VictoriaMetrics/lib/promrelabel/config.go

378 lines
11 KiB
Go

package promrelabel
import (
"fmt"
"regexp"
"strconv"
"strings"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/envtemplate"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/fs"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/regexutil"
"gopkg.in/yaml.v2"
)
// RelabelConfig represents relabel config.
//
// See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#relabel_config
type RelabelConfig struct {
SourceLabels []string `yaml:"source_labels,flow,omitempty"`
Separator *string `yaml:"separator,omitempty"`
TargetLabel string `yaml:"target_label,omitempty"`
Regex *MultiLineRegex `yaml:"regex,omitempty"`
Modulus uint64 `yaml:"modulus,omitempty"`
Replacement *string `yaml:"replacement,omitempty"`
Action string `yaml:"action,omitempty"`
If *IfExpression `yaml:"if,omitempty"`
// Match is used together with Labels for `action: graphite`. For example:
// - action: graphite
// match: 'foo.*.*.bar'
// labels:
// job: '$1'
// instance: '${2}:8080'
Match string `yaml:"match,omitempty"`
// Labels is used together with Match for `action: graphite`. For example:
// - action: graphite
// match: 'foo.*.*.bar'
// labels:
// job: '$1'
// instance: '${2}:8080'
Labels map[string]string `yaml:"labels,omitempty"`
}
// MultiLineRegex contains a regex, which can be split into multiple lines.
//
// These lines are joined with "|" then.
// For example:
//
// regex:
// - foo
// - bar
//
// is equivalent to:
//
// regex: "foo|bar"
type MultiLineRegex struct {
S string
}
// UnmarshalYAML unmarshals mlr from YAML passed to f.
func (mlr *MultiLineRegex) UnmarshalYAML(f func(interface{}) error) error {
var v interface{}
if err := f(&v); err != nil {
return fmt.Errorf("cannot parse multiline regex: %w", err)
}
s, err := stringValue(v)
if err != nil {
return err
}
mlr.S = s
return nil
}
func stringValue(v interface{}) (string, error) {
if v == nil {
return "null", nil
}
switch x := v.(type) {
case []interface{}:
a := make([]string, len(x))
for i, xx := range x {
s, err := stringValue(xx)
if err != nil {
return "", err
}
a[i] = s
}
return strings.Join(a, "|"), nil
case string:
return x, nil
case float64:
return strconv.FormatFloat(x, 'f', -1, 64), nil
case int:
return strconv.Itoa(x), nil
case bool:
if x {
return "true", nil
}
return "false", nil
default:
return "", fmt.Errorf("unexpected type for `regex`: %T; want string or []string", v)
}
}
// MarshalYAML marshals mlr to YAML.
func (mlr *MultiLineRegex) MarshalYAML() (interface{}, error) {
if strings.ContainsAny(mlr.S, "([") {
// The mlr.S contains groups. Fall back to returning the regexp as is without splitting it into parts.
// This fixes https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2928 .
return mlr.S, nil
}
a := strings.Split(mlr.S, "|")
if len(a) == 1 {
return a[0], nil
}
return a, nil
}
// ParsedConfigs represents parsed relabel configs.
type ParsedConfigs struct {
prcs []*parsedRelabelConfig
relabelDebug bool
}
// Len returns the number of relabel configs in pcs.
func (pcs *ParsedConfigs) Len() int {
if pcs == nil {
return 0
}
return len(pcs.prcs)
}
// String returns human-readabale representation for pcs.
func (pcs *ParsedConfigs) String() string {
if pcs == nil {
return ""
}
var a []string
for _, prc := range pcs.prcs {
s := "[" + prc.String() + "]"
a = append(a, s)
}
return fmt.Sprintf("%s, relabelDebug=%v", strings.Join(a, ","), pcs.relabelDebug)
}
// LoadRelabelConfigs loads relabel configs from the given path.
func LoadRelabelConfigs(path string, relabelDebug bool) (*ParsedConfigs, error) {
data, err := fs.ReadFileOrHTTP(path)
if err != nil {
return nil, fmt.Errorf("cannot read `relabel_configs` from %q: %w", path, err)
}
data = envtemplate.Replace(data)
pcs, err := ParseRelabelConfigsData(data, relabelDebug)
if err != nil {
return nil, fmt.Errorf("cannot unmarshal `relabel_configs` from %q: %w", path, err)
}
return pcs, nil
}
// ParseRelabelConfigsData parses relabel configs from the given data.
func ParseRelabelConfigsData(data []byte, relabelDebug bool) (*ParsedConfigs, error) {
var rcs []RelabelConfig
if err := yaml.UnmarshalStrict(data, &rcs); err != nil {
return nil, err
}
return ParseRelabelConfigs(rcs, relabelDebug)
}
// ParseRelabelConfigs parses rcs to dst.
func ParseRelabelConfigs(rcs []RelabelConfig, relabelDebug bool) (*ParsedConfigs, error) {
if len(rcs) == 0 {
return nil, nil
}
prcs := make([]*parsedRelabelConfig, len(rcs))
for i := range rcs {
prc, err := parseRelabelConfig(&rcs[i])
if err != nil {
return nil, fmt.Errorf("error when parsing `relabel_config` #%d: %w", i+1, err)
}
prcs[i] = prc
}
return &ParsedConfigs{
prcs: prcs,
relabelDebug: relabelDebug,
}, nil
}
var (
defaultOriginalRegexForRelabelConfig = regexp.MustCompile(".*")
defaultRegexForRelabelConfig = regexp.MustCompile("^(.*)$")
defaultPromRegex = func() *regexutil.PromRegex {
pr, err := regexutil.NewPromRegex(".*")
if err != nil {
panic(fmt.Errorf("BUG: unexpected error: %s", err))
}
return pr
}()
)
func parseRelabelConfig(rc *RelabelConfig) (*parsedRelabelConfig, error) {
sourceLabels := rc.SourceLabels
separator := ";"
if rc.Separator != nil {
separator = *rc.Separator
}
action := strings.ToLower(rc.Action)
if action == "" {
action = "replace"
}
targetLabel := rc.TargetLabel
regexAnchored := defaultRegexForRelabelConfig
regexOriginalCompiled := defaultOriginalRegexForRelabelConfig
promRegex := defaultPromRegex
if rc.Regex != nil && !isDefaultRegex(rc.Regex.S) {
regex := rc.Regex.S
regexOrig := regex
if rc.Action != "replace_all" && rc.Action != "labelmap_all" {
regex = regexutil.RemoveStartEndAnchors(regex)
regexOrig = regex
regex = "^(?:" + regex + ")$"
}
re, err := regexp.Compile(regex)
if err != nil {
return nil, fmt.Errorf("cannot parse `regex` %q: %w", regex, err)
}
regexAnchored = re
reOriginal, err := regexp.Compile(regexOrig)
if err != nil {
return nil, fmt.Errorf("cannot parse `regex` %q: %w", regexOrig, err)
}
regexOriginalCompiled = reOriginal
promRegex, err = regexutil.NewPromRegex(regexOrig)
if err != nil {
logger.Panicf("BUG: cannot parse already parsed regex %q: %s", regexOrig, err)
}
}
modulus := rc.Modulus
replacement := "$1"
if rc.Replacement != nil {
replacement = *rc.Replacement
}
var graphiteMatchTemplate *graphiteMatchTemplate
if rc.Match != "" {
graphiteMatchTemplate = newGraphiteMatchTemplate(rc.Match)
}
var graphiteLabelRules []graphiteLabelRule
if rc.Labels != nil {
graphiteLabelRules = newGraphiteLabelRules(rc.Labels)
}
switch action {
case "graphite":
if graphiteMatchTemplate == nil {
return nil, fmt.Errorf("missing `match` for `action=graphite`; see https://docs.victoriametrics.com/vmagent.html#graphite-relabeling")
}
if len(graphiteLabelRules) == 0 {
return nil, fmt.Errorf("missing `labels` for `action=graphite`; see https://docs.victoriametrics.com/vmagent.html#graphite-relabeling")
}
if len(rc.SourceLabels) > 0 {
return nil, fmt.Errorf("`source_labels` cannot be used with `action=graphite`; see https://docs.victoriametrics.com/vmagent.html#graphite-relabeling")
}
if rc.TargetLabel != "" {
return nil, fmt.Errorf("`target_label` cannot be used with `action=graphite`; see https://docs.victoriametrics.com/vmagent.html#graphite-relabeling")
}
if rc.Replacement != nil {
return nil, fmt.Errorf("`replacement` cannot be used with `action=graphite`; see https://docs.victoriametrics.com/vmagent.html#graphite-relabeling")
}
if rc.Regex != nil {
return nil, fmt.Errorf("`regex` cannot be used with `action=graphite`; see https://docs.victoriametrics.com/vmagent.html#graphite-relabeling")
}
case "replace":
if targetLabel == "" {
return nil, fmt.Errorf("missing `target_label` for `action=replace`")
}
case "replace_all":
if len(sourceLabels) == 0 {
return nil, fmt.Errorf("missing `source_labels` for `action=replace_all`")
}
if targetLabel == "" {
return nil, fmt.Errorf("missing `target_label` for `action=replace_all`")
}
case "keep_if_equal":
if len(sourceLabels) < 2 {
return nil, fmt.Errorf("`source_labels` must contain at least two entries for `action=keep_if_equal`; got %q", sourceLabels)
}
case "drop_if_equal":
if len(sourceLabels) < 2 {
return nil, fmt.Errorf("`source_labels` must contain at least two entries for `action=drop_if_equal`; got %q", sourceLabels)
}
case "keep":
if len(sourceLabels) == 0 && rc.If == nil {
return nil, fmt.Errorf("missing `source_labels` for `action=keep`")
}
case "drop":
if len(sourceLabels) == 0 && rc.If == nil {
return nil, fmt.Errorf("missing `source_labels` for `action=drop`")
}
case "hashmod":
if len(sourceLabels) == 0 {
return nil, fmt.Errorf("missing `source_labels` for `action=hashmod`")
}
if targetLabel == "" {
return nil, fmt.Errorf("missing `target_label` for `action=hashmod`")
}
if modulus < 1 {
return nil, fmt.Errorf("unexpected `modulus` for `action=hashmod`: %d; must be greater than 0", modulus)
}
case "keep_metrics":
if (rc.Regex == nil || rc.Regex.S == "") && rc.If == nil {
return nil, fmt.Errorf("`regex` must be non-empty for `action=keep_metrics`")
}
if len(sourceLabels) > 0 {
return nil, fmt.Errorf("`source_labels` must be empty for `action=keep_metrics`; got %q", sourceLabels)
}
sourceLabels = []string{"__name__"}
action = "keep"
case "drop_metrics":
if (rc.Regex == nil || rc.Regex.S == "") && rc.If == nil {
return nil, fmt.Errorf("`regex` must be non-empty for `action=drop_metrics`")
}
if len(sourceLabels) > 0 {
return nil, fmt.Errorf("`source_labels` must be empty for `action=drop_metrics`; got %q", sourceLabels)
}
sourceLabels = []string{"__name__"}
action = "drop"
case "uppercase", "lowercase":
if len(sourceLabels) == 0 {
return nil, fmt.Errorf("missing `source_labels` for `action=%s`", action)
}
if targetLabel == "" {
return nil, fmt.Errorf("missing `target_label` for `action=%s`", action)
}
case "labelmap":
case "labelmap_all":
case "labeldrop":
case "labelkeep":
default:
return nil, fmt.Errorf("unknown `action` %q", action)
}
if action != "graphite" {
if graphiteMatchTemplate != nil {
return nil, fmt.Errorf("`match` config cannot be applied to `action=%s`; it is applied only to `action=graphite`", action)
}
if len(graphiteLabelRules) > 0 {
return nil, fmt.Errorf("`labels` config cannot be applied to `action=%s`; it is applied only to `action=graphite`", action)
}
}
return &parsedRelabelConfig{
SourceLabels: sourceLabels,
Separator: separator,
TargetLabel: targetLabel,
RegexAnchored: regexAnchored,
Modulus: modulus,
Replacement: replacement,
Action: action,
If: rc.If,
graphiteMatchTemplate: graphiteMatchTemplate,
graphiteLabelRules: graphiteLabelRules,
regex: promRegex,
regexOriginal: regexOriginalCompiled,
hasCaptureGroupInTargetLabel: strings.Contains(targetLabel, "$"),
hasCaptureGroupInReplacement: strings.Contains(replacement, "$"),
hasLabelReferenceInReplacement: strings.Contains(replacement, "{{"),
}, nil
}
func isDefaultRegex(expr string) bool {
prefix, suffix := regexutil.Simplify(expr)
if prefix != "" {
return false
}
return suffix == ".*"
}