Make facets much faster

index/index.go

@@ -77,8 +77,10 @@ type IndexReader interface {
 
 	Document(id string) (*document.Document, error)
 	DocumentFieldTerms(id string) (FieldTerms, error)
+	DocumentFieldTermsForFields(id string, fieldIDs []uint16, fields []string) (FieldTerms, error)
 
 	Fields() ([]string, error)
+	FieldIDs(fields []string) ([]uint16, error)
 
 	GetInternal(key []byte) ([]byte, error)
 

index/upside_down/index_reader.go

@@ -13,6 +13,7 @@ import (
 	"github.com/blevesearch/bleve/document"
 	"github.com/blevesearch/bleve/index"
 	"github.com/blevesearch/bleve/index/store"
+	"fmt"
 )
 
 type IndexReader struct {
@@ -110,6 +111,27 @@ func (i *IndexReader) DocumentFieldTerms(id string) (index.FieldTerms, error) {
 	return rv, nil
 }
 
+func (i *IndexReader) DocumentFieldTermsForFields(id string, fieldIDs []uint16, fields []string) (index.FieldTerms, error) {
+	back, err := i.index.backIndexRowForDoc(i.kvreader, id)
+	if err != nil {
+		return nil, err
+	}
+	rv := make(index.FieldTerms, len(fieldIDs))
+	for _, entry := range back.termEntries {
+		for id, field := range fieldIDs {
+			if field == uint16(*entry.Field) {
+				terms, ok := rv[fields[id]]
+				if !ok {
+					terms = make([]string, 0)
+				}
+				terms = append(terms, *entry.Term)
+				rv[fields[id]] = terms
+			}
+		}
+	}
+	return rv, nil
+}
+
 func (i *IndexReader) Fields() (fields []string, err error) {
 	fields = make([]string, 0)
 	it := i.kvreader.PrefixIterator([]byte{'f'})
@@ -139,6 +161,17 @@ func (i *IndexReader) Fields() (fields []string, err error) {
 	return
 }
 
+func (i *IndexReader) FieldIDs(fields []string) (ids []uint16, err error) {
+	for _, f := range fields {
+		id, found := i.index.fieldCache.FieldNamed(f, false)
+		if !found {
+			return nil, fmt.Errorf("Field %s was not found in cache", f)
+		}
+		ids = append(ids, id)
+	}
+	return
+}
+
 func (i *IndexReader) GetInternal(key []byte) ([]byte, error) {
 	internalRow := NewInternalRow(key, nil)
 	return i.kvreader.Get(internalRow.Key())

search.go

@@ -191,6 +191,8 @@ func (h *HighlightRequest) AddField(field string) {
 // Facets describe the set of facets to be computed.
 // Explain triggers inclusion of additional search
 // result score explanations.
+// Sort specifies the sorting for the returned results
+// results will be sorted by score if this is empty
 //
 // A special field named "*" can be used to return all fields.
 type SearchRequest struct {
@@ -201,6 +203,7 @@ type SearchRequest struct {
 	Fields    []string          `json:"fields"`
 	Facets    FacetsRequest     `json:"facets"`
 	Explain   bool              `json:"explain"`
+	Sort      map[string]bool   `json:"sort"`
 }
 
 func (sr *SearchRequest) Validate() error {
@@ -220,6 +223,14 @@ func (r *SearchRequest) AddFacet(facetName string, f *FacetRequest) {
 	r.Facets[facetName] = f
 }
 
+// AddSort field in ascending or descending direction
+func (r *SearchRequest) AddSort(field string, ascending bool) {
+	if r.Sort == nil {
+		r.Sort = make(map[string]bool)
+	}
+	r.Sort[field] = ascending
+}
+
 // UnmarshalJSON deserializes a JSON representation of
 // a SearchRequest
 func (r *SearchRequest) UnmarshalJSON(input []byte) error {
@@ -231,6 +242,7 @@ func (r *SearchRequest) UnmarshalJSON(input []byte) error {
 		Fields    []string          `json:"fields"`
 		Facets    FacetsRequest     `json:"facets"`
 		Explain   bool              `json:"explain"`
+		Sort      map[string]bool   `json:"sort"`
 	}
 
 	err := json.Unmarshal(input, &temp)
@@ -248,6 +260,7 @@ func (r *SearchRequest) UnmarshalJSON(input []byte) error {
 	r.Highlight = temp.Highlight
 	r.Fields = temp.Fields
 	r.Facets = temp.Facets
+	r.Sort = temp.Sort
 	r.Query, err = ParseQuery(temp.Q)
 	if err != nil {
 		return err
@@ -280,6 +293,7 @@ func NewSearchRequestOptions(q Query, size, from int, explain bool) *SearchReque
 		Size:    size,
 		From:    from,
 		Explain: explain,
+		Sort:    make(map[string]bool),
 	}
 }
 
@@ -307,7 +321,7 @@ func (iem IndexErrMap) UnmarshalJSON(data []byte) error {
 	return nil
 }
 
-// SearchStatus is a secion in the SearchResult reporting how many
+// SearchStatus is a section in the SearchResult reporting how many
 // underlying indexes were queried, how many were successful/failed
 // and a map of any errors that were encountered
 type SearchStatus struct {

search/facets/facet_builder_datetime.go

@@ -49,6 +49,10 @@ func (fb *DateTimeFacetBuilder) AddRange(name string, start, end time.Time) {
 	fb.ranges[name] = &r
 }
 
+func (fb *DateTimeFacetBuilder) Field() string {
+	return fb.field
+}
+
 func (fb *DateTimeFacetBuilder) Update(ft index.FieldTerms) {
 	terms, ok := ft[fb.field]
 	if ok {

search/facets/facet_builder_numeric.go

@@ -48,6 +48,10 @@ func (fb *NumericFacetBuilder) AddRange(name string, min, max *float64) {
 	fb.ranges[name] = &r
 }
 
+func (fb *NumericFacetBuilder) Field() string {
+	return fb.field
+}
+
 func (fb *NumericFacetBuilder) Update(ft index.FieldTerms) {
 	terms, ok := ft[fb.field]
 	if ok {

search/facets/facet_builder_terms.go

@@ -32,6 +32,10 @@ func NewTermsFacetBuilder(field string, size int) *TermsFacetBuilder {
 	}
 }
 
+func (fb *TermsFacetBuilder) Field() string {
+	return fb.field
+}
+
 func (fb *TermsFacetBuilder) Update(ft index.FieldTerms) {
 	terms, ok := ft[fb.field]
 	if ok {

search/facets_builder.go

@@ -18,6 +18,7 @@ import (
 type FacetBuilder interface {
 	Update(index.FieldTerms)
 	Result() *FacetResult
+	Field() string
 }
 
 type FacetsBuilder struct {
@@ -37,7 +38,15 @@ func (fb *FacetsBuilder) Add(name string, facetBuilder FacetBuilder) {
 }
 
 func (fb *FacetsBuilder) Update(docMatch *DocumentMatch) error {
-	fieldTerms, err := fb.indexReader.DocumentFieldTerms(docMatch.ID)
+	var fields []string
+	for _, facetBuilder := range fb.facets {
+		fields = append(fields, facetBuilder.Field())
+	}
+	fieldIds, err := fb.indexReader.FieldIDs(fields)
+	if err != nil {
+		return err
+	}
+	fieldTerms, err := fb.indexReader.DocumentFieldTermsForFields(docMatch.ID, fieldIds, fields)
 	if err != nil {
 		return err
 	}