gitea/vendor/github.com/blevesearch/bleve/search/searcher/search_disjunction.go
Lunny Xiao a380cfd8e0 Update bleve dependency to latest master revision (#6100)
* update bleve to master b17287a86f6cac923a5d886e10618df994eeb54b6724eac2e3b8dde89cfbe3a2

* remove unused pkg from dep file

* change bleve from master to recent revision
2019-02-17 19:50:26 -05:00

109 lines
3.3 KiB
Go
Vendored

// Copyright (c) 2018 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 (
"fmt"
"github.com/blevesearch/bleve/index"
"github.com/blevesearch/bleve/search"
)
// DisjunctionMaxClauseCount is a compile time setting that applications can
// adjust to non-zero value to cause the DisjunctionSearcher to return an
// error instead of exeucting searches when the size exceeds this value.
var DisjunctionMaxClauseCount = 0
// DisjunctionHeapTakeover is a compile time setting that applications can
// adjust to control when the DisjunctionSearcher will switch from a simple
// slice implementation to a heap implementation.
var DisjunctionHeapTakeover = 10
func NewDisjunctionSearcher(indexReader index.IndexReader,
qsearchers []search.Searcher, min float64, options search.SearcherOptions) (
search.Searcher, error) {
return newDisjunctionSearcher(indexReader, qsearchers, min, options, true)
}
func newDisjunctionSearcher(indexReader index.IndexReader,
qsearchers []search.Searcher, min float64, options search.SearcherOptions,
limit bool) (search.Searcher, error) {
// attempt the "unadorned" disjunction optimization only when we
// do not need extra information like freq-norm's or term vectors
// and the requested min is simple
if len(qsearchers) > 1 && min <= 1 &&
options.Score == "none" && !options.IncludeTermVectors {
rv, err := optimizeCompositeSearcher("disjunction:unadorned",
indexReader, qsearchers, options)
if err != nil || rv != nil {
return rv, err
}
}
if len(qsearchers) > DisjunctionHeapTakeover {
return newDisjunctionHeapSearcher(indexReader, qsearchers, min, options,
limit)
}
return newDisjunctionSliceSearcher(indexReader, qsearchers, min, options,
limit)
}
func optimizeCompositeSearcher(optimizationKind string,
indexReader index.IndexReader, qsearchers []search.Searcher,
options search.SearcherOptions) (search.Searcher, error) {
var octx index.OptimizableContext
for _, searcher := range qsearchers {
o, ok := searcher.(index.Optimizable)
if !ok {
return nil, nil
}
var err error
octx, err = o.Optimize(optimizationKind, octx)
if err != nil {
return nil, err
}
if octx == nil {
return nil, nil
}
}
optimized, err := octx.Finish()
if err != nil || optimized == nil {
return nil, err
}
tfr, ok := optimized.(index.TermFieldReader)
if !ok {
return nil, nil
}
return newTermSearcherFromReader(indexReader, tfr,
[]byte(optimizationKind), "*", 1.0, options)
}
func tooManyClauses(count int) bool {
if DisjunctionMaxClauseCount != 0 && count > DisjunctionMaxClauseCount {
return true
}
return false
}
func tooManyClausesErr(count int) error {
return fmt.Errorf("TooManyClauses[%d > maxClauseCount, which is set to %d]",
count, DisjunctionMaxClauseCount)
}