]logstorage.Field, len(resultRows))
for i, row := range resultRows {
tailRows[i] = row.fields
}
return tailRows, nil
}
// ProcessStatsQueryRangeRequest handles /select/logsql/stats_query_range request.
//
// See https://docs.victoriametrics.com/victorialogs/querying/#querying-log-range-stats
func ProcessStatsQueryRangeRequest(ctx context.Context, w http.ResponseWriter, r *http.Request) {
q, tenantIDs, err := parseCommonArgs(r)
if err != nil {
httpserver.SendPrometheusError(w, r, err)
return
}
// Obtain step
stepStr := r.FormValue("step")
if stepStr == "" {
stepStr = "1d"
}
step, err := promutils.ParseDuration(stepStr)
if err != nil {
err = fmt.Errorf("cannot parse 'step' arg: %s", err)
httpserver.SendPrometheusError(w, r, err)
return
}
if step <= 0 {
err := fmt.Errorf("'step' must be bigger than zero")
httpserver.SendPrometheusError(w, r, err)
return
}
// Obtain `by(...)` fields from the last `| stats` pipe in q.
// Add `_time:step` to the `by(...)` list.
byFields, err := q.GetStatsByFieldsAddGroupingByTime(int64(step))
if err != nil {
httpserver.SendPrometheusError(w, r, err)
return
}
m := make(map[string]*statsSeries)
var mLock sync.Mutex
writeBlock := func(_ uint, timestamps []int64, columns []logstorage.BlockColumn) {
clonedColumnNames := make([]string, len(columns))
for i, c := range columns {
clonedColumnNames[i] = strings.Clone(c.Name)
}
for i := range timestamps {
timestamp := q.GetTimestamp()
labels := make([]logstorage.Field, 0, len(byFields))
for j, c := range columns {
if c.Name == "_time" {
nsec, ok := logstorage.TryParseTimestampRFC3339Nano(c.Values[i])
if ok {
timestamp = nsec
continue
}
}
if slices.Contains(byFields, c.Name) {
labels = append(labels, logstorage.Field{
Name: clonedColumnNames[j],
Value: strings.Clone(c.Values[i]),
})
}
}
var dst []byte
for j, c := range columns {
if !slices.Contains(byFields, c.Name) {
name := clonedColumnNames[j]
dst = dst[:0]
dst = append(dst, name...)
dst = logstorage.MarshalFieldsToJSON(dst, labels)
key := string(dst)
p := statsPoint{
Timestamp: timestamp,
Value: strings.Clone(c.Values[i]),
}
mLock.Lock()
ss := m[key]
if ss == nil {
ss = &statsSeries{
key: key,
Name: name,
Labels: labels,
}
m[key] = ss
}
ss.Points = append(ss.Points, p)
mLock.Unlock()
}
}
}
}
if err := vlstorage.RunQuery(ctx, tenantIDs, q, writeBlock); err != nil {
err = fmt.Errorf("cannot execute query [%s]: %s", q, err)
httpserver.SendPrometheusError(w, r, err)
return
}
// Sort the collected stats by time
rows := make([]*statsSeries, 0, len(m))
for _, ss := range m {
points := ss.Points
sort.Slice(points, func(i, j int) bool {
return points[i].Timestamp < points[j].Timestamp
})
rows = append(rows, ss)
}
sort.Slice(rows, func(i, j int) bool {
return rows[i].key < rows[j].key
})
w.Header().Set("Content-Type", "application/json")
WriteStatsQueryRangeResponse(w, rows)
}
type statsSeries struct {
key string
Name string
Labels []logstorage.Field
Points []statsPoint
}
type statsPoint struct {
Timestamp int64
Value string
}
// ProcessStatsQueryRequest handles /select/logsql/stats_query request.
//
// See https://docs.victoriametrics.com/victorialogs/querying/#querying-log-stats
func ProcessStatsQueryRequest(ctx context.Context, w http.ResponseWriter, r *http.Request) {
q, tenantIDs, err := parseCommonArgs(r)
if err != nil {
httpserver.SendPrometheusError(w, r, err)
return
}
// Obtain `by(...)` fields from the last `| stats` pipe in q.
byFields, err := q.GetStatsByFields()
if err != nil {
httpserver.SendPrometheusError(w, r, err)
return
}
var rows []statsRow
var rowsLock sync.Mutex
timestamp := q.GetTimestamp()
writeBlock := func(_ uint, timestamps []int64, columns []logstorage.BlockColumn) {
clonedColumnNames := make([]string, len(columns))
for i, c := range columns {
clonedColumnNames[i] = strings.Clone(c.Name)
}
for i := range timestamps {
labels := make([]logstorage.Field, 0, len(byFields))
for j, c := range columns {
if slices.Contains(byFields, c.Name) {
labels = append(labels, logstorage.Field{
Name: clonedColumnNames[j],
Value: strings.Clone(c.Values[i]),
})
}
}
for j, c := range columns {
if !slices.Contains(byFields, c.Name) {
r := statsRow{
Name: clonedColumnNames[j],
Labels: labels,
Timestamp: timestamp,
Value: strings.Clone(c.Values[i]),
}
rowsLock.Lock()
rows = append(rows, r)
rowsLock.Unlock()
}
}
}
}
if err := vlstorage.RunQuery(ctx, tenantIDs, q, writeBlock); err != nil {
err = fmt.Errorf("cannot execute query [%s]: %s", q, err)
httpserver.SendPrometheusError(w, r, err)
return
}
w.Header().Set("Content-Type", "application/json")
WriteStatsQueryResponse(w, rows)
}
type statsRow struct {
Name string
Labels []logstorage.Field
Timestamp int64
Value string
}
// ProcessQueryRequest handles /select/logsql/query request.
//
// See https://docs.victoriametrics.com/victorialogs/querying/#querying-logs
func ProcessQueryRequest(ctx context.Context, w http.ResponseWriter, r *http.Request) {
q, tenantIDs, err := parseCommonArgs(r)
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
// Parse limit query arg
limit, err := httputils.GetInt(r, "limit")
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
bw := getBufferedWriter(w)
defer func() {
bw.FlushIgnoreErrors()
putBufferedWriter(bw)
}()
w.Header().Set("Content-Type", "application/stream+json")
if limit > 0 {
if q.CanReturnLastNResults() {
rows, err := getLastNQueryResults(ctx, tenantIDs, q, limit)
if err != nil {
httpserver.Errorf(w, r, "%s", err)
return
}
bb := blockResultPool.Get()
b := bb.B
for i := range rows {
b = logstorage.MarshalFieldsToJSON(b[:0], rows[i].fields)
b = append(b, '\n')
bw.WriteIgnoreErrors(b)
}
bb.B = b
blockResultPool.Put(bb)
return
}
q.AddPipeLimit(uint64(limit))
}
writeBlock := func(_ uint, timestamps []int64, columns []logstorage.BlockColumn) {
if len(columns) == 0 || len(columns[0].Values) == 0 {
return
}
bb := blockResultPool.Get()
for i := range timestamps {
WriteJSONRow(bb, columns, i)
}
bw.WriteIgnoreErrors(bb.B)
blockResultPool.Put(bb)
}
if err := vlstorage.RunQuery(ctx, tenantIDs, q, writeBlock); err != nil {
httpserver.Errorf(w, r, "cannot execute query [%s]: %s", q, err)
return
}
}
var blockResultPool bytesutil.ByteBufferPool
type row struct {
timestamp int64
fields []logstorage.Field
}
func getLastNQueryResults(ctx context.Context, tenantIDs []logstorage.TenantID, q *logstorage.Query, limit int) ([]row, error) {
limitUpper := 2 * limit
q.AddPipeLimit(uint64(limitUpper))
rows, err := getQueryResultsWithLimit(ctx, tenantIDs, q, limitUpper)
if err != nil {
return nil, err
}
if len(rows) < limitUpper {
// Fast path - the requested time range contains up to limitUpper rows.
rows = getLastNRows(rows, limit)
return rows, nil
}
// Slow path - adjust time range for selecting up to limitUpper rows
start, end := q.GetFilterTimeRange()
d := end/2 - start/2
start += d
qOrig := q
for {
timestamp := qOrig.GetTimestamp()
q = qOrig.CloneWithTimeFilter(timestamp, start, end)
rows, err := getQueryResultsWithLimit(ctx, tenantIDs, q, limitUpper)
if err != nil {
return nil, err
}
if d == 0 || start >= end {
// The [start ... end] time range equals one nanosecond.
// Just return up to limit rows.
if len(rows) > limit {
rows = rows[:limit]
}
return rows, nil
}
dLastBit := d & 1
d /= 2
if len(rows) >= limitUpper {
// The number of found rows on the [start ... end] time range exceeds limitUpper,
// so reduce the time range to [start+d ... end].
start += d
continue
}
if len(rows) >= limit {
// The number of found rows is in the range [limit ... limitUpper).
// This means that found rows contains the needed limit rows with the biggest timestamps.
rows = getLastNRows(rows, limit)
return rows, nil
}
// The number of found rows on [start ... end] time range is below the limit.
// This means the time range doesn't cover the needed logs, so it must be extended.
if len(rows) == 0 {
// The [start ... end] time range doesn't contain any rows, so change it to [start-d ... start).
end = start - 1
start -= d + dLastBit
continue
}
// The number of found rows on [start ... end] time range is bigger than 0 but smaller than limit.
// Increase the time range to [start-d ... end].
start -= d + dLastBit
}
}
func getLastNRows(rows []row, limit int) []row {
sort.Slice(rows, func(i, j int) bool {
return rows[i].timestamp < rows[j].timestamp
})
if len(rows) > limit {
rows = rows[len(rows)-limit:]
}
return rows
}
func getQueryResultsWithLimit(ctx context.Context, tenantIDs []logstorage.TenantID, q *logstorage.Query, limit int) ([]row, error) {
ctxWithCancel, cancel := context.WithCancel(ctx)
defer cancel()
var rows []row
var rowsLock sync.Mutex
writeBlock := func(_ uint, timestamps []int64, columns []logstorage.BlockColumn) {
clonedColumnNames := make([]string, len(columns))
for i, c := range columns {
clonedColumnNames[i] = strings.Clone(c.Name)
}
for i, timestamp := range timestamps {
fields := make([]logstorage.Field, len(columns))
for j := range columns {
f := &fields[j]
f.Name = clonedColumnNames[j]
f.Value = strings.Clone(columns[j].Values[i])
}
rowsLock.Lock()
rows = append(rows, row{
timestamp: timestamp,
fields: fields,
})
rowsLock.Unlock()
}
if len(rows) >= limit {
cancel()
}
}
if err := vlstorage.RunQuery(ctxWithCancel, tenantIDs, q, writeBlock); err != nil {
return nil, err
}
return rows, nil
}
func parseCommonArgs(r *http.Request) (*logstorage.Query, []logstorage.TenantID, error) {
// Extract tenantID
tenantID, err := logstorage.GetTenantIDFromRequest(r)
if err != nil {
return nil, nil, fmt.Errorf("cannot obtain tenanID: %w", err)
}
tenantIDs := []logstorage.TenantID{tenantID}
// Parse optional start and end args
start, okStart, err := getTimeNsec(r, "start")
if err != nil {
return nil, nil, err
}
end, okEnd, err := getTimeNsec(r, "end")
if err != nil {
return nil, nil, err
}
// Parse optional time arg
timestamp, okTime, err := getTimeNsec(r, "time")
if err != nil {
return nil, nil, err
}
if !okTime {
// If time arg is missing, then evaluate query either at the end timestamp (if it is set)
// or at the current timestamp (if end query arg isn't set)
if okEnd {
timestamp = end
} else {
timestamp = time.Now().UnixNano()
}
}
// decrease timestamp by one nanosecond in order to avoid capturing logs belonging
// to the first nanosecond at the next period of time (month, week, day, hour, etc.)
timestamp--
// Parse query
qStr := r.FormValue("query")
q, err := logstorage.ParseQueryAtTimestamp(qStr, timestamp)
if err != nil {
return nil, nil, fmt.Errorf("cannot parse query [%s]: %s", qStr, err)
}
if okStart || okEnd {
// Add _time:[start, end] filter if start or end args were set.
if !okStart {
start = math.MinInt64
}
if !okEnd {
end = math.MaxInt64
}
q.AddTimeFilter(start, end)
}
// Parse optional extra_filters
extraFilters, err := getExtraFilters(r, "extra_filters")
if err != nil {
return nil, nil, err
}
q.AddExtraFilters(extraFilters)
// Parse optional extra_stream_filters
extraStreamFilters, err := getExtraFilters(r, "extra_stream_filters")
if err != nil {
return nil, nil, err
}
q.AddExtraStreamFilters(extraStreamFilters)
return q, tenantIDs, nil
}
func getTimeNsec(r *http.Request, argName string) (int64, bool, error) {
s := r.FormValue(argName)
if s == "" {
return 0, false, nil
}
currentTimestamp := time.Now().UnixNano()
nsecs, err := promutils.ParseTimeAt(s, currentTimestamp)
if err != nil {
return 0, false, fmt.Errorf("cannot parse %s=%s: %w", argName, s, err)
}
return nsecs, true, nil
}
func getExtraFilters(r *http.Request, argName string) ([]logstorage.Field, error) {
s := r.FormValue(argName)
if s == "" {
return nil, nil
}
var p logstorage.JSONParser
if err := p.ParseLogMessage([]byte(s)); err != nil {
return nil, fmt.Errorf("cannot parse %s: %w", argName, err)
}
return p.Fields, nil
}