Files
gonic/scanner/scanner.go
2019-05-23 13:48:16 +01:00

283 lines
7.0 KiB
Go

package scanner
// this scanner tries to scan with a single unsorted walk of the music
// directory - which means you can come across the cover of an album/folder
// before the tracks (and therefore the album) which is an issue because
// when inserting into the album table, we need a reference to the cover.
// to solve this we're using godirwalk's PostChildrenCallback and some globals
//
// Album -> needs a CoverID
// -> needs a FolderID (American Football)
// Folder -> needs a CoverID
// -> needs a ParentID
// Track -> needs an AlbumID
// -> needs a FolderID
import (
"fmt"
"io/ioutil"
"log"
"os"
"path"
"sync/atomic"
"time"
"github.com/jinzhu/gorm"
"github.com/karrick/godirwalk"
"github.com/pkg/errors"
"github.com/sentriz/gonic/model"
)
var (
IsScanning int32
)
type Scanner struct {
db *gorm.DB
tx *gorm.DB
musicPath string
seenPaths map[string]bool
folderCount uint
curFolders folderStack
curTracks []*model.Track
curCover *model.Cover
curAlbum *model.Album
curAArtist *model.AlbumArtist
}
func New(db *gorm.DB, musicPath string) *Scanner {
return &Scanner{
db: db,
musicPath: musicPath,
seenPaths: make(map[string]bool),
curFolders: make(folderStack, 0),
}
}
func (s *Scanner) handleCover(fullPath string, stat os.FileInfo) error {
s.curCover = &model.Cover{}
err := s.tx.Where("path = ?", fullPath).First(s.curCover).Error
if !gorm.IsRecordNotFoundError(err) &&
stat.ModTime().Before(s.curCover.UpdatedAt) {
// we found the record but it hasn't changed
return nil
}
s.curCover.Path = fullPath
image, err := ioutil.ReadFile(fullPath)
if err != nil {
return errors.Wrap(err, "reading cover")
}
s.curCover.Image = image
return nil
}
func (s *Scanner) handleFolder(fullPath string, stat os.FileInfo) error {
folder := &model.Folder{}
defer s.curFolders.Push(folder)
err := s.tx.Where("path = ?", fullPath).First(folder).Error
if !gorm.IsRecordNotFoundError(err) &&
stat.ModTime().Before(folder.UpdatedAt) {
// we found the record but it hasn't changed
return nil
}
folder.Path = fullPath
folder.Name = stat.Name()
s.tx.Save(folder)
return nil
}
func (s *Scanner) handleFolderCompletion(fullPath string, info *godirwalk.Dirent) error {
// in general in this function - if a model is not nil, then it
// has at least been looked up. if it has a id of 0, then it is
// a new record and needs to be inserted
//
var newCover bool
if s.curCover != nil && s.curCover.ID == 0 {
s.tx.Save(s.curCover)
newCover = true
}
if s.curAlbum != nil {
s.curAlbum.CoverID = s.curCover.ID
if newCover || s.curAlbum.ID == 0 {
s.tx.Save(s.curAlbum)
}
}
folder := s.curFolders.Pop()
if folder.ID == 0 || newCover {
folder.ParentID = s.curFolders.PeekID()
folder.CoverID = s.curCover.ID
folder.HasTracks = true
s.tx.Save(folder)
}
for _, track := range s.curTracks {
// not checking for a nil album here because if there are
// tracks, then we at least lookup up the album
track.AlbumID = s.curAlbum.ID
track.FolderID = folder.ID
s.tx.Save(track)
}
s.curTracks = nil
s.curCover = nil
s.curAlbum = nil
s.curAArtist = nil
log.Printf("processed folder `%s`\n", fullPath)
return nil
}
func (s *Scanner) handleTrack(fullPath string, stat os.FileInfo, mime, exten string) error {
//
// set track basics
track := &model.Track{}
modTime := stat.ModTime()
err := s.tx.Where("path = ?", fullPath).First(track).Error
if !gorm.IsRecordNotFoundError(err) &&
modTime.Before(track.UpdatedAt) {
// we found the record but it hasn't changed
return nil
}
tags, err := readTags(fullPath)
if err != nil {
return fmt.Errorf("when reading tags: %v", err)
}
trackNumber, totalTracks := tags.Track()
discNumber, totalDiscs := tags.Disc()
track.Path = fullPath
track.Title = tags.Title()
track.Artist = tags.Artist()
track.DiscNumber = discNumber
track.TotalDiscs = totalDiscs
track.TotalTracks = totalTracks
track.TrackNumber = trackNumber
track.Year = tags.Year()
track.Suffix = exten
track.ContentType = mime
track.Size = int(stat.Size())
track.FolderID = s.curFolders.PeekID()
//
// set album artist basics
s.curAArtist = &model.AlbumArtist{}
err = s.tx.Where("name = ?", tags.AlbumArtist()).
First(s.curAArtist).
Error
if gorm.IsRecordNotFoundError(err) {
s.curAArtist.Name = tags.AlbumArtist()
s.tx.Save(s.curAArtist)
}
track.AlbumArtistID = s.curAArtist.ID
//
// set album if this is the first track in the folder
if len(s.curTracks) > 0 {
s.curTracks = append(s.curTracks, track)
return nil
}
s.curTracks = append(s.curTracks, track)
//
s.curAlbum = &model.Album{}
directory, _ := path.Split(fullPath)
err = s.tx.
Where("path = ?", directory).
First(s.curAlbum).
Error
if !gorm.IsRecordNotFoundError(err) {
// we found the record
return nil
}
s.curAlbum.Path = directory
s.curAlbum.Title = tags.Album()
s.curAlbum.Year = tags.Year()
s.curAlbum.AlbumArtistID = s.curAArtist.ID
return nil
}
func (s *Scanner) handleItem(fullPath string, info *godirwalk.Dirent) error {
s.seenPaths[fullPath] = true
stat, err := os.Stat(fullPath)
if err != nil {
return fmt.Errorf("error stating: %v", err)
}
if info.IsDir() {
return s.handleFolder(fullPath, stat)
}
if isCover(fullPath) {
return s.handleCover(fullPath, stat)
}
if mime, exten, ok := isAudio(fullPath); ok {
return s.handleTrack(fullPath, stat, mime, exten)
}
return nil
}
func (s *Scanner) MigrateDB() error {
defer logElapsed(time.Now(), "migrating database")
s.db.Exec("PRAGMA foreign_keys = ON")
s.tx = s.db.Begin()
defer s.tx.Commit()
s.tx.AutoMigrate(
model.Album{},
model.AlbumArtist{},
model.Track{},
model.Cover{},
model.User{},
model.Setting{},
model.Play{},
model.Folder{},
)
s.tx.FirstOrCreate(&model.User{}, model.User{
Name: "admin",
Password: "admin",
IsAdmin: true,
})
return nil
}
func (s *Scanner) Start() error {
if atomic.LoadInt32(&IsScanning) == 1 {
return errors.New("already scanning")
}
atomic.StoreInt32(&IsScanning, 1)
defer atomic.StoreInt32(&IsScanning, 0)
defer logElapsed(time.Now(), "scanning")
s.db.Exec("PRAGMA foreign_keys = ON")
s.tx = s.db.Begin()
defer s.tx.Commit()
//
// start scan logic
err := godirwalk.Walk(s.musicPath, &godirwalk.Options{
Callback: s.handleItem,
PostChildrenCallback: s.handleFolderCompletion,
Unsorted: true,
})
if err != nil {
return errors.Wrap(err, "walking filesystem")
}
////
//// start cleaning logic
//log.Println("cleaning database")
//var tracks []*model.Track
//s.tx.Select("id, path").Find(&tracks)
//for _, track := range tracks {
// _, ok := s.seenPaths[track.Path]
// if ok {
// continue
// }
// s.tx.Delete(&track)
// log.Println("removed", track.Path)
//}
//// delete albums without tracks
//s.tx.Exec(`
//DELETE FROM albums
//WHERE (SELECT count(id)
//FROM tracks
//WHERE album_id = albums.id) = 0;
//`)
//// delete artists without tracks
//s.tx.Exec(`
//DELETE FROM album_artists
//WHERE (SELECT count(id)
//FROM albums
//WHERE album_artist_id = album_artists.id) = 0;
//`)
return nil
}