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move fsm to sepeare pkg

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Signed-off-by: Wangchong Zhou <fffonion@gmail.com>
This commit is contained in:
Wangchong Zhou 2018-09-21 17:59:11 -07:00
parent a751c0c091
commit e634997791
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GPG key ID: B607274584E8D5E5
5 changed files with 452 additions and 371 deletions
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2
main.go
View file

@ -180,7 +180,7 @@ func main() {
mapper := &mapper.MetricMapper{MappingsCount: mappingsCount}
if *dumpFSMPath != "" {
err := mapper.SetDumpFSMPath(*dumpFSMPath)
err := mapper.FSM.SetDumpFSMPath(*dumpFSMPath)
if err != nil {
log.Fatal("Error setting dump FSM path:", err)
}

55
pkg/mapper/fsm/formatter.go Normal file
View file

@ -0,0 +1,55 @@
package fsm
import (
"fmt"
"strconv"
"strings"
)
type templateFormatter struct {
captureIndexes []int
captureCount int
fmtString string
}
func newTemplateFormatter(valueExpr string, captureCount int) *templateFormatter {
matches := templateReplaceCaptureRE.FindAllStringSubmatch(valueExpr, -1)
if len(matches) == 0 {
// if no regex reference found, keep it as it is
return &templateFormatter{captureCount: 0, fmtString: valueExpr}
}
var indexes []int
valueFormatter := valueExpr
for _, match := range matches {
idx, err := strconv.Atoi(match[len(match)-1])
if err != nil || idx > captureCount || idx < 1 {
// if index larger than captured count or using unsupported named capture group,
// replace with empty string
valueFormatter = strings.Replace(valueFormatter, match[0], "", -1)
} else {
valueFormatter = strings.Replace(valueFormatter, match[0], "%s", -1)
// note: the regex reference variable $? starts from 1
indexes = append(indexes, idx-1)
}
}
return &templateFormatter{
captureIndexes: indexes,
captureCount: len(indexes),
fmtString: valueFormatter,
}
}
func (formatter *templateFormatter) format(captures map[int]string) string {
if formatter.captureCount == 0 {
// no label substitution, keep as it is
return formatter.fmtString
} else {
indexes := formatter.captureIndexes
vargs := make([]interface{}, formatter.captureCount)
for i, idx := range indexes {
vargs[i] = captures[idx]
}
return fmt.Sprintf(formatter.fmtString, vargs...)
}
}

344
pkg/mapper/fsm/fsm.go Normal file
View file

@ -0,0 +1,344 @@
package fsm
import (
"bufio"
"fmt"
"os"
"regexp"
"strings"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/common/log"
)
var (
templateReplaceCaptureRE = regexp.MustCompile(`\$\{?([a-zA-Z0-9_\$]+)\}?`)
)
type mappingState struct {
transitions map[string]*mappingState
minRemainingLength int
maxRemainingLength int
// result* members are nil unless there's a metric ends with this state
result interface{}
resultPriority int
resultNameFormatter *templateFormatter
resultLabelsFormatter map[string]*templateFormatter
}
type fsmBacktrackStackCursor struct {
fieldIndex int
captureIndex int
currentCapture string
state *mappingState
prev *fsmBacktrackStackCursor
next *fsmBacktrackStackCursor
}
type FSM struct {
root *mappingState
needsBacktracking bool
dumpFSMPath string
metricTypes []string
disableOrdering bool
statesCount int
}
func (fsm *FSM) SetDumpFSMPath(path string) error {
fsm.dumpFSMPath = path
return nil
}
func NewFSM(metricTypes []string, maxPossibleTransitions int, disableOrdering bool) *FSM {
fsm := FSM{}
root := &mappingState{}
root.transitions = make(map[string]*mappingState, 3)
metricTypes = append(metricTypes, "")
for _, field := range metricTypes {
state := &mappingState{}
(*state).transitions = make(map[string]*mappingState, maxPossibleTransitions)
root.transitions[string(field)] = state
}
fsm.disableOrdering = disableOrdering
fsm.metricTypes = metricTypes
fsm.statesCount = 0
fsm.root = root
return &fsm
}
func (f *FSM) AddState(match string, name string, labels prometheus.Labels, matchMetricType string,
maxPossibleTransitions int, result interface{}) {
// first split by "."
matchFields := strings.Split(match, ".")
// fill into our FSM
roots := []*mappingState{}
if matchMetricType == "" {
// if metricType not specified, connect the state from all three types
for _, metricType := range f.metricTypes {
roots = append(roots, f.root.transitions[string(metricType)])
}
} else {
roots = append(roots, f.root.transitions[matchMetricType])
}
var captureCount int
var finalStates []*mappingState
for _, root := range roots {
captureCount = 0
for i, field := range matchFields {
state, prs := root.transitions[field]
if !prs {
state = &mappingState{}
(*state).transitions = make(map[string]*mappingState, maxPossibleTransitions)
(*state).maxRemainingLength = len(matchFields) - i - 1
(*state).minRemainingLength = len(matchFields) - i - 1
root.transitions[field] = state
// if this is last field, set result to currentMapping instance
if i == len(matchFields)-1 {
root.transitions[field].result = result
}
} else {
(*state).maxRemainingLength = max(len(matchFields)-i-1, (*state).maxRemainingLength)
(*state).minRemainingLength = min(len(matchFields)-i-1, (*state).minRemainingLength)
}
if field == "*" {
captureCount++
}
// goto next state
root = state
}
finalStates = append(finalStates, root)
}
nameFmt := newTemplateFormatter(name, captureCount)
currentLabelFormatter := make(map[string]*templateFormatter, captureCount)
for label, valueExpr := range labels {
lblFmt := newTemplateFormatter(valueExpr, captureCount)
currentLabelFormatter[label] = lblFmt
}
for _, state := range finalStates {
state.resultNameFormatter = nameFmt
state.resultLabelsFormatter = currentLabelFormatter
state.resultPriority = f.statesCount
}
f.statesCount++
}
func (f *FSM) DumpFSM() {
if f.dumpFSMPath == "" {
return
}
log.Infoln("Start dumping FSM to", f.dumpFSMPath)
idx := 0
states := make(map[int]*mappingState)
states[idx] = f.root
fd, _ := os.Create(f.dumpFSMPath)
w := bufio.NewWriter(fd)
w.WriteString("digraph g {\n")
w.WriteString("rankdir=LR\n") // make it vertical
w.WriteString("node [ label=\"\",style=filled,fillcolor=white,shape=circle ]\n") // remove label of node
for idx < len(states) {
for field, transition := range states[idx].transitions {
states[len(states)] = transition
w.WriteString(fmt.Sprintf("%d -> %d [label = \"%s\"];\n", idx, len(states)-1, field))
if idx == 0 {
// color for metric types
w.WriteString(fmt.Sprintf("%d [color=\"#D6B656\",fillcolor=\"#FFF2CC\"];\n", len(states)-1))
} else if transition.transitions == nil || len(transition.transitions) == 0 {
// color for end state
w.WriteString(fmt.Sprintf("%d [color=\"#82B366\",fillcolor=\"#D5E8D4\"];\n", len(states)-1))
}
}
idx++
}
// color for start state
w.WriteString(fmt.Sprintf("0 [color=\"#a94442\",fillcolor=\"#f2dede\"];\n"))
w.WriteString("}")
w.Flush()
log.Infoln("Finish dumping FSM")
}
func (f *FSM) TestIfNeedBacktracking(mappings []string) bool {
needBacktrack := false
// rule A and B that has same length and
// A one has * in rules but is not a superset of B makes it needed for backtracking
ruleByLength := make(map[int][]string)
ruleREByLength := make(map[int][]*regexp.Regexp)
// first sort rules by length
for _, mapping := range mappings {
l := len(strings.Split(mapping, "."))
ruleByLength[l] = append(ruleByLength[l], mapping)
metricRe := strings.Replace(mapping, ".", "\\.", -1)
metricRe = strings.Replace(metricRe, "*", "([^.]*)", -1)
regex, err := regexp.Compile("^" + metricRe + "$")
if err != nil {
log.Warnf("invalid match %s. cannot compile regex in mapping: %v", mapping, err)
}
// put into array no matter there's error or not, we will skip later if regex is nil
ruleREByLength[l] = append(ruleREByLength[l], regex)
}
for l, rules := range ruleByLength {
if len(rules) == 1 {
continue
}
rulesRE := ruleREByLength[l]
// for each rule r1 in rules that has * inside, check if r1 is the superset of any rules
// if not then r1 is a rule that leads to backtrack
for i1, r1 := range rules {
currentRuleNeedBacktrack := true
re1 := rulesRE[i1]
if re1 == nil || strings.Index(r1, "*") == -1 {
continue
}
for i2, r2 := range rules {
if i2 != i1 && len(re1.FindStringSubmatchIndex(r2)) > 0 {
// log if we care about ordering and the superset occurs before
if !f.disableOrdering && i1 < i2 {
log.Warnf("match \"%s\" is a super set of match \"%s\" but in a lower order, "+
"the first will never be matched\n", r1, r2)
}
currentRuleNeedBacktrack = false
}
}
for i2, re2 := range rulesRE {
// especially, if r1 is a subset of other rule, we don't need backtrack
// because either we turned on ordering
// or we disabled ordering and can't match it even with backtrack
if i2 != i1 && re2 != nil && len(re2.FindStringSubmatchIndex(r1)) > 0 {
currentRuleNeedBacktrack = false
}
}
if currentRuleNeedBacktrack {
log.Warnf("backtracking required because of match \"%s\", "+
"matching performance may be degraded\n", r1)
needBacktrack = true
}
}
}
// backtracking will always be needed if ordering of rules is not disabled
// since transistions are stored in (unordered) map
// note: don't move this branch to the beginning of this function
// since we need logs for superset rules
f.needsBacktracking = !f.disableOrdering || needBacktrack
return f.needsBacktracking
}
func (f *FSM) GetMapping(statsdMetric string, statsdMetricType string) (interface{}, string, prometheus.Labels, bool) {
matchFields := strings.Split(statsdMetric, ".")
currentState := f.root.transitions[statsdMetricType]
// the cursor/pointer in the backtrack stack
var backtrackCursor *fsmBacktrackStackCursor
resumeFromBacktrack := false
var finalState *mappingState
captures := make(map[int]string, len(matchFields))
captureIdx := 0
filedsCount := len(matchFields)
i := 0
var state *mappingState
for { // the loop for backtracking
for { // the loop for a single "depth only" search
var present bool
// if we resume from backtrack, we should skip this branch in this case
// since the state that were saved at the end of this branch
if !resumeFromBacktrack {
if len(currentState.transitions) > 0 {
field := matchFields[i]
state, present = currentState.transitions[field]
fieldsLeft := filedsCount - i - 1
// also compare length upfront to avoid unnecessary loop or backtrack
if !present || fieldsLeft > state.maxRemainingLength || fieldsLeft < state.minRemainingLength {
state, present = currentState.transitions["*"]
if !present || fieldsLeft > state.maxRemainingLength || fieldsLeft < state.minRemainingLength {
break
} else {
captures[captureIdx] = field
captureIdx++
}
} else if f.needsBacktracking {
altState, present := currentState.transitions["*"]
if !present || fieldsLeft > altState.maxRemainingLength || fieldsLeft < altState.minRemainingLength {
} else {
// push to backtracking stack
newCursor := fsmBacktrackStackCursor{prev: backtrackCursor, state: altState,
fieldIndex: i,
captureIndex: captureIdx, currentCapture: field,
}
if backtrackCursor != nil {
backtrackCursor.next = &newCursor
}
backtrackCursor = &newCursor
}
}
} else { // no more transitions for this state
break
}
} // backtrack will resume from here
// do we reach a final state?
if state.result != nil && i == filedsCount-1 {
if f.disableOrdering {
finalState = state
// do a double break
goto formatLabels
} else if finalState == nil || finalState.resultPriority > state.resultPriority {
// if we care about ordering, try to find a result with highest prioity
finalState = state
}
break
}
i++
if i >= filedsCount {
break
}
resumeFromBacktrack = false
currentState = state
}
if backtrackCursor == nil {
// if we are not doing backtracking or all path has been travesaled
break
} else {
// pop one from stack
state = backtrackCursor.state
currentState = state
i = backtrackCursor.fieldIndex
captureIdx = backtrackCursor.captureIndex + 1
// put the * capture back
captures[captureIdx-1] = backtrackCursor.currentCapture
backtrackCursor = backtrackCursor.prev
if backtrackCursor != nil {
// deref for GC
backtrackCursor.next = nil
}
resumeFromBacktrack = true
}
}
formatLabels:
// format name and labels
if finalState != nil {
name := finalState.resultNameFormatter.format(captures)
labels := prometheus.Labels{}
for key, formatter := range finalState.resultLabelsFormatter {
labels[key] = formatter.format(captures)
}
return finalState.result, name, labels, true
}
return nil, "", nil, false
}

17
pkg/mapper/fsm/minmax.go Normal file
View file

@ -0,0 +1,17 @@
package fsm
// min and max implementation for integer
func min(x, y int) int {
if x < y {
return x
}
return y
}
func max(x, y int) int {
if x > y {
return x
}
return y
}

405
pkg/mapper/mapper.go
View file

@ -14,17 +14,13 @@
package mapper
import (
"bufio"
"fmt"
"io/ioutil"
"os"
"regexp"
"strconv"
"strings"
"sync"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/common/log"
"github.com/prometheus/statsd_exporter/pkg/mapper/fsm"
yaml "gopkg.in/yaml.v2"
)
@ -40,59 +36,31 @@ var (
)
type mapperConfigDefaults struct {
TimerType TimerType `yaml:"timer_type"`
Buckets []float64 `yaml:"buckets"`
Quantiles []metricObjective `yaml:"quantiles"`
MatchType MatchType `yaml:"match_type"`
GlobDisbleOrdering bool `yaml:"glob_disable_ordering"`
}
type mappingState struct {
transitions map[string]*mappingState
minRemainingLength int
maxRemainingLength int
// result is nil unless there's a metric ends with this state
result *MetricMapping
TimerType TimerType `yaml:"timer_type"`
Buckets []float64 `yaml:"buckets"`
Quantiles []metricObjective `yaml:"quantiles"`
MatchType MatchType `yaml:"match_type"`
GlobDisableOrdering bool `yaml:"glob_disable_ordering"`
}
type MetricMapper struct {
Defaults mapperConfigDefaults `yaml:"defaults"`
Mappings []MetricMapping `yaml:"mappings"`
FSM *mappingState
hasFSM bool
FSMNeedsBacktracking bool
// if doRegex is true, at least one matching rule is regex type
doRegex bool
dumpFSMPath string
mutex sync.Mutex
Defaults mapperConfigDefaults `yaml:"defaults"`
Mappings []MetricMapping `yaml:"mappings"`
FSM *fsm.FSM
doFSM bool
doRegex bool
mutex sync.Mutex
MappingsCount prometheus.Gauge
}
type templateFormatter struct {
captureIndexes []int
captureCount int
fmtString string
}
type fsmBacktrackStackCursor struct {
fieldIndex int
captureIndex int
currentCapture string
state *mappingState
prev *fsmBacktrackStackCursor
next *fsmBacktrackStackCursor
}
type matchMetricType string
type MetricMapping struct {
Match string `yaml:"match"`
Name string `yaml:"name"`
NameFormatter templateFormatter
regex *regexp.Regexp
Labels prometheus.Labels `yaml:"labels"`
LabelsFormatter map[string]templateFormatter
TimerType TimerType `yaml:"timer_type"`
Buckets []float64 `yaml:"buckets"`
Quantiles []metricObjective `yaml:"quantiles"`
@ -100,7 +68,6 @@ type MetricMapping struct {
HelpText string `yaml:"help"`
Action ActionType `yaml:"action"`
MatchMetricType MetricType `yaml:"match_metric_type"`
priority int
}
type metricObjective struct {
@ -114,48 +81,6 @@ var defaultQuantiles = []metricObjective{
{Quantile: 0.99, Error: 0.001},
}
func generateFormatter(valueExpr string, captureCount int) templateFormatter {
matches := templateReplaceCaptureRE.FindAllStringSubmatch(valueExpr, -1)
if len(matches) == 0 {
// if no regex reference found, keep it as it is
return templateFormatter{captureCount: 0, fmtString: valueExpr}
}
var indexes []int
valueFormatter := valueExpr
for _, match := range matches {
idx, err := strconv.Atoi(match[len(match)-1])
if err != nil || idx > captureCount || idx < 1 {
// if index larger than captured count or using unsupported named capture group,
// replace with empty string
valueFormatter = strings.Replace(valueFormatter, match[0], "", -1)
} else {
valueFormatter = strings.Replace(valueFormatter, match[0], "%s", -1)
// note: the regex reference variable $? starts from 1
indexes = append(indexes, idx-1)
}
}
return templateFormatter{
captureIndexes: indexes,
captureCount: len(indexes),
fmtString: valueFormatter,
}
}
func formatTemplate(formatter templateFormatter, captures map[int]string) string {
if formatter.captureCount == 0 {
// no label substitution, keep as it is
return formatter.fmtString
} else {
indexes := formatter.captureIndexes
vargs := make([]interface{}, formatter.captureCount)
for i, idx := range indexes {
vargs[i] = captures[idx]
}
return fmt.Sprintf(formatter.fmtString, vargs...)
}
}
func min(x, y int) int {
if x < y {
return x
@ -189,18 +114,13 @@ func (m *MetricMapper) InitFromYAMLString(fileContents string) error {
n.Defaults.MatchType = MatchTypeGlob
}
maxPossibleTransitions := len(n.Mappings)
remainingMappingsCount := len(n.Mappings)
n.FSM = &mappingState{}
n.FSM.transitions = make(map[string]*mappingState, 3)
for _, field := range []MetricType{MetricTypeCounter, MetricTypeTimer, MetricTypeGauge, ""} {
state := &mappingState{}
(*state).transitions = make(map[string]*mappingState, maxPossibleTransitions)
n.FSM.transitions[string(field)] = state
}
n.FSM = fsm.NewFSM([]string{string(MetricTypeCounter), string(MetricTypeGauge), string(MetricTypeTimer)},
remainingMappingsCount, n.Defaults.GlobDisableOrdering)
for i := range n.Mappings {
maxPossibleTransitions--
remainingMappingsCount--
currentMapping := &n.Mappings[i]
@ -227,63 +147,15 @@ func (m *MetricMapper) InitFromYAMLString(fileContents string) error {
currentMapping.Action = ActionTypeMap
}
currentMapping.priority = i
if currentMapping.MatchType == MatchTypeGlob {
n.hasFSM = true
n.doFSM = true
if !metricLineRE.MatchString(currentMapping.Match) {
return fmt.Errorf("invalid match: %s", currentMapping.Match)
}
// first split by "."
matchFields := strings.Split(currentMapping.Match, ".")
// fill into our FSM
roots := []*mappingState{}
if currentMapping.MatchMetricType == "" {
// if metricType not specified, connect the state from all three types
for _, metricType := range []MetricType{MetricTypeCounter, MetricTypeTimer, MetricTypeGauge, ""} {
roots = append(roots, n.FSM.transitions[string(metricType)])
}
} else {
roots = append(roots, n.FSM.transitions[string(currentMapping.MatchMetricType)])
}
var captureCount int
for _, root := range roots {
captureCount = 0
for i, field := range matchFields {
state, prs := root.transitions[field]
if !prs {
state = &mappingState{}
(*state).transitions = make(map[string]*mappingState, maxPossibleTransitions)
(*state).maxRemainingLength = len(matchFields) - i - 1
(*state).minRemainingLength = len(matchFields) - i - 1
root.transitions[field] = state
// if this is last field, set result to currentMapping instance
if i == len(matchFields)-1 {
root.transitions[field].result = currentMapping
}
} else {
(*state).maxRemainingLength = max(len(matchFields)-i-1, (*state).maxRemainingLength)
(*state).minRemainingLength = min(len(matchFields)-i-1, (*state).minRemainingLength)
}
if field == "*" {
captureCount++
}
n.FSM.AddState(currentMapping.Match, currentMapping.Name, currentMapping.Labels, string(currentMapping.MatchMetricType),
remainingMappingsCount, currentMapping)
// goto next state
root = state
}
}
nameFmt := generateFormatter(currentMapping.Name, captureCount)
currentMapping.NameFormatter = nameFmt
currentLabelFormatter := make(map[string]templateFormatter, captureCount)
for label, valueExpr := range currentMapping.Labels {
lblFmt := generateFormatter(valueExpr, captureCount)
currentLabelFormatter[label] = lblFmt
}
currentMapping.LabelsFormatter = currentLabelFormatter
} else {
if regex, err := regexp.Compile(currentMapping.Match); err != nil {
return fmt.Errorf("invalid regex %s in mapping: %v", currentMapping.Match, err)
@ -312,16 +184,19 @@ func (m *MetricMapper) InitFromYAMLString(fileContents string) error {
m.Defaults = n.Defaults
m.Mappings = n.Mappings
m.hasFSM = n.hasFSM
if n.hasFSM {
if n.doFSM {
var mappings []string
for _, mapping := range n.Mappings {
if mapping.MatchType == MatchTypeGlob {
mappings = append(mappings, mapping.Match)
}
}
n.FSM.TestIfNeedBacktracking(mappings)
m.FSM = n.FSM
m.doRegex = n.doRegex
if m.dumpFSMPath != "" {
dumpFSM(m.dumpFSMPath, m.FSM)
}
m.FSMNeedsBacktracking = needBacktracking(&n)
}
m.doFSM = n.doFSM
if m.MappingsCount != nil {
m.MappingsCount.Set(float64(len(n.Mappings)))
@ -330,121 +205,6 @@ func (m *MetricMapper) InitFromYAMLString(fileContents string) error {
return nil
}
func (m *MetricMapper) SetDumpFSMPath(path string) error {
m.dumpFSMPath = path
return nil
}
func needBacktracking(n *MetricMapper) bool {
needBacktrack := false
// rule A and B that has same length and
// A one has * in rules but is not a superset of B makes it needed for backtracking
ruleByLength := make(map[int][]string)
ruleREByLength := make(map[int][]*regexp.Regexp)
rulesOrderByLength := make(map[int][]int)
// first sort rules by length
for _, mapping := range n.Mappings {
if mapping.MatchType != MatchTypeGlob {
continue
}
l := len(strings.Split(mapping.Match, "."))
ruleByLength[l] = append(ruleByLength[l], mapping.Match)
metricRe := strings.Replace(mapping.Match, ".", "\\.", -1)
metricRe = strings.Replace(metricRe, "*", "([^.]*)", -1)
regex, err := regexp.Compile("^" + metricRe + "$")
if err != nil {
log.Warnf("invalid match %s. cannot compile regex in mapping: %v", mapping.Match, err)
}
// put into array no matter there's error or not, we will skip later if regex is nil
ruleREByLength[l] = append(ruleREByLength[l], regex)
rulesOrderByLength[l] = append(rulesOrderByLength[l], mapping.priority)
}
for l, rules := range ruleByLength {
if len(rules) == 1 {
continue
}
rulesRE := ruleREByLength[l]
rulesOrder := rulesOrderByLength[l]
// for each rule r1 in rules that has * inside, check if r1 is the superset of any rules
// if not then r1 is a rule that leads to backtrack
for i1, r1 := range rules {
currentRuleNeedBacktrack := true
re1 := rulesRE[i1]
if re1 == nil || strings.Index(r1, "*") == -1 {
continue
}
for i2, r2 := range rules {
if i2 != i1 && len(re1.FindStringSubmatchIndex(r2)) > 0 {
// log if we care about ordering and the superset occurs before
if !n.Defaults.GlobDisbleOrdering && rulesOrder[i1] < rulesOrder[i2] {
log.Warnf("match \"%s\" is a super set of match \"%s\" but in a lower order, "+
"the first will never be matched\n", r1, r2)
}
currentRuleNeedBacktrack = false
}
}
for i2, re2 := range rulesRE {
// especially, if r1 is a subset of other rule, we don't need backtrack
// because either we turned on ordering
// or we disabled ordering and can't match it even with backtrack
if i2 != i1 && re2 != nil && len(re2.FindStringSubmatchIndex(r1)) > 0 {
currentRuleNeedBacktrack = false
}
}
if currentRuleNeedBacktrack {
log.Warnf("backtracking required because of match \"%s\", "+
"matching performance may be degraded\n", r1)
needBacktrack = true
}
}
}
if !n.Defaults.GlobDisbleOrdering {
// backtracking only makes sense when we disbled ordering of rules
// where transistions are stored in (unordered) map
// note: don't move this branch to the beginning of this function
// since we need logs for superset rules
return true
} else {
return needBacktrack
}
}
func dumpFSM(fileName string, root *mappingState) {
log.Infoln("Start dumping FSM to", fileName)
idx := 0
states := make(map[int]*mappingState)
states[idx] = root
f, _ := os.Create(fileName)
w := bufio.NewWriter(f)
w.WriteString("digraph g {\n")
w.WriteString("rankdir=LR\n") // make it vertical
w.WriteString("node [ label=\"\",style=filled,fillcolor=white,shape=circle ]\n") // remove label of node
for idx < len(states) {
for field, transition := range states[idx].transitions {
states[len(states)] = transition
w.WriteString(fmt.Sprintf("%d -> %d [label = \"%s\"];\n", idx, len(states)-1, field))
if idx == 0 {
// color for metric types
w.WriteString(fmt.Sprintf("%d [color=\"#D6B656\",fillcolor=\"#FFF2CC\"];\n", len(states)-1))
} else if transition.transitions == nil || len(transition.transitions) == 0 {
// color for end state
w.WriteString(fmt.Sprintf("%d [color=\"#82B366\",fillcolor=\"#D5E8D4\"];\n", len(states)-1))
}
}
idx++
}
// color for start state
w.WriteString(fmt.Sprintf("0 [color=\"#a94442\",fillcolor=\"#f2dede\"];\n"))
w.WriteString("}")
w.Flush()
log.Infoln("Finish dumping FSM")
}
func (m *MetricMapper) InitFromFile(fileName string) error {
mappingStr, err := ioutil.ReadFile(fileName)
if err != nil {
@ -455,110 +215,15 @@ func (m *MetricMapper) InitFromFile(fileName string) error {
func (m *MetricMapper) GetMapping(statsdMetric string, statsdMetricType MetricType) (*MetricMapping, prometheus.Labels, bool) {
// glob matching
if m.hasFSM {
matchFields := strings.Split(statsdMetric, ".")
root := m.FSM.transitions[string(statsdMetricType)]
captures := make(map[int]string, len(matchFields))
captureIdx := 0
var backtrackCursor *fsmBacktrackStackCursor
resumeFromBacktrack := false
var result *MetricMapping
filedsCount := len(matchFields)
i := 0
var state *mappingState
for {
for {
var prs bool
if !resumeFromBacktrack {
if len(root.transitions) > 0 {
field := matchFields[i]
state, prs = root.transitions[field]
fieldsLeft := filedsCount - i - 1
// also compare length upfront to avoid unnecessary loop or backtrack
if !prs || fieldsLeft > state.maxRemainingLength || fieldsLeft < state.minRemainingLength {
state, prs = root.transitions["*"]
if !prs || fieldsLeft > state.maxRemainingLength || fieldsLeft < state.minRemainingLength {
break
} else {
captures[captureIdx] = field
captureIdx++
}
} else if m.FSMNeedsBacktracking {
altState, prs := root.transitions["*"]
if !prs || fieldsLeft > altState.maxRemainingLength || fieldsLeft < altState.minRemainingLength {
} else {
// push to stack
newCursor := fsmBacktrackStackCursor{prev: backtrackCursor, state: altState,
fieldIndex: i,
captureIndex: captureIdx, currentCapture: field,
}
if backtrackCursor != nil {
backtrackCursor.next = &newCursor
}
backtrackCursor = &newCursor
}
}
} else { // no more transitions for this state
break
}
} // backtrack will resume from here
// do we reach a final state?
if state.result != nil && i == filedsCount-1 {
if m.Defaults.GlobDisbleOrdering {
result = state.result
// do a double break
goto formatLabels
} else if result == nil || result.priority > state.result.priority {
// if we care about ordering, try to find a result with highest prioity
result = state.result
}
break
}
i++
if i >= filedsCount {
break
}
resumeFromBacktrack = false
root = state
}
if backtrackCursor == nil {
// if we are not doing backtracking or all path has been travesaled
break
} else {
// pop one from stack
state = backtrackCursor.state
root = state
i = backtrackCursor.fieldIndex
captureIdx = backtrackCursor.captureIndex + 1
// put the * capture back
captures[captureIdx-1] = backtrackCursor.currentCapture
backtrackCursor = backtrackCursor.prev
if backtrackCursor != nil {
// deref for GC
backtrackCursor.next = nil
}
resumeFromBacktrack = true
}
}
formatLabels:
// format name and labels
if result != nil {
result.Name = formatTemplate(result.NameFormatter, captures)
labels := prometheus.Labels{}
for label := range result.Labels {
labels[label] = formatTemplate(result.LabelsFormatter[label], captures)
}
return result, labels, true
} else if !m.doRegex {
if m.doFSM {
mapping, mappingName, labels, matched := m.FSM.GetMapping(statsdMetric, string(statsdMetricType))
if matched {
mapping.(*MetricMapping).Name = mappingName
return mapping.(*MetricMapping), labels, matched
} else if !matched && !m.doRegex {
// if there's no regex match type, return immediately
return nil, nil, false
}
}
// regex matching