Address feedback

filters/tags_filter.go

@@ -47,7 +47,7 @@ func (tn tagFiltersByNameAsc) Less(i, j int) bool { return bytes.Compare(tn[i].n
 // TagsFilterOptions provide a set of tag filter options.
 type TagsFilterOptions struct {
 	// Name of the name tag.
-	NameTagName []byte
+	NameTagKey []byte
 
 	// Function to extract name and tags from an id.
 	NameAndTagsFn id.NameAndTagsFn
@@ -80,7 +80,7 @@ func NewTagsFilter(
 			return nil, err
 		}
 		bName := []byte(name)
-		if bytes.Equal(opts.NameTagName, bName) {
+		if bytes.Equal(opts.NameTagKey, bName) {
 			nameFilter = valFilter
 		} else {
 			tagFilters = append(tagFilters, tagFilter{
@@ -103,7 +103,7 @@ func (f *tagsFilter) String() string {
 	var buf bytes.Buffer
 	numTagFilters := len(f.tagFilters)
 	if f.nameFilter != nil {
-		buf.WriteString(fmt.Sprintf("%s:%s", f.opts.NameTagName, f.nameFilter.String()))
+		buf.WriteString(fmt.Sprintf("%s:%s", f.opts.NameTagKey, f.nameFilter.String()))
 		if numTagFilters > 0 {
 			buf.WriteString(separator)
 		}

filters/tags_filter_test.go

@@ -84,7 +84,7 @@ func TestTagsFilterString(t *testing.T) {
 
 func testTagsFilterOptions() TagsFilterOptions {
 	return TagsFilterOptions{
-		NameTagName:         []byte("name"),
+		NameTagKey:          []byte("name"),
 		NameAndTagsFn:       func(b []byte) ([]byte, []byte, error) { return nil, b, nil },
 		SortedTagIteratorFn: NewMockSortedTagIterator,
 	}

metric/id/id.go

@@ -32,7 +32,7 @@ type ID interface {
 }
 
 // NameAndTagsFn returns the name and the tag pairs given an id.
-type NameAndTagsFn func(id []byte) ([]byte, []byte, error)
+type NameAndTagsFn func(id []byte) (name []byte, tags []byte, err error)
 
 // NewIDFn creates a new metric ID based on the metric name and metric tag pairs.
 type NewIDFn func(name []byte, tags []TagPair) []byte

metric/id/m3/id.go

@@ -48,7 +48,6 @@ const (
 var (
 	errInvalidM3Metric = fmt.Errorf("invalid m3 metric")
 	m3Prefix           = []byte("m3+")
-	nameTagName        = []byte("name")
 	rollupTagPair      = id.TagPair{
 		Name:  []byte("m3_rollup"),
 		Value: []byte("true"),
@@ -80,25 +79,26 @@ func NewRollupID(name []byte, tagPairs []id.TagPair) []byte {
 }
 
 // TODO(xichen): pool the mids.
-type mid struct {
-	id     []byte
-	iterFn id.SortedTagIteratorFn
+type metricID struct {
+	id       []byte
+	iterPool id.SortedTagIteratorPool
 }
 
 // NewID creates a new m3 metric id.
-func NewID(id []byte, iterFn id.SortedTagIteratorFn) id.ID {
-	return mid{id: id, iterFn: iterFn}
+func NewID(id []byte, iterPool id.SortedTagIteratorPool) id.ID {
+	return metricID{id: id, iterPool: iterPool}
 }
 
-func (id mid) Bytes() []byte { return id.id }
+func (id metricID) Bytes() []byte { return id.id }
 
-func (id mid) TagValue(tagName []byte) ([]byte, bool) {
+func (id metricID) TagValue(tagName []byte) ([]byte, bool) {
 	_, tagPairs, err := NameAndTags(id.Bytes())
 	if err != nil {
 		return nil, false
 	}
 
-	it := id.iterFn(tagPairs)
+	it := id.iterPool.Get()
+	it.Reset(tagPairs)
 	defer it.Close()
 
 	for it.Next() {
@@ -127,52 +127,52 @@ func NameAndTags(id []byte) ([]byte, []byte, error) {
 }
 
 type sortedTagIterator struct {
-	tagPairs []byte
-	idx      int
-	tagName  []byte
-	tagValue []byte
-	err      error
-	pool     id.SortedTagIteratorPool
+	sortedTagPairs []byte
+	idx            int
+	tagName        []byte
+	tagValue       []byte
+	err            error
+	pool           id.SortedTagIteratorPool
 }
 
 // NewSortedTagIterator creates a new sorted tag iterator.
-func NewSortedTagIterator(tagPairs []byte) id.SortedTagIterator {
-	return NewPooledSortedTagIterator(tagPairs, nil)
+func NewSortedTagIterator(sortedTagPairs []byte) id.SortedTagIterator {
+	return NewPooledSortedTagIterator(sortedTagPairs, nil)
 }
 
 // NewPooledSortedTagIterator creates a new pooled sorted tag iterator.
-func NewPooledSortedTagIterator(tagPairs []byte, pool id.SortedTagIteratorPool) id.SortedTagIterator {
+func NewPooledSortedTagIterator(sortedTagPairs []byte, pool id.SortedTagIteratorPool) id.SortedTagIterator {
 	it := &sortedTagIterator{pool: pool}
-	it.Reset(tagPairs)
+	it.Reset(sortedTagPairs)
 	return it
 }
 
-func (it *sortedTagIterator) Reset(tagPairs []byte) {
-	it.tagPairs = tagPairs
+func (it *sortedTagIterator) Reset(sortedTagPairs []byte) {
+	it.sortedTagPairs = sortedTagPairs
 	it.idx = 0
 	it.tagName = nil
 	it.tagValue = nil
 	it.err = nil
 }
 
 func (it *sortedTagIterator) Next() bool {
-	if it.err != nil || it.idx >= len(it.tagPairs) {
+	if it.err != nil || it.idx >= len(it.sortedTagPairs) {
 		return false
 	}
-	nameSplitterIdx := bytes.IndexByte(it.tagPairs[it.idx:], tagNameSplitter)
+	nameSplitterIdx := bytes.IndexByte(it.sortedTagPairs[it.idx:], tagNameSplitter)
 	if nameSplitterIdx == -1 {
 		it.err = errInvalidM3Metric
 		return false
 	}
 	nameSplitterIdx = it.idx + nameSplitterIdx
-	pairSplitterIdx := bytes.IndexByte(it.tagPairs[nameSplitterIdx+1:], tagPairSplitter)
+	pairSplitterIdx := bytes.IndexByte(it.sortedTagPairs[nameSplitterIdx+1:], tagPairSplitter)
 	if pairSplitterIdx != -1 {
 		pairSplitterIdx = nameSplitterIdx + 1 + pairSplitterIdx
 	} else {
-		pairSplitterIdx = len(it.tagPairs)
+		pairSplitterIdx = len(it.sortedTagPairs)
 	}
-	it.tagName = it.tagPairs[it.idx:nameSplitterIdx]
-	it.tagValue = it.tagPairs[nameSplitterIdx+1 : pairSplitterIdx]
+	it.tagName = it.sortedTagPairs[it.idx:nameSplitterIdx]
+	it.tagValue = it.sortedTagPairs[nameSplitterIdx+1 : pairSplitterIdx]
 	it.idx = pairSplitterIdx
 	return true
 }
@@ -186,7 +186,7 @@ func (it *sortedTagIterator) Err() error {
 }
 
 func (it *sortedTagIterator) Close() {
-	it.tagPairs = nil
+	it.sortedTagPairs = nil
 	it.idx = 0
 	it.tagName = nil
 	it.tagValue = nil

metric/id/tag.go

@@ -45,11 +45,10 @@ func (tp TagPairsByNameAsc) Less(i, j int) bool {
 // SortedTagIteratorFn creates a new sorted tag iterator given id tag pairs.
 type SortedTagIteratorFn func(tagPairs []byte) SortedTagIterator
 
-// SortedTagIterator iterates over a set of tag names and values
-// sorted by tag names in ascending order.
+// SortedTagIterator iterates over a set of tag pairs sorted by tag names.
 type SortedTagIterator interface {
 	// Reset resets the iterator.
-	Reset(tagPairs []byte)
+	Reset(sortedTagPairs []byte)
 
 	// Next returns true if there are more tag names and values.
 	Next() bool

rules/ruleset.go

@@ -29,7 +29,7 @@ import (
 
 	"github.com/m3db/m3metrics/filters"
 	"github.com/m3db/m3metrics/generated/proto/schema"
-	mid "github.com/m3db/m3metrics/metric/id"
+	metricID "github.com/m3db/m3metrics/metric/id"
 	"github.com/m3db/m3metrics/policy"
 )
 
@@ -52,14 +52,14 @@ type activeRuleSet struct {
 	rollupRules     []*rollupRule
 	cutoverTimesAsc []int64
 	tagFilterOpts   filters.TagsFilterOptions
-	newRollupIDFn   mid.NewIDFn
+	newRollupIDFn   metricID.NewIDFn
 }
 
 func newActiveRuleSet(
 	mappingRules []*mappingRule,
 	rollupRules []*rollupRule,
 	tagFilterOpts filters.TagsFilterOptions,
-	newRollupIDFn mid.NewIDFn,
+	newRollupIDFn metricID.NewIDFn,
 ) *activeRuleSet {
 	uniqueCutoverTimes := make(map[int64]struct{})
 	for _, mappingRule := range mappingRules {
@@ -224,7 +224,7 @@ func (as *activeRuleSet) toRollupResults(id []byte, cutoverNanos int64, targets
 		return nil
 	}
 
-	var tagPairs []mid.TagPair
+	var tagPairs []metricID.TagPair
 	rollups := make([]RollupResult, 0, len(targets))
 	for _, target := range targets {
 		tagPairs = tagPairs[:0]
@@ -240,7 +240,7 @@ func (as *activeRuleSet) toRollupResults(id []byte, cutoverNanos int64, targets
 			tagName, tagVal := tagIter.Current()
 			res := bytes.Compare(tagName, target.Tags[targetTagIdx])
 			if res == 0 {
-				tagPairs = append(tagPairs, mid.TagPair{Name: tagName, Value: tagVal})
+				tagPairs = append(tagPairs, metricID.TagPair{Name: tagName, Value: tagVal})
 				targetTagIdx++
 				hasMoreTags = tagIter.Next()
 				continue
@@ -316,7 +316,7 @@ type ruleSet struct {
 	mappingRules       []*mappingRule
 	rollupRules        []*rollupRule
 	tagsFilterOpts     filters.TagsFilterOptions
-	newRollupIDFn      mid.NewIDFn
+	newRollupIDFn      metricID.NewIDFn
 }
 
 // NewRuleSet creates a new ruleset.

rules/ruleset_test.go

@@ -1714,7 +1714,7 @@ func testRollupRulesConfig() []*schema.RollupRule {
 
 func testTagsFilterOptions() filters.TagsFilterOptions {
 	return filters.TagsFilterOptions{
-		NameTagName:         []byte("name"),
+		NameTagKey:          []byte("name"),
 		NameAndTagsFn:       func(b []byte) ([]byte, []byte, error) { return nil, b, nil },
 		SortedTagIteratorFn: filters.NewMockSortedTagIterator,
 	}