8debf26cb7
many of these defaults were arbitrary, and not having defaults lets us more easily flag them for configuration added a shingle filter introduce new toke type for shingles
84 lines
2.0 KiB
Go
84 lines
2.0 KiB
Go
// Copyright (c) 2014 Couchbase, Inc.
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// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
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// except in compliance with the License. You may obtain a copy of the License at
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// http://www.apache.org/licenses/LICENSE-2.0
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// Unless required by applicable law or agreed to in writing, software distributed under the
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// License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
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// either express or implied. See the License for the specific language governing permissions
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// and limitations under the License.
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package analysis
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import (
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"fmt"
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"time"
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)
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type CharFilter interface {
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Filter([]byte) []byte
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}
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type TokenType int
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const (
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AlphaNumeric TokenType = iota
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Ideographic
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Numeric
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DateTime
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Shingle
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)
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type Token struct {
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Start int `json:"start"`
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End int `json:"end"`
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Term []byte `json:"term"`
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Position int `json:"position"`
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Type TokenType `json:"type"`
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KeyWord bool `json:"keyword"`
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}
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func (t *Token) String() string {
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return fmt.Sprintf("Start: %d End: %d Position: %d Token: %s Type: %d", t.Start, t.End, t.Position, string(t.Term), t.Type)
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}
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type TokenStream []*Token
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type Tokenizer interface {
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Tokenize([]byte) TokenStream
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}
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type TokenFilter interface {
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Filter(TokenStream) TokenStream
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}
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type Analyzer struct {
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CharFilters []CharFilter
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Tokenizer Tokenizer
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TokenFilters []TokenFilter
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}
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func (a *Analyzer) Analyze(input []byte) TokenStream {
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if a.CharFilters != nil {
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for _, cf := range a.CharFilters {
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input = cf.Filter(input)
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}
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}
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tokens := a.Tokenizer.Tokenize(input)
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if a.TokenFilters != nil {
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for _, tf := range a.TokenFilters {
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tokens = tf.Filter(tokens)
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}
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}
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return tokens
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}
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var ErrInvalidDateTime = fmt.Errorf("unable to parse datetime with any of the layouts")
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type DateTimeParser interface {
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ParseDateTime(string) (time.Time, error)
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}
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type ByteArrayConverter interface {
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Convert([]byte) (interface{}, error)
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}
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