mirror of
https://codeberg.org/forgejo/forgejo
synced 2024-08-25 17:11:16 +02:00
159 lines
4 KiB
Go
Vendored
159 lines
4 KiB
Go
Vendored
// Copyright (c) 2017 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 zap
|
|
|
|
import (
|
|
"fmt"
|
|
|
|
"github.com/RoaringBitmap/roaring"
|
|
index "github.com/blevesearch/bleve_index_api"
|
|
segment "github.com/blevesearch/scorch_segment_api/v2"
|
|
"github.com/blevesearch/vellum"
|
|
)
|
|
|
|
// Dictionary is the zap representation of the term dictionary
|
|
type Dictionary struct {
|
|
sb *SegmentBase
|
|
field string
|
|
fieldID uint16
|
|
fst *vellum.FST
|
|
fstReader *vellum.Reader
|
|
}
|
|
|
|
// represents an immutable, empty dictionary
|
|
var emptyDictionary = &Dictionary{}
|
|
|
|
// PostingsList returns the postings list for the specified term
|
|
func (d *Dictionary) PostingsList(term []byte, except *roaring.Bitmap,
|
|
prealloc segment.PostingsList) (segment.PostingsList, error) {
|
|
var preallocPL *PostingsList
|
|
pl, ok := prealloc.(*PostingsList)
|
|
if ok && pl != nil {
|
|
preallocPL = pl
|
|
}
|
|
return d.postingsList(term, except, preallocPL)
|
|
}
|
|
|
|
func (d *Dictionary) postingsList(term []byte, except *roaring.Bitmap, rv *PostingsList) (*PostingsList, error) {
|
|
if d.fstReader == nil {
|
|
if rv == nil || rv == emptyPostingsList {
|
|
return emptyPostingsList, nil
|
|
}
|
|
return d.postingsListInit(rv, except), nil
|
|
}
|
|
|
|
postingsOffset, exists, err := d.fstReader.Get(term)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("vellum err: %v", err)
|
|
}
|
|
if !exists {
|
|
if rv == nil || rv == emptyPostingsList {
|
|
return emptyPostingsList, nil
|
|
}
|
|
return d.postingsListInit(rv, except), nil
|
|
}
|
|
|
|
return d.postingsListFromOffset(postingsOffset, except, rv)
|
|
}
|
|
|
|
func (d *Dictionary) postingsListFromOffset(postingsOffset uint64, except *roaring.Bitmap, rv *PostingsList) (*PostingsList, error) {
|
|
rv = d.postingsListInit(rv, except)
|
|
|
|
err := rv.read(postingsOffset, d)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
return rv, nil
|
|
}
|
|
|
|
func (d *Dictionary) postingsListInit(rv *PostingsList, except *roaring.Bitmap) *PostingsList {
|
|
if rv == nil || rv == emptyPostingsList {
|
|
rv = &PostingsList{}
|
|
} else {
|
|
postings := rv.postings
|
|
if postings != nil {
|
|
postings.Clear()
|
|
}
|
|
|
|
*rv = PostingsList{} // clear the struct
|
|
|
|
rv.postings = postings
|
|
}
|
|
rv.sb = d.sb
|
|
rv.except = except
|
|
return rv
|
|
}
|
|
|
|
func (d *Dictionary) Contains(key []byte) (bool, error) {
|
|
if d.fst != nil {
|
|
return d.fst.Contains(key)
|
|
}
|
|
return false, nil
|
|
}
|
|
|
|
// AutomatonIterator returns an iterator which only visits terms
|
|
// having the the vellum automaton and start/end key range
|
|
func (d *Dictionary) AutomatonIterator(a segment.Automaton,
|
|
startKeyInclusive, endKeyExclusive []byte) segment.DictionaryIterator {
|
|
if d.fst != nil {
|
|
rv := &DictionaryIterator{
|
|
d: d,
|
|
}
|
|
|
|
itr, err := d.fst.Search(a, startKeyInclusive, endKeyExclusive)
|
|
if err == nil {
|
|
rv.itr = itr
|
|
} else if err != vellum.ErrIteratorDone {
|
|
rv.err = err
|
|
}
|
|
|
|
return rv
|
|
}
|
|
return emptyDictionaryIterator
|
|
}
|
|
|
|
// DictionaryIterator is an iterator for term dictionary
|
|
type DictionaryIterator struct {
|
|
d *Dictionary
|
|
itr vellum.Iterator
|
|
err error
|
|
tmp PostingsList
|
|
entry index.DictEntry
|
|
omitCount bool
|
|
}
|
|
|
|
var emptyDictionaryIterator = &DictionaryIterator{}
|
|
|
|
// Next returns the next entry in the dictionary
|
|
func (i *DictionaryIterator) Next() (*index.DictEntry, error) {
|
|
if i.err != nil && i.err != vellum.ErrIteratorDone {
|
|
return nil, i.err
|
|
} else if i.itr == nil || i.err == vellum.ErrIteratorDone {
|
|
return nil, nil
|
|
}
|
|
term, postingsOffset := i.itr.Current()
|
|
i.entry.Term = string(term)
|
|
if !i.omitCount {
|
|
i.err = i.tmp.read(postingsOffset, i.d)
|
|
if i.err != nil {
|
|
return nil, i.err
|
|
}
|
|
i.entry.Count = i.tmp.Count()
|
|
}
|
|
i.err = i.itr.Next()
|
|
return &i.entry, nil
|
|
}
|