60 lines
1.5 KiB
Go
60 lines
1.5 KiB
Go
// Copyright (c) 2014 Couchbase, Inc.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package truncate
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import (
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"fmt"
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"unicode/utf8"
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"github.com/blevesearch/bleve/analysis"
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"github.com/blevesearch/bleve/registry"
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)
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const Name = "truncate_token"
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type TruncateTokenFilter struct {
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length int
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}
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func NewTruncateTokenFilter(length int) *TruncateTokenFilter {
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return &TruncateTokenFilter{
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length: length,
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}
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}
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func (s *TruncateTokenFilter) Filter(input analysis.TokenStream) analysis.TokenStream {
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for _, token := range input {
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wordLen := utf8.RuneCount(token.Term)
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if wordLen > s.length {
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token.Term = analysis.TruncateRunes(token.Term, wordLen-s.length)
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}
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}
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return input
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}
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func TruncateTokenFilterConstructor(config map[string]interface{}, cache *registry.Cache) (analysis.TokenFilter, error) {
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lenVal, ok := config["length"].(float64)
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if !ok {
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return nil, fmt.Errorf("must specify length")
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}
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length := int(lenVal)
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return NewTruncateTokenFilter(length), nil
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}
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func init() {
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registry.RegisterTokenFilter(Name, TruncateTokenFilterConstructor)
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}
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