Extract labels package

cmd/tsdb/main.go

@@ -14,6 +14,7 @@ import (
 	"time"
 
 	"github.com/fabxc/tsdb"
+	"github.com/fabxc/tsdb/labels"
 	dto "github.com/prometheus/client_model/go"
 	"github.com/prometheus/common/expfmt"
 	"github.com/prometheus/common/model"
@@ -162,16 +163,16 @@ func (b *writeBenchmark) ingestScrapesShard(metrics []model.Metric, scrapeCount
 	ts := int64(model.Now())
 
 	type sample struct {
-		labels tsdb.Labels
+		labels labels.Labels
 		value  int64
 	}
 
 	scrape := make(map[uint64]*sample, len(metrics))
 
 	for _, m := range metrics {
-		lset := make(tsdb.Labels, 0, len(m))
+		lset := make(labels.Labels, 0, len(m))
 		for k, v := range m {
-			lset = append(lset, tsdb.Label{Name: string(k), Value: string(v)})
+			lset = append(lset, labels.Label{Name: string(k), Value: string(v)})
 		}
 		sort.Sort(lset)
 

db.go

@@ -7,7 +7,6 @@ import (
 	"os"
 	"path/filepath"
 	"reflect"
-	"sort"
 	"strconv"
 	"sync"
 	"time"
@@ -15,8 +14,8 @@ import (
 
 	"golang.org/x/sync/errgroup"
 
-	"github.com/cespare/xxhash"
 	"github.com/fabxc/tsdb/chunks"
+	"github.com/fabxc/tsdb/labels"
 	"github.com/go-kit/kit/log"
 )
 
@@ -112,7 +111,7 @@ type Appender interface {
 	// AddSeries(Labels) uint64
 
 	// Add adds a sample pair for the referenced series.
-	Add(lset Labels, t int64, v float64)
+	Add(lset labels.Labels, t int64, v float64)
 
 	// Commit submits the collected samples and purges the batch.
 	Commit() error
@@ -131,7 +130,7 @@ type bucketAppender struct {
 	buckets [][]hashedSample
 }
 
-func (ba *bucketAppender) Add(lset Labels, t int64, v float64) {
+func (ba *bucketAppender) Add(lset labels.Labels, t int64, v float64) {
 	h := lset.Hash()
 	s := h >> (64 - shardShift)
 
@@ -163,7 +162,7 @@ func (ba *bucketAppender) Commit() error {
 
 type hashedSample struct {
 	hash   uint64
-	labels Labels
+	labels labels.Labels
 
 	t int64
 	v float64
@@ -334,7 +333,7 @@ func (s *Shard) persist() error {
 
 // chunkDesc wraps a plain data chunk and provides cached meta data about it.
 type chunkDesc struct {
-	lset  Labels
+	lset  labels.Labels
 	chunk chunks.Chunk
 
 	// Caching fields.
@@ -363,86 +362,6 @@ func (cd *chunkDesc) append(ts int64, v float64) (err error) {
 	return nil
 }
 
-// Label is a key/value pair of strings.
-type Label struct {
-	Name, Value string
-}
-
-// Labels is a sorted set of labels. Order has to be guaranteed upon
-// instantiation.
-type Labels []Label
-
-func (ls Labels) Len() int           { return len(ls) }
-func (ls Labels) Swap(i, j int)      { ls[i], ls[j] = ls[j], ls[i] }
-func (ls Labels) Less(i, j int) bool { return ls[i].Name < ls[j].Name }
-
-// Hash returns a hash value for the label set.
-func (ls Labels) Hash() uint64 {
-	b := make([]byte, 0, 1024)
-
-	for _, v := range ls {
-		b = append(b, v.Name...)
-		b = append(b, sep)
-		b = append(b, v.Value...)
-		b = append(b, sep)
-	}
-	return xxhash.Sum64(b)
-}
-
-// Get returns the value for the label with the given name.
-// Returns an empty string if the label doesn't exist.
-func (ls Labels) Get(name string) string {
-	for _, l := range ls {
-		if l.Name == name {
-			return l.Value
-		}
-	}
-	return ""
-}
-
-// Equals returns whether the two label sets are equal.
-func (ls Labels) Equals(o Labels) bool {
-	if len(ls) != len(o) {
-		return false
-	}
-	for i, l := range ls {
-		if l.Name != o[i].Name || l.Value != o[i].Value {
-			return false
-		}
-	}
-	return true
-}
-
-// Map returns a string map of the labels.
-func (ls Labels) Map() map[string]string {
-	m := make(map[string]string, len(ls))
-	for _, l := range ls {
-		m[l.Name] = l.Value
-	}
-	return m
-}
-
-// NewLabels returns a sorted Labels from the given labels.
-// The caller has to guarantee that all label names are unique.
-func NewLabels(ls ...Label) Labels {
-	set := make(Labels, 0, len(ls))
-	for _, l := range ls {
-		set = append(set, l)
-	}
-	sort.Sort(set)
-
-	return set
-}
-
-// LabelsFromMap returns new sorted Labels from the given map.
-func LabelsFromMap(m map[string]string) Labels {
-	l := make([]Label, 0, len(m))
-	for k, v := range m {
-		l = append(l, Label{Name: k, Value: v})
-	}
-	return NewLabels(l...)
-}
-
 // The MultiError type implements the error interface, and contains the
 // Errors used to construct it.
 type MultiError []error

head.go

@@ -7,6 +7,7 @@ import (
 	"sync"
 
 	"github.com/fabxc/tsdb/chunks"
+	"github.com/fabxc/tsdb/labels"
 )
 
 // HeadBlock handles reads and writes of time series data within a time window.
@@ -99,7 +100,7 @@ func (h *HeadBlock) Series(ref uint32, mint, maxt int64) (Series, error) {
 
 // get retrieves the chunk with the hash and label set and creates
 // a new one if it doesn't exist yet.
-func (h *HeadBlock) get(hash uint64, lset Labels) *chunkDesc {
+func (h *HeadBlock) get(hash uint64, lset labels.Labels) *chunkDesc {
 	cds := h.descs[hash]
 	for _, cd := range cds {
 		if cd.lset.Equals(lset) {
@@ -122,7 +123,7 @@ func (h *HeadBlock) get(hash uint64, lset Labels) *chunkDesc {
 }
 
 // append adds the sample to the headblock.
-func (h *HeadBlock) append(hash uint64, lset Labels, ts int64, v float64) error {
+func (h *HeadBlock) append(hash uint64, lset labels.Labels, ts int64, v float64) error {
 	if err := h.get(hash, lset).append(ts, v); err != nil {
 		return err
 	}

labels/labels.go

@@ -0,0 +1,89 @@
+package labels
+
+import (
+	"sort"
+
+	"github.com/cespare/xxhash"
+)
+
+const sep = '\xff'
+
+// Label is a key/value pair of strings.
+type Label struct {
+	Name, Value string
+}
+
+// Labels is a sorted set of labels. Order has to be guaranteed upon
+// instantiation.
+type Labels []Label
+
+func (ls Labels) Len() int           { return len(ls) }
+func (ls Labels) Swap(i, j int)      { ls[i], ls[j] = ls[j], ls[i] }
+func (ls Labels) Less(i, j int) bool { return ls[i].Name < ls[j].Name }
+
+// Hash returns a hash value for the label set.
+func (ls Labels) Hash() uint64 {
+	b := make([]byte, 0, 1024)
+
+	for _, v := range ls {
+		b = append(b, v.Name...)
+		b = append(b, sep)
+		b = append(b, v.Value...)
+		b = append(b, sep)
+	}
+	return xxhash.Sum64(b)
+}
+
+// Get returns the value for the label with the given name.
+// Returns an empty string if the label doesn't exist.
+func (ls Labels) Get(name string) string {
+	for _, l := range ls {
+		if l.Name == name {
+			return l.Value
+		}
+	}
+	return ""
+}
+
+// Equals returns whether the two label sets are equal.
+func (ls Labels) Equals(o Labels) bool {
+	if len(ls) != len(o) {
+		return false
+	}
+	for i, l := range ls {
+		if l.Name != o[i].Name || l.Value != o[i].Value {
+			return false
+		}
+	}
+	return true
+}
+
+// Map returns a string map of the labels.
+func (ls Labels) Map() map[string]string {
+	m := make(map[string]string, len(ls))
+	for _, l := range ls {
+		m[l.Name] = l.Value
+	}
+	return m
+}
+
+// NewLabels returns a sorted Labels from the given labels.
+// The caller has to guarantee that all label names are unique.
+func NewLabels(ls ...Label) Labels {
+	set := make(Labels, 0, len(ls))
+	for _, l := range ls {
+		set = append(set, l)
+	}
+	sort.Sort(set)
+
+	return set
+}
+
+// LabelsFromMap returns new sorted Labels from the given map.
+func LabelsFromMap(m map[string]string) Labels {
+	l := make([]Label, 0, len(m))
+	for k, v := range m {
+		l = append(l, Label{Name: k, Value: v})
+	}
+	return NewLabels(l...)
+}

labels/selector.go

@@ -0,0 +1,68 @@
+package labels
+
+import "regexp"
+
+// Selector holds constraints for matching against a label set.
+type Selector []Matcher
+
+// Matches returns whether the labels satisfy all matchers.
+func (s Selector) Matches(labels Labels) bool {
+	for _, m := range s {
+		if v := labels.Get(m.Name()); !m.Matches(v) {
+			return false
+		}
+	}
+	return true
+}
+
+// Matcher specifies a constraint for the value of a label.
+type Matcher interface {
+	// Name returns the label name the matcher should apply to.
+	Name() string
+	// Matches checks whether a value fulfills the constraints.
+	Matches(v string) bool
+}
+
+type equalMatcher struct {
+	name, value string
+}
+
+func (m *equalMatcher) Name() string          { return m.name }
+func (m *equalMatcher) Matches(v string) bool { return v == m.value }
+
+// NewEqualMatcher returns a new matcher matching an exact label value.
+func NewEqualMatcher(name, value string) Matcher {
+	return &equalMatcher{name: name, value: value}
+}
+
+type regexpMatcher struct {
+	name string
+	re   *regexp.Regexp
+}
+
+func (m *regexpMatcher) Name() string          { return m.name }
+func (m *regexpMatcher) Matches(v string) bool { return m.re.MatchString(v) }
+
+// NewRegexpMatcher returns a new matcher verifying that a value matches
+// the regular expression pattern.
+func NewRegexpMatcher(name, pattern string) (Matcher, error) {
+	re, err := regexp.Compile(pattern)
+	if err != nil {
+		return nil, err
+	}
+	return &regexpMatcher{name: name, re: re}, nil
+}
+
+// notMatcher inverts the matching result for a matcher.
+type notMatcher struct {
+	Matcher
+}
+
+func (m *notMatcher) Matches(v string) bool {
+	return !m.Matcher.Matches(v)
+}
+
+// Not inverts the matcher's matching result.
+func Not(m Matcher) Matcher {
+	return &notMatcher{m}
+}

querier.go

@@ -7,38 +7,20 @@ import (
 	"strings"
 
 	"github.com/fabxc/tsdb/chunks"
+	"github.com/fabxc/tsdb/labels"
 )
 
-// Matcher matches a string.
-type Matcher interface {
-	Name() string
-	// Match returns true if the matcher applies to the string value.
-	Match(v string) bool
-}
-
-type equalMatcher struct {
-	name  string
-	value string
-}
-
-func MatchEquals(n, v string) Matcher {
-	return &equalMatcher{name: n, value: v}
-}
-
-func (m *equalMatcher) Name() string        { return m.name }
-func (m *equalMatcher) Match(v string) bool { return v == m.value }
-
 // Querier provides querying access over time series data of a fixed
 // time range.
 type Querier interface {
 	// Select returns a set of series that matches the given label matchers.
-	Select(...Matcher) SeriesSet
+	Select(...labels.Matcher) SeriesSet
 
 	// LabelValues returns all potential values for a label name.
 	LabelValues(string) ([]string, error)
 	// LabelValuesFor returns all potential values for a label name.
 	// under the constraint of another label.
-	LabelValuesFor(string, Label) ([]string, error)
+	LabelValuesFor(string, labels.Label) ([]string, error)
 
 	// Close releases the resources of the Querier.
 	Close() error
@@ -47,7 +29,7 @@ type Querier interface {
 // Series represents a single time series.
 type Series interface {
 	// Labels returns the complete set of labels identifying the series.
-	Labels() Labels
+	Labels() labels.Labels
 
 	// Iterator returns a new iterator of the data of the series.
 	Iterator() SeriesIterator
@@ -75,7 +57,7 @@ func (db *DB) Querier(mint, maxt int64) Querier {
 	return q
 }
 
-func (q *querier) Select(ms ...Matcher) SeriesSet {
+func (q *querier) Select(ms ...labels.Matcher) SeriesSet {
 	// We gather the non-overlapping series from every shard and simply
 	// return their union.
 	r := &mergedSeriesSet{}
@@ -134,7 +116,7 @@ func mergeStrings(a, b []string) []string {
 	return res
 }
 
-func (q *querier) LabelValuesFor(string, Label) ([]string, error) {
+func (q *querier) LabelValuesFor(string, labels.Label) ([]string, error) {
 	return nil, fmt.Errorf("not implemented")
 }
 
@@ -180,11 +162,11 @@ func (q *shardQuerier) LabelValues(n string) ([]string, error) {
 	return res, nil
 }
 
-func (q *shardQuerier) LabelValuesFor(string, Label) ([]string, error) {
+func (q *shardQuerier) LabelValuesFor(string, labels.Label) ([]string, error) {
 	return nil, fmt.Errorf("not implemented")
 }
 
-func (q *shardQuerier) Select(ms ...Matcher) SeriesSet {
+func (q *shardQuerier) Select(ms ...labels.Matcher) SeriesSet {
 	// Sets from different blocks have no time overlap. The reference numbers
 	// they emit point to series sorted in lexicographic order.
 	// We can fully connect partial series by simply comparing with the previous
@@ -221,7 +203,7 @@ func newBlockQuerier(ix IndexReader, s SeriesReader, mint, maxt int64) *blockQue
 	}
 }
 
-func (q *blockQuerier) Select(ms ...Matcher) SeriesSet {
+func (q *blockQuerier) Select(ms ...labels.Matcher) SeriesSet {
 	var its []Postings
 	for _, m := range ms {
 		its = append(its, q.selectSingle(m))
@@ -235,7 +217,7 @@ func (q *blockQuerier) Select(ms ...Matcher) SeriesSet {
 	}
 }
 
-func (q *blockQuerier) selectSingle(m Matcher) Postings {
+func (q *blockQuerier) selectSingle(m labels.Matcher) Postings {
 	tpls, err := q.index.LabelValues(m.Name())
 	if err != nil {
 		return errPostings{err: err}
@@ -249,7 +231,7 @@ func (q *blockQuerier) selectSingle(m Matcher) Postings {
 		if err != nil {
 			return errPostings{err: err}
 		}
-		if m.Match(vals[0]) {
+		if m.Matches(vals[0]) {
 			res = append(res, vals[0])
 		}
 	}
@@ -295,7 +277,7 @@ func (q *blockQuerier) LabelValues(name string) ([]string, error) {
 	return res, nil
 }
 
-func (q *blockQuerier) LabelValuesFor(string, Label) ([]string, error) {
+func (q *blockQuerier) LabelValuesFor(string, labels.Label) ([]string, error) {
 	return nil, fmt.Errorf("not implemented")
 }
 
@@ -360,7 +342,7 @@ func newShardSeriesSet(a, b SeriesSet) *shardSeriesSet {
 
 // compareLabels compares the two label sets.
 // The result will be 0 if a==b, <0 if a < b, and >0 if a > b.
-func compareLabels(a, b Labels) int {
+func compareLabels(a, b labels.Labels) int {
 	l := len(a)
 	if len(b) < l {
 		l = len(b)
@@ -475,7 +457,7 @@ func (s *blockSeriesSet) Err() error     { return s.err }
 // chunkSeries is a series that is backed by a sequence of chunks holding
 // time series data.
 type chunkSeries struct {
-	labels Labels
+	labels labels.Labels
 	chunks []ChunkMeta // in-order chunk refs
 
 	// chunk is a function that retrieves chunks based on a reference
@@ -483,7 +465,7 @@ type chunkSeries struct {
 	chunk func(ref uint32) (chunks.Chunk, error)
 }
 
-func (s *chunkSeries) Labels() Labels {
+func (s *chunkSeries) Labels() labels.Labels {
 	return s.labels
 }
 
@@ -525,7 +507,7 @@ type chainedSeries struct {
 	series []Series
 }
 
-func (s *chainedSeries) Labels() Labels {
+func (s *chainedSeries) Labels() labels.Labels {
 	return s.series[0].Labels()
 }
 

reader.go

@@ -6,6 +6,7 @@ import (
 	"strings"
 
 	"github.com/fabxc/tsdb/chunks"
+	"github.com/fabxc/tsdb/labels"
 	"github.com/pkg/errors"
 )
 
@@ -269,7 +270,7 @@ func (r *indexReader) Series(ref uint32, mint, maxt int64) (Series, error) {
 	//
 	// The references are expected to be sorted and match the order of
 	// the underlying strings.
-	labels := make(Labels, 0, k)
+	lbls := make(labels.Labels, 0, k)
 
 	for i := 0; i < len(offsets); i += 2 {
 		n, err := r.lookupSymbol(offsets[i])
@@ -280,7 +281,7 @@ func (r *indexReader) Series(ref uint32, mint, maxt int64) (Series, error) {
 		if err != nil {
 			return nil, errors.Wrap(err, "symbol lookup")
 		}
-		labels = append(labels, Label{
+		lbls = append(lbls, labels.Label{
 			Name:  string(n),
 			Value: string(v),
 		})
@@ -337,7 +338,7 @@ func (r *indexReader) Series(ref uint32, mint, maxt int64) (Series, error) {
 	}
 
 	return &chunkSeries{
-		labels: labels,
+		labels: lbls,
 		chunks: chunks,
 		chunk:  r.series.Chunk,
 	}, nil

test/labels_test.go

@@ -10,12 +10,15 @@ import (
 
 func BenchmarkLabelMapAccess(b *testing.B) {
 	m := map[string]string{
-		"job":       "node",
+		"job":        "node",
-		"instance":  "123.123.1.211:9090",
+		"instance":   "123.123.1.211:9090",
-		"path":      "/api/v1/namespaces/<namespace>/deployments/<name>",
+		"path":       "/api/v1/namespaces/<namespace>/deployments/<name>",
-		"method":    "GET",
+		"method":     "GET",
-		"namespace": "system",
+		"namespace":  "system",
-		"status":    "500",
+		"status":     "500",
+		"prometheus": "prometheus-core-1",
+		"datacenter": "eu-west-1",
+		"pod_name":   "abcdef-99999-defee",
 	}
 
 	var v string
@@ -33,12 +36,15 @@ func BenchmarkLabelMapAccess(b *testing.B) {
 
 func BenchmarkLabelSetAccess(b *testing.B) {
 	m := map[string]string{
-		"job":       "node",
+		"job":        "node",
-		"instance":  "123.123.1.211:9090",
+		"instance":   "123.123.1.211:9090",
-		"path":      "/api/v1/namespaces/<namespace>/deployments/<name>",
+		"path":       "/api/v1/namespaces/<namespace>/deployments/<name>",
-		"method":    "GET",
+		"method":     "GET",
-		"namespace": "system",
+		"namespace":  "system",
-		"status":    "500",
+		"status":     "500",
+		"prometheus": "prometheus-core-1",
+		"datacenter": "eu-west-1",
+		"pod_name":   "abcdef-99999-defee",
 	}
 	ls := tsdb.LabelsFromMap(m)
 

writer.go

@@ -10,6 +10,7 @@ import (
 	"strings"
 
 	"github.com/bradfitz/slice"
+	"github.com/fabxc/tsdb/labels"
 	"github.com/pkg/errors"
 )
 
@@ -26,7 +27,7 @@ type SeriesWriter interface {
 	// WriteSeries writes the time series data chunks for a single series.
 	// The reference is used to resolve the correct series in the written index.
 	// It only has to be valid for the duration of the write.
-	WriteSeries(ref uint32, l Labels, cds []*chunkDesc) error
+	WriteSeries(ref uint32, l labels.Labels, cds []*chunkDesc) error
 
 	// Size returns the size of the data written so far.
 	Size() int64
@@ -71,7 +72,7 @@ func (w *seriesWriter) writeMeta() error {
 	return w.write(w.w, b[:])
 }
 
-func (w *seriesWriter) WriteSeries(ref uint32, lset Labels, chks []*chunkDesc) error {
+func (w *seriesWriter) WriteSeries(ref uint32, lset labels.Labels, chks []*chunkDesc) error {
 	// Initialize with meta data.
 	if w.n == 0 {
 		if err := w.writeMeta(); err != nil {
@@ -156,7 +157,7 @@ type IndexWriter interface {
 	// of chunks that the index can reference.
 	// The reference number is used to resolve a series against the postings
 	// list iterator. It only has to be available during the write processing.
-	AddSeries(ref uint32, l Labels, chunks ...ChunkMeta)
+	AddSeries(ref uint32, l labels.Labels, chunks ...ChunkMeta)
 
 	// WriteStats writes final stats for the indexed block.
 	WriteStats(BlockStats) error
@@ -177,7 +178,7 @@ type IndexWriter interface {
 }
 
 type indexWriterSeries struct {
-	labels Labels
+	labels labels.Labels
 	chunks []ChunkMeta // series file offset of chunks
 	offset uint32      // index file offset of series reference
 }
@@ -240,7 +241,7 @@ func (w *indexWriter) writeMeta() error {
 	return w.write(w.w, b[:])
 }
 
-func (w *indexWriter) AddSeries(ref uint32, lset Labels, chunks ...ChunkMeta) {
+func (w *indexWriter) AddSeries(ref uint32, lset labels.Labels, chunks ...ChunkMeta) {
 	// Populate the symbol table from all label sets we have to reference.
 	for _, l := range lset {
 		w.symbols[l.Name] = 0