gitea/vendor/github.com/blevesearch/bleve/search/searcher/search_boolean.go
2019-11-27 11:23:33 +02:00

450 lines
10 KiB
Go

// Copyright (c) 2014 Couchbase, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package searcher
import (
"math"
"reflect"
"github.com/blevesearch/bleve/index"
"github.com/blevesearch/bleve/search"
"github.com/blevesearch/bleve/search/scorer"
"github.com/blevesearch/bleve/size"
)
var reflectStaticSizeBooleanSearcher int
func init() {
var bs BooleanSearcher
reflectStaticSizeBooleanSearcher = int(reflect.TypeOf(bs).Size())
}
type BooleanSearcher struct {
indexReader index.IndexReader
mustSearcher search.Searcher
shouldSearcher search.Searcher
mustNotSearcher search.Searcher
queryNorm float64
currMust *search.DocumentMatch
currShould *search.DocumentMatch
currMustNot *search.DocumentMatch
currentID index.IndexInternalID
min uint64
scorer *scorer.ConjunctionQueryScorer
matches []*search.DocumentMatch
initialized bool
done bool
}
func NewBooleanSearcher(indexReader index.IndexReader, mustSearcher search.Searcher, shouldSearcher search.Searcher, mustNotSearcher search.Searcher, options search.SearcherOptions) (*BooleanSearcher, error) {
// build our searcher
rv := BooleanSearcher{
indexReader: indexReader,
mustSearcher: mustSearcher,
shouldSearcher: shouldSearcher,
mustNotSearcher: mustNotSearcher,
scorer: scorer.NewConjunctionQueryScorer(options),
matches: make([]*search.DocumentMatch, 2),
}
rv.computeQueryNorm()
return &rv, nil
}
func (s *BooleanSearcher) Size() int {
sizeInBytes := reflectStaticSizeBooleanSearcher + size.SizeOfPtr
if s.mustSearcher != nil {
sizeInBytes += s.mustSearcher.Size()
}
if s.shouldSearcher != nil {
sizeInBytes += s.shouldSearcher.Size()
}
if s.mustNotSearcher != nil {
sizeInBytes += s.mustNotSearcher.Size()
}
sizeInBytes += s.scorer.Size()
for _, entry := range s.matches {
if entry != nil {
sizeInBytes += entry.Size()
}
}
return sizeInBytes
}
func (s *BooleanSearcher) computeQueryNorm() {
// first calculate sum of squared weights
sumOfSquaredWeights := 0.0
if s.mustSearcher != nil {
sumOfSquaredWeights += s.mustSearcher.Weight()
}
if s.shouldSearcher != nil {
sumOfSquaredWeights += s.shouldSearcher.Weight()
}
// now compute query norm from this
s.queryNorm = 1.0 / math.Sqrt(sumOfSquaredWeights)
// finally tell all the downstream searchers the norm
if s.mustSearcher != nil {
s.mustSearcher.SetQueryNorm(s.queryNorm)
}
if s.shouldSearcher != nil {
s.shouldSearcher.SetQueryNorm(s.queryNorm)
}
}
func (s *BooleanSearcher) initSearchers(ctx *search.SearchContext) error {
var err error
// get all searchers pointing at their first match
if s.mustSearcher != nil {
if s.currMust != nil {
ctx.DocumentMatchPool.Put(s.currMust)
}
s.currMust, err = s.mustSearcher.Next(ctx)
if err != nil {
return err
}
}
if s.shouldSearcher != nil {
if s.currShould != nil {
ctx.DocumentMatchPool.Put(s.currShould)
}
s.currShould, err = s.shouldSearcher.Next(ctx)
if err != nil {
return err
}
}
if s.mustNotSearcher != nil {
if s.currMustNot != nil {
ctx.DocumentMatchPool.Put(s.currMustNot)
}
s.currMustNot, err = s.mustNotSearcher.Next(ctx)
if err != nil {
return err
}
}
if s.mustSearcher != nil && s.currMust != nil {
s.currentID = s.currMust.IndexInternalID
} else if s.mustSearcher == nil && s.currShould != nil {
s.currentID = s.currShould.IndexInternalID
} else {
s.currentID = nil
}
s.initialized = true
return nil
}
func (s *BooleanSearcher) advanceNextMust(ctx *search.SearchContext, skipReturn *search.DocumentMatch) error {
var err error
if s.mustSearcher != nil {
if s.currMust != skipReturn {
ctx.DocumentMatchPool.Put(s.currMust)
}
s.currMust, err = s.mustSearcher.Next(ctx)
if err != nil {
return err
}
} else {
if s.currShould != skipReturn {
ctx.DocumentMatchPool.Put(s.currShould)
}
s.currShould, err = s.shouldSearcher.Next(ctx)
if err != nil {
return err
}
}
if s.mustSearcher != nil && s.currMust != nil {
s.currentID = s.currMust.IndexInternalID
} else if s.mustSearcher == nil && s.currShould != nil {
s.currentID = s.currShould.IndexInternalID
} else {
s.currentID = nil
}
return nil
}
func (s *BooleanSearcher) Weight() float64 {
var rv float64
if s.mustSearcher != nil {
rv += s.mustSearcher.Weight()
}
if s.shouldSearcher != nil {
rv += s.shouldSearcher.Weight()
}
return rv
}
func (s *BooleanSearcher) SetQueryNorm(qnorm float64) {
if s.mustSearcher != nil {
s.mustSearcher.SetQueryNorm(qnorm)
}
if s.shouldSearcher != nil {
s.shouldSearcher.SetQueryNorm(qnorm)
}
}
func (s *BooleanSearcher) Next(ctx *search.SearchContext) (*search.DocumentMatch, error) {
if s.done {
return nil, nil
}
if !s.initialized {
err := s.initSearchers(ctx)
if err != nil {
return nil, err
}
}
var err error
var rv *search.DocumentMatch
for s.currentID != nil {
if s.currMustNot != nil {
cmp := s.currMustNot.IndexInternalID.Compare(s.currentID)
if cmp < 0 {
ctx.DocumentMatchPool.Put(s.currMustNot)
// advance must not searcher to our candidate entry
s.currMustNot, err = s.mustNotSearcher.Advance(ctx, s.currentID)
if err != nil {
return nil, err
}
if s.currMustNot != nil && s.currMustNot.IndexInternalID.Equals(s.currentID) {
// the candidate is excluded
err = s.advanceNextMust(ctx, nil)
if err != nil {
return nil, err
}
continue
}
} else if cmp == 0 {
// the candidate is excluded
err = s.advanceNextMust(ctx, nil)
if err != nil {
return nil, err
}
continue
}
}
shouldCmpOrNil := 1 // NOTE: shouldCmp will also be 1 when currShould == nil.
if s.currShould != nil {
shouldCmpOrNil = s.currShould.IndexInternalID.Compare(s.currentID)
}
if shouldCmpOrNil < 0 {
ctx.DocumentMatchPool.Put(s.currShould)
// advance should searcher to our candidate entry
s.currShould, err = s.shouldSearcher.Advance(ctx, s.currentID)
if err != nil {
return nil, err
}
if s.currShould != nil && s.currShould.IndexInternalID.Equals(s.currentID) {
// score bonus matches should
var cons []*search.DocumentMatch
if s.currMust != nil {
cons = s.matches
cons[0] = s.currMust
cons[1] = s.currShould
} else {
cons = s.matches[0:1]
cons[0] = s.currShould
}
rv = s.scorer.Score(ctx, cons)
err = s.advanceNextMust(ctx, rv)
if err != nil {
return nil, err
}
break
} else if s.shouldSearcher.Min() == 0 {
// match is OK anyway
cons := s.matches[0:1]
cons[0] = s.currMust
rv = s.scorer.Score(ctx, cons)
err = s.advanceNextMust(ctx, rv)
if err != nil {
return nil, err
}
break
}
} else if shouldCmpOrNil == 0 {
// score bonus matches should
var cons []*search.DocumentMatch
if s.currMust != nil {
cons = s.matches
cons[0] = s.currMust
cons[1] = s.currShould
} else {
cons = s.matches[0:1]
cons[0] = s.currShould
}
rv = s.scorer.Score(ctx, cons)
err = s.advanceNextMust(ctx, rv)
if err != nil {
return nil, err
}
break
} else if s.shouldSearcher == nil || s.shouldSearcher.Min() == 0 {
// match is OK anyway
cons := s.matches[0:1]
cons[0] = s.currMust
rv = s.scorer.Score(ctx, cons)
err = s.advanceNextMust(ctx, rv)
if err != nil {
return nil, err
}
break
}
err = s.advanceNextMust(ctx, nil)
if err != nil {
return nil, err
}
}
if rv == nil {
s.done = true
}
return rv, nil
}
func (s *BooleanSearcher) Advance(ctx *search.SearchContext, ID index.IndexInternalID) (*search.DocumentMatch, error) {
if s.done {
return nil, nil
}
if !s.initialized {
err := s.initSearchers(ctx)
if err != nil {
return nil, err
}
}
// Advance the searcher only if the cursor is trailing the lookup ID
if s.currentID == nil || s.currentID.Compare(ID) < 0 {
var err error
if s.mustSearcher != nil {
if s.currMust != nil {
ctx.DocumentMatchPool.Put(s.currMust)
}
s.currMust, err = s.mustSearcher.Advance(ctx, ID)
if err != nil {
return nil, err
}
}
if s.shouldSearcher != nil {
if s.currShould != nil {
ctx.DocumentMatchPool.Put(s.currShould)
}
s.currShould, err = s.shouldSearcher.Advance(ctx, ID)
if err != nil {
return nil, err
}
}
if s.mustNotSearcher != nil {
// Additional check for mustNotSearcher, whose cursor isn't tracked by
// currentID to prevent it from moving when the searcher's tracked
// position is already ahead of or at the requested ID.
if s.currMustNot == nil || s.currMustNot.IndexInternalID.Compare(ID) < 0 {
if s.currMustNot != nil {
ctx.DocumentMatchPool.Put(s.currMustNot)
}
s.currMustNot, err = s.mustNotSearcher.Advance(ctx, ID)
if err != nil {
return nil, err
}
}
}
if s.mustSearcher != nil && s.currMust != nil {
s.currentID = s.currMust.IndexInternalID
} else if s.mustSearcher == nil && s.currShould != nil {
s.currentID = s.currShould.IndexInternalID
} else {
s.currentID = nil
}
}
return s.Next(ctx)
}
func (s *BooleanSearcher) Count() uint64 {
// for now return a worst case
var sum uint64
if s.mustSearcher != nil {
sum += s.mustSearcher.Count()
}
if s.shouldSearcher != nil {
sum += s.shouldSearcher.Count()
}
return sum
}
func (s *BooleanSearcher) Close() error {
var err0, err1, err2 error
if s.mustSearcher != nil {
err0 = s.mustSearcher.Close()
}
if s.shouldSearcher != nil {
err1 = s.shouldSearcher.Close()
}
if s.mustNotSearcher != nil {
err2 = s.mustNotSearcher.Close()
}
if err0 != nil {
return err0
}
if err1 != nil {
return err1
}
if err2 != nil {
return err2
}
return nil
}
func (s *BooleanSearcher) Min() int {
return 0
}
func (s *BooleanSearcher) DocumentMatchPoolSize() int {
rv := 3
if s.mustSearcher != nil {
rv += s.mustSearcher.DocumentMatchPoolSize()
}
if s.shouldSearcher != nil {
rv += s.shouldSearcher.DocumentMatchPoolSize()
}
if s.mustNotSearcher != nil {
rv += s.mustNotSearcher.DocumentMatchPoolSize()
}
return rv
}