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bleve/analysis/analyzers/custom_analyzer/custom_analyzer.go
2015-08-11 21:22:03 +00:00

131 lines
3.6 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 custom_analyzer
import (
"fmt"
"github.com/blevesearch/bleve/analysis"
"github.com/blevesearch/bleve/registry"
)
const Name = "custom"
func AnalyzerConstructor(config map[string]interface{}, cache *registry.Cache) (*analysis.Analyzer, error) {
var err error
var charFilters []analysis.CharFilter
charFiltersNames, ok := config["char_filters"].([]string)
if ok {
charFilters, err = getCharFilters(charFiltersNames, cache)
if err != nil {
return nil, err
}
} else {
charFiltersNamesInterfaceSlice, ok := config["char_filters"].([]interface{})
if ok {
charFiltersNames, err := convertInterfaceSliceToStringSlice(charFiltersNamesInterfaceSlice, "char filter")
if err != nil {
return nil, err
}
charFilters, err = getCharFilters(charFiltersNames, cache)
if err != nil {
return nil, err
}
}
}
tokenizerName, ok := config["tokenizer"].(string)
if !ok {
return nil, fmt.Errorf("must specify tokenizer")
}
tokenizer, err := cache.TokenizerNamed(tokenizerName)
if err != nil {
return nil, err
}
var tokenFilters []analysis.TokenFilter
tokenFiltersNames, ok := config["token_filters"].([]string)
if ok {
tokenFilters, err = getTokenFilters(tokenFiltersNames, cache)
if err != nil {
return nil, err
}
} else {
tokenFiltersNamesInterfaceSlice, ok := config["token_filters"].([]interface{})
if ok {
tokenFiltersNames, err := convertInterfaceSliceToStringSlice(tokenFiltersNamesInterfaceSlice, "token filter")
if err != nil {
return nil, err
}
tokenFilters, err = getTokenFilters(tokenFiltersNames, cache)
if err != nil {
return nil, err
}
}
}
rv := analysis.Analyzer{
Tokenizer: tokenizer,
}
if charFilters != nil {
rv.CharFilters = charFilters
}
if tokenFilters != nil {
rv.TokenFilters = tokenFilters
}
return &rv, nil
}
func init() {
registry.RegisterAnalyzer(Name, AnalyzerConstructor)
}
func getCharFilters(charFilterNames []string, cache *registry.Cache) ([]analysis.CharFilter, error) {
charFilters := make([]analysis.CharFilter, len(charFilterNames))
for i, charFilterName := range charFilterNames {
charFilter, err := cache.CharFilterNamed(charFilterName)
if err != nil {
return nil, err
}
charFilters[i] = charFilter
}
return charFilters, nil
}
func getTokenFilters(tokenFilterNames []string, cache *registry.Cache) ([]analysis.TokenFilter, error) {
tokenFilters := make([]analysis.TokenFilter, len(tokenFilterNames))
for i, tokenFilterName := range tokenFilterNames {
tokenFilter, err := cache.TokenFilterNamed(tokenFilterName)
if err != nil {
return nil, err
}
tokenFilters[i] = tokenFilter
}
return tokenFilters, nil
}
func convertInterfaceSliceToStringSlice(interfaceSlice []interface{}, objType string) ([]string, error) {
stringSlice := make([]string, len(interfaceSlice))
for i, interfaceObj := range interfaceSlice {
stringObj, ok := interfaceObj.(string)
if ok {
stringSlice[i] = stringObj
} else {
return nil, fmt.Errorf(objType + " name must be a string")
}
}
return stringSlice, nil
}