VictoriaMetrics/app/vmselect/prometheus/prometheus.go

797 lines
22 KiB
Go

package prometheus
import (
"flag"
"fmt"
"math"
"net/http"
"runtime"
"sort"
"strconv"
"strings"
"sync"
"time"
"github.com/VictoriaMetrics/VictoriaMetrics/app/vmselect/netstorage"
"github.com/VictoriaMetrics/VictoriaMetrics/app/vmselect/promql"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/storage"
"github.com/VictoriaMetrics/metrics"
"github.com/valyala/quicktemplate"
)
var (
latencyOffset = flag.Duration("search.latencyOffset", time.Second*30, "The time when data points become visible in query results after the colection. "+
"Too small value can result in incomplete last points for query results")
maxQueryDuration = flag.Duration("search.maxQueryDuration", time.Second*30, "The maximum time for search query execution")
maxQueryLen = flag.Int("search.maxQueryLen", 16*1024, "The maximum search query length in bytes")
maxLookback = flag.Duration("search.maxLookback", 0, "Synonim to `-search.lookback-delta` from Prometheus. "+
"The value is dynamically detected from interval between time series datapoints if not set. It can be overridden on per-query basis via `max_lookback` arg")
)
// Default step used if not set.
const defaultStep = 5 * 60 * 1000
// FederateHandler implements /federate . See https://prometheus.io/docs/prometheus/latest/federation/
func FederateHandler(w http.ResponseWriter, r *http.Request) error {
startTime := time.Now()
ct := currentTime()
if err := r.ParseForm(); err != nil {
return fmt.Errorf("cannot parse request form values: %s", err)
}
matches := r.Form["match[]"]
if len(matches) == 0 {
return fmt.Errorf("missing `match[]` arg")
}
lookbackDelta, err := getMaxLookback(r)
if err != nil {
return err
}
if lookbackDelta <= 0 {
lookbackDelta = defaultStep
}
start, err := getTime(r, "start", ct-lookbackDelta)
if err != nil {
return err
}
end, err := getTime(r, "end", ct)
if err != nil {
return err
}
deadline := getDeadline(r)
if start >= end {
start = end - defaultStep
}
tagFilterss, err := getTagFilterssFromMatches(matches)
if err != nil {
return err
}
sq := &storage.SearchQuery{
MinTimestamp: start,
MaxTimestamp: end,
TagFilterss: tagFilterss,
}
rss, err := netstorage.ProcessSearchQuery(sq, true, deadline)
if err != nil {
return fmt.Errorf("cannot fetch data for %q: %s", sq, err)
}
resultsCh := make(chan *quicktemplate.ByteBuffer)
doneCh := make(chan error)
go func() {
err := rss.RunParallel(func(rs *netstorage.Result, workerID uint) {
bb := quicktemplate.AcquireByteBuffer()
WriteFederate(bb, rs)
resultsCh <- bb
})
close(resultsCh)
doneCh <- err
}()
w.Header().Set("Content-Type", "text/plain")
for bb := range resultsCh {
w.Write(bb.B)
quicktemplate.ReleaseByteBuffer(bb)
}
err = <-doneCh
if err != nil {
return fmt.Errorf("error during data fetching: %s", err)
}
federateDuration.UpdateDuration(startTime)
return nil
}
var federateDuration = metrics.NewSummary(`vm_request_duration_seconds{path="/federate"}`)
// ExportHandler exports data in raw format from /api/v1/export.
func ExportHandler(w http.ResponseWriter, r *http.Request) error {
startTime := time.Now()
ct := currentTime()
if err := r.ParseForm(); err != nil {
return fmt.Errorf("cannot parse request form values: %s", err)
}
matches := r.Form["match[]"]
if len(matches) == 0 {
// Maintain backwards compatibility
match := r.FormValue("match")
if len(match) == 0 {
return fmt.Errorf("missing `match[]` arg")
}
matches = []string{match}
}
start, err := getTime(r, "start", 0)
if err != nil {
return err
}
end, err := getTime(r, "end", ct)
if err != nil {
return err
}
format := r.FormValue("format")
deadline := getDeadline(r)
if start >= end {
end = start + defaultStep
}
if err := exportHandler(w, matches, start, end, format, deadline); err != nil {
return err
}
exportDuration.UpdateDuration(startTime)
return nil
}
var exportDuration = metrics.NewSummary(`vm_request_duration_seconds{path="/api/v1/export"}`)
func exportHandler(w http.ResponseWriter, matches []string, start, end int64, format string, deadline netstorage.Deadline) error {
writeResponseFunc := WriteExportStdResponse
writeLineFunc := WriteExportJSONLine
contentType := "application/stream+json"
if format == "prometheus" {
contentType = "text/plain"
writeLineFunc = WriteExportPrometheusLine
} else if format == "promapi" {
writeResponseFunc = WriteExportPromAPIResponse
writeLineFunc = WriteExportPromAPILine
}
tagFilterss, err := getTagFilterssFromMatches(matches)
if err != nil {
return err
}
sq := &storage.SearchQuery{
MinTimestamp: start,
MaxTimestamp: end,
TagFilterss: tagFilterss,
}
rss, err := netstorage.ProcessSearchQuery(sq, true, deadline)
if err != nil {
return fmt.Errorf("cannot fetch data for %q: %s", sq, err)
}
resultsCh := make(chan *quicktemplate.ByteBuffer, runtime.GOMAXPROCS(-1))
doneCh := make(chan error)
go func() {
err := rss.RunParallel(func(rs *netstorage.Result, workerID uint) {
bb := quicktemplate.AcquireByteBuffer()
writeLineFunc(bb, rs)
resultsCh <- bb
})
close(resultsCh)
doneCh <- err
}()
w.Header().Set("Content-Type", contentType)
writeResponseFunc(w, resultsCh)
// Consume all the data from resultsCh in the event writeResponseFunc
// fails to consume all the data.
for bb := range resultsCh {
quicktemplate.ReleaseByteBuffer(bb)
}
err = <-doneCh
if err != nil {
return fmt.Errorf("error during data fetching: %s", err)
}
return nil
}
// DeleteHandler processes /api/v1/admin/tsdb/delete_series prometheus API request.
//
// See https://prometheus.io/docs/prometheus/latest/querying/api/#delete-series
func DeleteHandler(r *http.Request) error {
startTime := time.Now()
if err := r.ParseForm(); err != nil {
return fmt.Errorf("cannot parse request form values: %s", err)
}
if r.FormValue("start") != "" || r.FormValue("end") != "" {
return fmt.Errorf("start and end aren't supported. Remove these args from the query in order to delete all the matching metrics")
}
matches := r.Form["match[]"]
if len(matches) == 0 {
return fmt.Errorf("missing `match[]` arg")
}
tagFilterss, err := getTagFilterssFromMatches(matches)
if err != nil {
return err
}
sq := &storage.SearchQuery{
TagFilterss: tagFilterss,
}
deletedCount, err := netstorage.DeleteSeries(sq)
if err != nil {
return fmt.Errorf("cannot delete time series matching %q: %s", matches, err)
}
if deletedCount > 0 {
promql.ResetRollupResultCache()
}
deleteDuration.UpdateDuration(startTime)
return nil
}
var deleteDuration = metrics.NewSummary(`vm_request_duration_seconds{path="/api/v1/admin/tsdb/delete_series"}`)
// LabelValuesHandler processes /api/v1/label/<labelName>/values request.
//
// See https://prometheus.io/docs/prometheus/latest/querying/api/#querying-label-values
func LabelValuesHandler(labelName string, w http.ResponseWriter, r *http.Request) error {
startTime := time.Now()
deadline := getDeadline(r)
if err := r.ParseForm(); err != nil {
return fmt.Errorf("cannot parse form values: %s", err)
}
var labelValues []string
if len(r.Form["match[]"]) == 0 && len(r.Form["start"]) == 0 && len(r.Form["end"]) == 0 {
var err error
labelValues, err = netstorage.GetLabelValues(labelName, deadline)
if err != nil {
return fmt.Errorf(`cannot obtain label values for %q: %s`, labelName, err)
}
} else {
// Extended functionality that allows filtering by label filters and time range
// i.e. /api/v1/label/foo/values?match[]=foobar{baz="abc"}&start=...&end=...
// is equivalent to `label_values(foobar{baz="abc"}, foo)` call on the selected
// time range in Grafana templating.
matches := r.Form["match[]"]
if len(matches) == 0 {
matches = []string{fmt.Sprintf("{%s!=''}", labelName)}
}
ct := currentTime()
end, err := getTime(r, "end", ct)
if err != nil {
return err
}
start, err := getTime(r, "start", end-defaultStep)
if err != nil {
return err
}
labelValues, err = labelValuesWithMatches(labelName, matches, start, end, deadline)
if err != nil {
return fmt.Errorf("cannot obtain label values for %q, match[]=%q, start=%d, end=%d: %s", labelName, matches, start, end, err)
}
}
w.Header().Set("Content-Type", "application/json")
WriteLabelValuesResponse(w, labelValues)
labelValuesDuration.UpdateDuration(startTime)
return nil
}
func labelValuesWithMatches(labelName string, matches []string, start, end int64, deadline netstorage.Deadline) ([]string, error) {
if len(matches) == 0 {
logger.Panicf("BUG: matches must be non-empty")
}
tagFilterss, err := getTagFilterssFromMatches(matches)
if err != nil {
return nil, err
}
if start >= end {
end = start + defaultStep
}
sq := &storage.SearchQuery{
MinTimestamp: start,
MaxTimestamp: end,
TagFilterss: tagFilterss,
}
rss, err := netstorage.ProcessSearchQuery(sq, false, deadline)
if err != nil {
return nil, fmt.Errorf("cannot fetch data for %q: %s", sq, err)
}
m := make(map[string]struct{})
var mLock sync.Mutex
err = rss.RunParallel(func(rs *netstorage.Result, workerID uint) {
labelValue := rs.MetricName.GetTagValue(labelName)
if len(labelValue) == 0 {
return
}
mLock.Lock()
m[string(labelValue)] = struct{}{}
mLock.Unlock()
})
if err != nil {
return nil, fmt.Errorf("error when data fetching: %s", err)
}
labelValues := make([]string, 0, len(m))
for labelValue := range m {
labelValues = append(labelValues, labelValue)
}
sort.Strings(labelValues)
return labelValues, nil
}
var labelValuesDuration = metrics.NewSummary(`vm_request_duration_seconds{path="/api/v1/label/{}/values"}`)
// LabelsCountHandler processes /api/v1/labels/count request.
func LabelsCountHandler(w http.ResponseWriter, r *http.Request) error {
startTime := time.Now()
deadline := getDeadline(r)
labelEntries, err := netstorage.GetLabelEntries(deadline)
if err != nil {
return fmt.Errorf(`cannot obtain label entries: %s`, err)
}
w.Header().Set("Content-Type", "application/json")
WriteLabelsCountResponse(w, labelEntries)
labelsCountDuration.UpdateDuration(startTime)
return nil
}
var labelsCountDuration = metrics.NewSummary(`vm_request_duration_seconds{path="/api/v1/labels/count"}`)
// LabelsHandler processes /api/v1/labels request.
//
// See https://prometheus.io/docs/prometheus/latest/querying/api/#getting-label-names
func LabelsHandler(w http.ResponseWriter, r *http.Request) error {
startTime := time.Now()
deadline := getDeadline(r)
labels, err := netstorage.GetLabels(deadline)
if err != nil {
return fmt.Errorf("cannot obtain labels: %s", err)
}
w.Header().Set("Content-Type", "application/json")
WriteLabelsResponse(w, labels)
labelsDuration.UpdateDuration(startTime)
return nil
}
var labelsDuration = metrics.NewSummary(`vm_request_duration_seconds{path="/api/v1/labels"}`)
// SeriesCountHandler processes /api/v1/series/count request.
func SeriesCountHandler(w http.ResponseWriter, r *http.Request) error {
startTime := time.Now()
deadline := getDeadline(r)
n, err := netstorage.GetSeriesCount(deadline)
if err != nil {
return fmt.Errorf("cannot obtain series count: %s", err)
}
w.Header().Set("Content-Type", "application/json")
WriteSeriesCountResponse(w, n)
seriesCountDuration.UpdateDuration(startTime)
return nil
}
var seriesCountDuration = metrics.NewSummary(`vm_request_duration_seconds{path="/api/v1/series/count"}`)
// SeriesHandler processes /api/v1/series request.
//
// See https://prometheus.io/docs/prometheus/latest/querying/api/#finding-series-by-label-matchers
func SeriesHandler(w http.ResponseWriter, r *http.Request) error {
startTime := time.Now()
ct := currentTime()
if err := r.ParseForm(); err != nil {
return fmt.Errorf("cannot parse form values: %s", err)
}
matches := r.Form["match[]"]
if len(matches) == 0 {
return fmt.Errorf("missing `match[]` arg")
}
end, err := getTime(r, "end", ct)
if err != nil {
return err
}
// Do not set start to minTimeMsecs by default as Prometheus does,
// since this leads to fetching and scanning all the data from the storage,
// which can take a lot of time for big storages.
// It is better setting start as end-defaultStep by default.
// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/91
start, err := getTime(r, "start", end-defaultStep)
if err != nil {
return err
}
deadline := getDeadline(r)
tagFilterss, err := getTagFilterssFromMatches(matches)
if err != nil {
return err
}
if start >= end {
end = start + defaultStep
}
sq := &storage.SearchQuery{
MinTimestamp: start,
MaxTimestamp: end,
TagFilterss: tagFilterss,
}
rss, err := netstorage.ProcessSearchQuery(sq, false, deadline)
if err != nil {
return fmt.Errorf("cannot fetch data for %q: %s", sq, err)
}
resultsCh := make(chan *quicktemplate.ByteBuffer)
doneCh := make(chan error)
go func() {
err := rss.RunParallel(func(rs *netstorage.Result, workerID uint) {
bb := quicktemplate.AcquireByteBuffer()
writemetricNameObject(bb, &rs.MetricName)
resultsCh <- bb
})
close(resultsCh)
doneCh <- err
}()
w.Header().Set("Content-Type", "application/json")
WriteSeriesResponse(w, resultsCh)
// Consume all the data from resultsCh in the event WriteSeriesResponse
// fails to consume all the data.
for bb := range resultsCh {
quicktemplate.ReleaseByteBuffer(bb)
}
err = <-doneCh
if err != nil {
return fmt.Errorf("error during data fetching: %s", err)
}
seriesDuration.UpdateDuration(startTime)
return nil
}
var seriesDuration = metrics.NewSummary(`vm_request_duration_seconds{path="/api/v1/series"}`)
// QueryHandler processes /api/v1/query request.
//
// See https://prometheus.io/docs/prometheus/latest/querying/api/#instant-queries
func QueryHandler(w http.ResponseWriter, r *http.Request) error {
startTime := time.Now()
ct := currentTime()
query := r.FormValue("query")
if len(query) == 0 {
return fmt.Errorf("missing `query` arg")
}
start, err := getTime(r, "time", ct)
if err != nil {
return err
}
queryOffset := getLatencyOffsetMilliseconds()
step, err := getDuration(r, "step", queryOffset)
if err != nil {
return err
}
deadline := getDeadline(r)
lookbackDelta, err := getMaxLookback(r)
if err != nil {
return err
}
if len(query) > *maxQueryLen {
return fmt.Errorf(`too long query; got %d bytes; mustn't exceed %d bytes`, len(query), *maxQueryLen)
}
if !getBool(r, "nocache") && ct-start < queryOffset {
// Adjust start time only if `nocache` arg isn't set.
// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/241
start = ct - queryOffset
}
if childQuery, windowStr, offsetStr := promql.IsMetricSelectorWithRollup(query); childQuery != "" {
var window int64
if len(windowStr) > 0 {
var err error
window, err = promql.DurationValue(windowStr, step)
if err != nil {
return err
}
}
var offset int64
if len(offsetStr) > 0 {
var err error
offset, err = promql.DurationValue(offsetStr, step)
if err != nil {
return err
}
}
start -= offset
end := start
start = end - window
if err := exportHandler(w, []string{childQuery}, start, end, "promapi", deadline); err != nil {
return err
}
queryDuration.UpdateDuration(startTime)
return nil
}
ec := promql.EvalConfig{
Start: start,
End: start,
Step: step,
Deadline: deadline,
LookbackDelta: lookbackDelta,
}
result, err := promql.Exec(&ec, query, true)
if err != nil {
return fmt.Errorf("cannot execute %q: %s", query, err)
}
w.Header().Set("Content-Type", "application/json")
WriteQueryResponse(w, result)
queryDuration.UpdateDuration(startTime)
return nil
}
var queryDuration = metrics.NewSummary(`vm_request_duration_seconds{path="/api/v1/query"}`)
// QueryRangeHandler processes /api/v1/query_range request.
//
// See https://prometheus.io/docs/prometheus/latest/querying/api/#range-queries
func QueryRangeHandler(w http.ResponseWriter, r *http.Request) error {
startTime := time.Now()
ct := currentTime()
query := r.FormValue("query")
if len(query) == 0 {
return fmt.Errorf("missing `query` arg")
}
start, err := getTime(r, "start", ct-defaultStep)
if err != nil {
return err
}
end, err := getTime(r, "end", ct)
if err != nil {
return err
}
step, err := getDuration(r, "step", defaultStep)
if err != nil {
return err
}
deadline := getDeadline(r)
mayCache := !getBool(r, "nocache")
lookbackDelta, err := getMaxLookback(r)
if err != nil {
return err
}
// Validate input args.
if len(query) > *maxQueryLen {
return fmt.Errorf(`too long query; got %d bytes; mustn't exceed %d bytes`, len(query), *maxQueryLen)
}
if start > end {
end = start + defaultStep
}
if err := promql.ValidateMaxPointsPerTimeseries(start, end, step); err != nil {
return err
}
if mayCache {
start, end = promql.AdjustStartEnd(start, end, step)
}
ec := promql.EvalConfig{
Start: start,
End: end,
Step: step,
Deadline: deadline,
MayCache: mayCache,
LookbackDelta: lookbackDelta,
}
result, err := promql.Exec(&ec, query, false)
if err != nil {
return fmt.Errorf("cannot execute %q: %s", query, err)
}
queryOffset := getLatencyOffsetMilliseconds()
if ct-end < queryOffset {
result = adjustLastPoints(result)
}
// Remove NaN values as Prometheus does.
// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/153
removeNaNValuesInplace(result)
w.Header().Set("Content-Type", "application/json")
WriteQueryRangeResponse(w, result)
queryRangeDuration.UpdateDuration(startTime)
return nil
}
func removeNaNValuesInplace(tss []netstorage.Result) {
for i := range tss {
ts := &tss[i]
hasNaNs := false
for _, v := range ts.Values {
if math.IsNaN(v) {
hasNaNs = true
break
}
}
if !hasNaNs {
// Fast path: nothing to remove.
continue
}
// Slow path: remove NaNs.
srcTimestamps := ts.Timestamps
dstValues := ts.Values[:0]
dstTimestamps := ts.Timestamps[:0]
for j, v := range ts.Values {
if math.IsNaN(v) {
continue
}
dstValues = append(dstValues, v)
dstTimestamps = append(dstTimestamps, srcTimestamps[j])
}
ts.Values = dstValues
ts.Timestamps = dstTimestamps
}
}
var queryRangeDuration = metrics.NewSummary(`vm_request_duration_seconds{path="/api/v1/query_range"}`)
// adjustLastPoints substitutes the last point values with the previous
// point values, since the last points may contain garbage.
func adjustLastPoints(tss []netstorage.Result) []netstorage.Result {
if len(tss) == 0 {
return nil
}
// Search for the last non-NaN value across all the timeseries.
lastNonNaNIdx := -1
for i := range tss {
values := tss[i].Values
j := len(values) - 1
for j >= 0 && math.IsNaN(values[j]) {
j--
}
if j > lastNonNaNIdx {
lastNonNaNIdx = j
}
}
if lastNonNaNIdx == -1 {
// All timeseries contain only NaNs.
return nil
}
// Substitute the last two values starting from lastNonNaNIdx
// with the previous values for each timeseries.
for i := range tss {
values := tss[i].Values
for j := 0; j < 2; j++ {
idx := lastNonNaNIdx + j
if idx <= 0 || idx >= len(values) || math.IsNaN(values[idx-1]) {
continue
}
values[idx] = values[idx-1]
}
}
return tss
}
func getTime(r *http.Request, argKey string, defaultValue int64) (int64, error) {
argValue := r.FormValue(argKey)
if len(argValue) == 0 {
return defaultValue, nil
}
secs, err := strconv.ParseFloat(argValue, 64)
if err != nil {
// Try parsing string format
t, err := time.Parse(time.RFC3339, argValue)
if err != nil {
// Handle Prometheus'-provided minTime and maxTime.
// See https://github.com/prometheus/client_golang/issues/614
switch argValue {
case prometheusMinTimeFormatted:
return minTimeMsecs, nil
case prometheusMaxTimeFormatted:
return maxTimeMsecs, nil
}
return 0, fmt.Errorf("cannot parse %q=%q: %s", argKey, argValue, err)
}
secs = float64(t.UnixNano()) / 1e9
}
msecs := int64(secs * 1e3)
if msecs < minTimeMsecs {
msecs = 0
}
if msecs > maxTimeMsecs {
msecs = maxTimeMsecs
}
return msecs, nil
}
var (
// These constants were obtained from https://github.com/prometheus/prometheus/blob/91d7175eaac18b00e370965f3a8186cc40bf9f55/web/api/v1/api.go#L442
// See https://github.com/prometheus/client_golang/issues/614 for details.
prometheusMinTimeFormatted = time.Unix(math.MinInt64/1000+62135596801, 0).UTC().Format(time.RFC3339Nano)
prometheusMaxTimeFormatted = time.Unix(math.MaxInt64/1000-62135596801, 999999999).UTC().Format(time.RFC3339Nano)
)
const (
// These values prevent from overflow when storing msec-precision time in int64.
minTimeMsecs = 0 // use 0 instead of `int64(-1<<63) / 1e6` because the storage engine doesn't actually support negative time
maxTimeMsecs = int64(1<<63-1) / 1e6
)
func getDuration(r *http.Request, argKey string, defaultValue int64) (int64, error) {
argValue := r.FormValue(argKey)
if len(argValue) == 0 {
return defaultValue, nil
}
secs, err := strconv.ParseFloat(argValue, 64)
if err != nil {
// Try parsing string format
d, err := time.ParseDuration(argValue)
if err != nil {
return 0, fmt.Errorf("cannot parse %q=%q: %s", argKey, argValue, err)
}
secs = d.Seconds()
}
msecs := int64(secs * 1e3)
if msecs <= 0 || msecs > maxDurationMsecs {
return 0, fmt.Errorf("%q=%dms is out of allowed range [%d ... %d]", argKey, msecs, 0, int64(maxDurationMsecs))
}
return msecs, nil
}
const maxDurationMsecs = 100 * 365 * 24 * 3600 * 1000
func getMaxLookback(r *http.Request) (int64, error) {
d := int64(*maxLookback / time.Millisecond)
return getDuration(r, "max_lookback", d)
}
func getDeadline(r *http.Request) netstorage.Deadline {
d, err := getDuration(r, "timeout", 0)
if err != nil {
d = 0
}
dMax := int64(maxQueryDuration.Seconds() * 1e3)
if d <= 0 || d > dMax {
d = dMax
}
timeout := time.Duration(d) * time.Millisecond
return netstorage.NewDeadline(timeout)
}
func getBool(r *http.Request, argKey string) bool {
argValue := r.FormValue(argKey)
switch strings.ToLower(argValue) {
case "", "0", "f", "false", "no":
return false
default:
return true
}
}
func currentTime() int64 {
return int64(time.Now().UTC().Unix()) * 1e3
}
func getTagFilterssFromMatches(matches []string) ([][]storage.TagFilter, error) {
tagFilterss := make([][]storage.TagFilter, 0, len(matches))
for _, match := range matches {
tagFilters, err := promql.ParseMetricSelector(match)
if err != nil {
return nil, fmt.Errorf("cannot parse %q: %s", match, err)
}
tagFilterss = append(tagFilterss, tagFilters)
}
return tagFilterss, nil
}
func getLatencyOffsetMilliseconds() int64 {
d := int64(*latencyOffset / time.Millisecond)
if d <= 1000 {
d = 1000
}
return d
}