dispatch/vendor/github.com/blevesearch/bleve/index_alias_impl.go
2016-03-01 01:51:26 +01:00

577 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 bleve
import (
"sort"
"sync"
"time"
"github.com/blevesearch/bleve/document"
"github.com/blevesearch/bleve/index"
"github.com/blevesearch/bleve/index/store"
"github.com/blevesearch/bleve/search"
)
type indexAliasImpl struct {
indexes []Index
mutex sync.RWMutex
open bool
}
// NewIndexAlias creates a new IndexAlias over the provided
// Index objects.
func NewIndexAlias(indexes ...Index) *indexAliasImpl {
return &indexAliasImpl{
indexes: indexes,
open: true,
}
}
func (i *indexAliasImpl) isAliasToSingleIndex() error {
if len(i.indexes) < 1 {
return ErrorAliasEmpty
} else if len(i.indexes) > 1 {
return ErrorAliasMulti
}
return nil
}
func (i *indexAliasImpl) Index(id string, data interface{}) error {
i.mutex.RLock()
defer i.mutex.RUnlock()
if !i.open {
return ErrorIndexClosed
}
err := i.isAliasToSingleIndex()
if err != nil {
return err
}
return i.indexes[0].Index(id, data)
}
func (i *indexAliasImpl) Delete(id string) error {
i.mutex.RLock()
defer i.mutex.RUnlock()
if !i.open {
return ErrorIndexClosed
}
err := i.isAliasToSingleIndex()
if err != nil {
return err
}
return i.indexes[0].Delete(id)
}
func (i *indexAliasImpl) Batch(b *Batch) error {
i.mutex.RLock()
defer i.mutex.RUnlock()
if !i.open {
return ErrorIndexClosed
}
err := i.isAliasToSingleIndex()
if err != nil {
return err
}
return i.indexes[0].Batch(b)
}
func (i *indexAliasImpl) Document(id string) (*document.Document, error) {
i.mutex.RLock()
defer i.mutex.RUnlock()
if !i.open {
return nil, ErrorIndexClosed
}
err := i.isAliasToSingleIndex()
if err != nil {
return nil, err
}
return i.indexes[0].Document(id)
}
func (i *indexAliasImpl) DocCount() (uint64, error) {
i.mutex.RLock()
defer i.mutex.RUnlock()
rv := uint64(0)
if !i.open {
return 0, ErrorIndexClosed
}
for _, index := range i.indexes {
otherCount, err := index.DocCount()
if err != nil {
return 0, err
}
rv += otherCount
}
return rv, nil
}
func (i *indexAliasImpl) Search(req *SearchRequest) (*SearchResult, error) {
i.mutex.RLock()
defer i.mutex.RUnlock()
if !i.open {
return nil, ErrorIndexClosed
}
if len(i.indexes) < 1 {
return nil, ErrorAliasEmpty
}
// short circuit the simple case
if len(i.indexes) == 1 {
return i.indexes[0].Search(req)
}
return MultiSearch(req, i.indexes...)
}
func (i *indexAliasImpl) Fields() ([]string, error) {
i.mutex.RLock()
defer i.mutex.RUnlock()
if !i.open {
return nil, ErrorIndexClosed
}
err := i.isAliasToSingleIndex()
if err != nil {
return nil, err
}
return i.indexes[0].Fields()
}
func (i *indexAliasImpl) FieldDict(field string) (index.FieldDict, error) {
i.mutex.RLock()
if !i.open {
i.mutex.RUnlock()
return nil, ErrorIndexClosed
}
err := i.isAliasToSingleIndex()
if err != nil {
i.mutex.RUnlock()
return nil, err
}
fieldDict, err := i.indexes[0].FieldDict(field)
if err != nil {
i.mutex.RUnlock()
return nil, err
}
return &indexAliasImplFieldDict{
index: i,
fieldDict: fieldDict,
}, nil
}
func (i *indexAliasImpl) FieldDictRange(field string, startTerm []byte, endTerm []byte) (index.FieldDict, error) {
i.mutex.RLock()
if !i.open {
i.mutex.RUnlock()
return nil, ErrorIndexClosed
}
err := i.isAliasToSingleIndex()
if err != nil {
i.mutex.RUnlock()
return nil, err
}
fieldDict, err := i.indexes[0].FieldDictRange(field, startTerm, endTerm)
if err != nil {
i.mutex.RUnlock()
return nil, err
}
return &indexAliasImplFieldDict{
index: i,
fieldDict: fieldDict,
}, nil
}
func (i *indexAliasImpl) FieldDictPrefix(field string, termPrefix []byte) (index.FieldDict, error) {
i.mutex.RLock()
if !i.open {
i.mutex.RUnlock()
return nil, ErrorIndexClosed
}
err := i.isAliasToSingleIndex()
if err != nil {
i.mutex.RUnlock()
return nil, err
}
fieldDict, err := i.indexes[0].FieldDictPrefix(field, termPrefix)
if err != nil {
i.mutex.RUnlock()
return nil, err
}
return &indexAliasImplFieldDict{
index: i,
fieldDict: fieldDict,
}, nil
}
func (i *indexAliasImpl) DumpAll() chan interface{} {
i.mutex.RLock()
defer i.mutex.RUnlock()
if !i.open {
return nil
}
err := i.isAliasToSingleIndex()
if err != nil {
return nil
}
return i.indexes[0].DumpAll()
}
func (i *indexAliasImpl) DumpDoc(id string) chan interface{} {
i.mutex.RLock()
defer i.mutex.RUnlock()
if !i.open {
return nil
}
err := i.isAliasToSingleIndex()
if err != nil {
return nil
}
return i.indexes[0].DumpDoc(id)
}
func (i *indexAliasImpl) DumpFields() chan interface{} {
i.mutex.RLock()
defer i.mutex.RUnlock()
if !i.open {
return nil
}
err := i.isAliasToSingleIndex()
if err != nil {
return nil
}
return i.indexes[0].DumpFields()
}
func (i *indexAliasImpl) Close() error {
i.mutex.Lock()
defer i.mutex.Unlock()
i.open = false
return nil
}
func (i *indexAliasImpl) Mapping() *IndexMapping {
i.mutex.RLock()
defer i.mutex.RUnlock()
if !i.open {
return nil
}
err := i.isAliasToSingleIndex()
if err != nil {
return nil
}
return i.indexes[0].Mapping()
}
func (i *indexAliasImpl) Stats() *IndexStat {
i.mutex.RLock()
defer i.mutex.RUnlock()
if !i.open {
return nil
}
err := i.isAliasToSingleIndex()
if err != nil {
return nil
}
return i.indexes[0].Stats()
}
func (i *indexAliasImpl) GetInternal(key []byte) ([]byte, error) {
i.mutex.RLock()
defer i.mutex.RUnlock()
if !i.open {
return nil, ErrorIndexClosed
}
err := i.isAliasToSingleIndex()
if err != nil {
return nil, err
}
return i.indexes[0].GetInternal(key)
}
func (i *indexAliasImpl) SetInternal(key, val []byte) error {
i.mutex.RLock()
defer i.mutex.RUnlock()
if !i.open {
return ErrorIndexClosed
}
err := i.isAliasToSingleIndex()
if err != nil {
return err
}
return i.indexes[0].SetInternal(key, val)
}
func (i *indexAliasImpl) DeleteInternal(key []byte) error {
i.mutex.RLock()
defer i.mutex.RUnlock()
if !i.open {
return ErrorIndexClosed
}
err := i.isAliasToSingleIndex()
if err != nil {
return err
}
return i.indexes[0].DeleteInternal(key)
}
func (i *indexAliasImpl) Advanced() (index.Index, store.KVStore, error) {
i.mutex.RLock()
defer i.mutex.RUnlock()
if !i.open {
return nil, nil, ErrorIndexClosed
}
err := i.isAliasToSingleIndex()
if err != nil {
return nil, nil, err
}
return i.indexes[0].Advanced()
}
func (i *indexAliasImpl) Add(indexes ...Index) {
i.mutex.Lock()
defer i.mutex.Unlock()
i.indexes = append(i.indexes, indexes...)
}
func (i *indexAliasImpl) removeSingle(index Index) {
for pos, in := range i.indexes {
if in == index {
i.indexes = append(i.indexes[:pos], i.indexes[pos+1:]...)
break
}
}
}
func (i *indexAliasImpl) Remove(indexes ...Index) {
i.mutex.Lock()
defer i.mutex.Unlock()
for _, in := range indexes {
i.removeSingle(in)
}
}
func (i *indexAliasImpl) Swap(in, out []Index) {
i.mutex.Lock()
defer i.mutex.Unlock()
// add
i.indexes = append(i.indexes, in...)
// delete
for _, ind := range out {
i.removeSingle(ind)
}
}
// createChildSearchRequest creates a separate
// request from the original
// For now, avoid data race on req structure.
// TODO disable highligh/field load on child
// requests, and add code to do this only on
// the actual final results.
// Perhaps that part needs to be optional,
// could be slower in remote usages.
func createChildSearchRequest(req *SearchRequest) *SearchRequest {
rv := SearchRequest{
Query: req.Query,
Size: req.Size + req.From,
From: 0,
Highlight: req.Highlight,
Fields: req.Fields,
Facets: req.Facets,
Explain: req.Explain,
}
return &rv
}
// MultiSearch executes a SearchRequest across multiple
// Index objects, then merges the results.
func MultiSearch(req *SearchRequest, indexes ...Index) (*SearchResult, error) {
searchStart := time.Now()
results := make(chan *SearchResult)
errs := make(chan error)
// run search on each index in separate go routine
var waitGroup sync.WaitGroup
var searchChildIndex = func(waitGroup *sync.WaitGroup, in Index, results chan *SearchResult, errs chan error) {
go func() {
defer waitGroup.Done()
childReq := createChildSearchRequest(req)
searchResult, err := in.Search(childReq)
if err != nil {
errs <- err
} else {
results <- searchResult
}
}()
}
for _, in := range indexes {
waitGroup.Add(1)
searchChildIndex(&waitGroup, in, results, errs)
}
// on another go routine, close after finished
go func() {
waitGroup.Wait()
close(results)
close(errs)
}()
var sr *SearchResult
var err error
var result *SearchResult
ok := true
for ok {
select {
case result, ok = <-results:
if ok {
if sr == nil {
// first result
sr = result
} else {
// merge with previous
sr.Merge(result)
}
}
case err, ok = <-errs:
// for now stop on any error
// FIXME offer other behaviors
if err != nil {
return nil, err
}
}
}
// merge just concatenated all the hits
// now lets clean it up
// first sort it by score
sort.Sort(sr.Hits)
// now skip over the correct From
if req.From > 0 && len(sr.Hits) > req.From {
sr.Hits = sr.Hits[req.From:]
} else if req.From > 0 {
sr.Hits = search.DocumentMatchCollection{}
}
// now trim to the correct size
if req.Size > 0 && len(sr.Hits) > req.Size {
sr.Hits = sr.Hits[0:req.Size]
}
// fix up facets
for name, fr := range req.Facets {
sr.Facets.Fixup(name, fr.Size)
}
// fix up original request
sr.Request = req
searchDuration := time.Since(searchStart)
sr.Took = searchDuration
return sr, nil
}
func (i *indexAliasImpl) NewBatch() *Batch {
i.mutex.RLock()
defer i.mutex.RUnlock()
if !i.open {
return nil
}
err := i.isAliasToSingleIndex()
if err != nil {
return nil
}
return i.indexes[0].NewBatch()
}
type indexAliasImplFieldDict struct {
index *indexAliasImpl
fieldDict index.FieldDict
}
func (f *indexAliasImplFieldDict) Next() (*index.DictEntry, error) {
return f.fieldDict.Next()
}
func (f *indexAliasImplFieldDict) Close() error {
defer f.index.mutex.RUnlock()
return f.fieldDict.Close()
}