cpolis/cmd/backend/index.go

137 lines
2.7 KiB
Go

package backend
import (
"fmt"
"sync"
"github.com/blevesearch/bleve"
)
type (
Index struct {
index bleve.Index
mu sync.RWMutex
}
Result struct{ *bleve.SearchResult }
)
func (i *Index) isIndexed(filename string, errChan chan<- error) bool {
i.mu.RLock()
defer i.mu.RUnlock()
query := bleve.NewDocIDQuery([]string{filename})
request := bleve.NewSearchRequest(query)
result, err := i.index.Search(request)
if err != nil {
errChan <- fmt.Errorf("error searching for file %v in index: %v", filename, err)
return false
}
return len(result.Hits) > 0
}
func (i *Index) indexAllArticles(c *Config, db *DB) error {
articles, err := db.GetAllArticles()
if err != nil {
return fmt.Errorf("error getting all articles from DB: %v", err)
}
var wg sync.WaitGroup
errChan := make(chan error, len(articles))
go func() {
wg.Wait()
close(errChan)
}()
for _, article := range articles {
wg.Add(1)
go func() {
defer wg.Done()
filename := article.UUID.String()
content, err := article.ReadContent(c)
if err != nil {
errChan <- fmt.Errorf("error reading content of article %v: %v", filename, err)
return
}
if !i.isIndexed(filename, errChan) {
if err := i.Add(filename, content); err != nil {
errChan <- fmt.Errorf("error adding file %v to index: %v", filename, err)
return
}
}
errChan <- nil
}()
}
if err = <-errChan; err != nil {
return fmt.Errorf("error(s) indexing all articles: %v", err)
}
return nil
}
func InitIndex(c *Config) (*Index, error) {
var err error
index := new(Index)
index.index, err = bleve.Open(c.IndexDir)
if err != nil {
mapping := bleve.NewIndexMapping()
index.index, err = bleve.New(c.IndexDir, mapping)
if err != nil {
return nil, fmt.Errorf("error creating new index file: %v", err)
}
}
return index, err
}
func (i *Index) Add(filename, content string) error {
i.mu.Lock()
defer i.mu.Unlock()
doc := map[string]string{
"name": filename,
"body": content,
}
if err := i.index.Index(filename, doc); err != nil {
return fmt.Errorf("error indexing file %v: %v", filename, err)
}
return nil
}
func (i *Index) Query(q string) (*Result, error) {
i.mu.RLock()
defer i.mu.RUnlock()
query := bleve.NewQueryStringQuery(q)
request := bleve.NewSearchRequest(query)
result, err := i.index.Search(request)
if err != nil {
return nil, fmt.Errorf("error querying index for \"%v\": %v", q, err)
}
if len(result.Hits) < 1 {
return nil, nil
}
return &Result{result}, err
}
func (i *Index) Delete(filename string) error {
i.mu.Lock()
defer i.mu.Unlock()
if err := i.index.Delete(filename); err != nil {
return fmt.Errorf("error deleting file %v from index: %v", filename, err)
}
return nil
}