Merge remote-tracking branch 'import/main'

8 files changed, 438 insertions, 0 deletions

diff --git a/cmd/mpd-scrobbler/README.org b/cmd/mpd-scrobbler/README.org
new file mode 100644
index 0000000..8c0a7d9
--- /dev/null
+++ b/cmd/mpd-scrobbler/README.org
@@ -0,0 +1,22 @@
+#+TITLE: mpd-stats
+
+Log played songs to extract statistics. This is similar to what libre.fm used to do, but locally.
+
+* Logging
+Collect logs from mpd. A log record is composed of the following fields:
+- id: UUID
+- song's name: the name of the song
+- song's album: the name of the album
+- song's artist: the name of the artist
+- song's duration: the duration of the song
+- date: date the song was played
+
+The logs are recorded in a database (sqlite3 to start).
+* Install
+The Makefile assumes the system is running Linux and systemd.
+
+Run =make install=. This will:
+- install the binary in your =GOPATH= (using =go install=)
+- install a systemd unit file under =$HOME/.config/systemd/user=
+- reload systemd unit files
+- start the service
diff --git a/cmd/mpd-scrobbler/main.go b/cmd/mpd-scrobbler/main.go
new file mode 100644
index 0000000..c2693a4
--- /dev/null
+++ b/cmd/mpd-scrobbler/main.go
@@ -0,0 +1,57 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+
+	"golang.fcuny.net/mpd-stats/internal/scrobbler"
+)
+
+func main() {
+	var (
+		mpdHost = flag.String("host", "localhost", "The MPD server to connect  to (default: localhost)")
+		mpdPort = flag.Int("port", 6600, "The TCP port of the MPD server to connect to (default: 6600)")
+	)
+	flag.Parse()
+
+	net := "tcp"
+	addr := fmt.Sprintf("%s:%d", *mpdHost, *mpdPort)
+
+	dbpath, err := getDbPath()
+	if err != nil {
+		log.Fatalf("failed to get the path to the database: %v", err)
+	}
+
+	s, err := scrobbler.NewScrobbler(net, addr, dbpath)
+	if err != nil {
+		log.Fatalf("failed to create a client: %v", err)
+	}
+
+	defer func() {
+		if err := s.Close(); err != nil {
+			log.Fatalf("failed to close the scrobbler: %v", err)
+		}
+	}()
+
+	s.Run()
+}
+
+func getDbPath() (string, error) {
+	xch := os.Getenv("XDG_CONFIG_HOME")
+	if xch == "" {
+		home := os.Getenv("HOME")
+		xch = filepath.Join(home, ".config")
+	}
+
+	scrobblerHome := filepath.Join(xch, "mpd-scrobbler")
+	if _, err := os.Stat(scrobblerHome); os.IsNotExist(err) {
+		if err := os.Mkdir(scrobblerHome, 0755); err != nil {
+			return "", err
+		}
+	}
+
+	return filepath.Join(scrobblerHome, "scrobbler.sql"), nil
+}
diff --git a/internal/mpd/mpd.go b/internal/mpd/mpd.go
new file mode 100644
index 0000000..5b57ee4
--- /dev/null
+++ b/internal/mpd/mpd.go
@@ -0,0 +1,48 @@
+package mpd
+
+import (
+	"log"
+	"time"
+
+	"github.com/fhs/gompd/v2/mpd"
+)
+
+type Player struct {
+	Watcher *mpd.Watcher
+	Client  *mpd.Client
+}
+
+func NewPlayer(net string, addr string) (*Player, error) {
+	var (
+		p   Player
+		err error
+	)
+
+	p.Watcher, err = mpd.NewWatcher(net, addr, "", "player")
+	if err != nil {
+		log.Fatalf("failed to create a watcher: %v", err)
+	}
+
+	p.Client, err = mpd.Dial(net, addr)
+	if err != nil {
+		log.Fatalf("failed to start mpd client: %v", err)
+	}
+
+	go func() {
+		for range time.Tick(30 * time.Second) {
+			p.Client.Ping()
+		}
+	}()
+
+	return &p, nil
+}
+
+func (p *Player) Close() error {
+	if err := p.Watcher.Close(); err != nil {
+		return err
+	}
+	if err := p.Client.Close(); err != nil {
+		return err
+	}
+	return nil
+}
diff --git a/internal/scrobbler/db.go b/internal/scrobbler/db.go
new file mode 100644
index 0000000..5f80aa4
--- /dev/null
+++ b/internal/scrobbler/db.go
@@ -0,0 +1,55 @@
+package scrobbler
+
+import (
+	"database/sql"
+	"fmt"
+	"os"
+
+	_ "github.com/mattn/go-sqlite3"
+)
+
+func initdb(dbpath string) error {
+	if _, err := os.Stat(dbpath); err == nil {
+		return fmt.Errorf("%s already exists", dbpath)
+	}
+
+	db, err := sql.Open("sqlite3", dbpath)
+	if err != nil {
+		return err
+	}
+	defer db.Close()
+
+	sqlStmt := `create table records (id text primary key,
+				title text,
+				artist text,
+                album text,
+                duration int,
+                playtime int,
+                time timestamp
+			);`
+
+	_, err = db.Exec(sqlStmt)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func opendatabase(dbpath string) (*sql.DB, error) {
+	var err error
+	_, err = os.Stat(dbpath)
+
+	if err != nil {
+		if err := initdb(dbpath); err != nil {
+			return nil, err
+		}
+	}
+
+	db, err := sql.Open("sqlite3", dbpath)
+	if err != nil {
+		return nil, fmt.Errorf("unable to open database: %s", err)
+	}
+
+	return db, nil
+}
diff --git a/internal/scrobbler/record.go b/internal/scrobbler/record.go
new file mode 100644
index 0000000..e252fd3
--- /dev/null
+++ b/internal/scrobbler/record.go
@@ -0,0 +1,42 @@
+package scrobbler
+
+import (
+	"strconv"
+	"time"
+
+	"github.com/fhs/gompd/v2/mpd"
+	"github.com/google/uuid"
+)
+
+type Record struct {
+	Id        uuid.UUID
+	Title     string
+	Album     string
+	Artist    string
+	Duration  time.Duration
+	Timestamp time.Time
+}
+
+func NewRecord(attrs mpd.Attrs) (*Record, error) {
+	record := Record{
+		Id:        uuid.New(),
+		Title:     attrs["Title"],
+		Album:     attrs["Album"],
+		Artist:    attrs["Artist"],
+		Timestamp: time.Now(),
+	}
+
+	dur, err := strconv.ParseFloat(attrs["duration"], 32)
+	if err != nil {
+		return nil, err
+	}
+
+	record.Duration = time.Second * time.Duration(dur)
+	return &record, nil
+}
+
+func (r *Record) EqualAttrs(attrs mpd.Attrs) bool {
+	return r.Title == attrs["Title"] &&
+		r.Album == attrs["Album"] &&
+		r.Artist == attrs["Artist"]
+}
diff --git a/internal/scrobbler/record_test.go b/internal/scrobbler/record_test.go
new file mode 100644
index 0000000..3bf8554
--- /dev/null
+++ b/internal/scrobbler/record_test.go
@@ -0,0 +1,53 @@
+package scrobbler
+
+import (
+	"testing"
+
+	"github.com/fhs/gompd/v2/mpd"
+)
+
+func TestNewRecord(t *testing.T) {
+	song := mpd.Attrs{
+		"Artist":   "Nine Inch Nails",
+		"Album":    "The Downward Spiral",
+		"Title":    "Reptile",
+		"duration": "411.00",
+	}
+
+	record, err := NewRecord(song)
+	if err != nil {
+		t.Errorf("NewRecord returned an error: %s", err)
+	}
+	if record == nil {
+		t.Errorf("NewRecord returned nil record")
+	}
+}
+
+func TestRecordEqualAttrs(t *testing.T) {
+	s1 := mpd.Attrs{
+		"Artist":   "Nine Inch Nails",
+		"Album":    "The Downward Spiral",
+		"Title":    "Reptile",
+		"duration": "411.00",
+	}
+
+	s2 := mpd.Attrs{
+		"Artist":   "Nine Inch Nails",
+		"Album":    "The Downward Spiral",
+		"Title":    "Closer",
+		"duration": "373.00",
+	}
+
+	r, err := NewRecord(s1)
+	if err != nil {
+		t.Errorf("NewRecord returned an error: %s", err)
+	}
+
+	if !r.EqualAttrs(s1) {
+		t.Errorf("EqualAttrs expected true got false")
+	}
+
+	if r.EqualAttrs(s2) {
+		t.Errorf("EqualAttrs expected false got true")
+	}
+}
diff --git a/internal/scrobbler/scrobbler.go b/internal/scrobbler/scrobbler.go
new file mode 100644
index 0000000..f0f9d0e
--- /dev/null
+++ b/internal/scrobbler/scrobbler.go
@@ -0,0 +1,118 @@
+package scrobbler
+
+import (
+	"database/sql"
+	"log"
+	"time"
+
+	"golang.fcuny.net/mpd-stats/internal/mpd"
+)
+
+type Scrobbler struct {
+	player *mpd.Player
+	db     *sql.DB
+}
+
+func NewScrobbler(net string, addr string, dbpath string) (*Scrobbler, error) {
+	p, err := mpd.NewPlayer(net, addr)
+	if err != nil {
+		return nil, err
+	}
+
+	db, err := opendatabase(dbpath)
+	if err != nil {
+		return nil, err
+	}
+
+	s := Scrobbler{
+		player: p,
+		db:     db,
+	}
+
+	return &s, nil
+}
+
+func (s *Scrobbler) Close() error {
+	return s.player.Close()
+}
+
+func (s *Scrobbler) Run() error {
+	var (
+		currentRecord  *Record
+		previousRecord *Record
+	)
+
+	for {
+		e := <-s.player.Watcher.Event
+		if e != "" {
+			status, err := s.player.Client.Status()
+			if err != nil {
+				log.Printf("could not read the status: %v", err)
+			}
+
+			if status["state"] == "stop" {
+				if currentRecord != nil {
+					if err := s.update(currentRecord); err != nil {
+						log.Printf("failed to update record %s: %s", currentRecord.Id, err)
+					}
+					currentRecord = nil
+				}
+				continue
+			}
+
+			attrs, err := s.player.Client.CurrentSong()
+			if err != nil {
+				log.Printf("could not get current song: %v", err)
+			}
+
+			if currentRecord == nil {
+				currentRecord, err = NewRecord(attrs)
+				if err != nil {
+					log.Printf("could not create a log: %v", err)
+				}
+				previousRecord = currentRecord
+				if err := s.save(currentRecord); err != nil {
+					log.Printf("failed to insert record %s: %s", currentRecord.Id, err)
+				}
+				continue
+			}
+
+			if !currentRecord.EqualAttrs(attrs) {
+				currentRecord, err = NewRecord(attrs)
+				if err != nil {
+					log.Printf("could not create a log: %v", err)
+				}
+			}
+
+			if currentRecord.Id != previousRecord.Id {
+				if err := s.update(previousRecord); err != nil {
+					log.Printf("failed to update record %s: %s", previousRecord.Id, err)
+				}
+				previousRecord = currentRecord
+				s.save(currentRecord)
+			}
+		}
+	}
+}
+
+func (s *Scrobbler) save(record *Record) error {
+	_, err := s.db.Exec("insert into records(id, title, artist, album, duration, playtime, time) values(?, ?, ?, ?, ?, 0, ?)",
+		record.Id,
+		record.Title,
+		record.Artist,
+		record.Album,
+		int(record.Duration.Seconds()),
+		record.Timestamp,
+	)
+	return err
+}
+
+func (s *Scrobbler) update(record *Record) error {
+	tnow := time.Now()
+	playtime := tnow.Sub(record.Timestamp).Seconds()
+	_, err := s.db.Exec("update records set playtime = ? where id = ?",
+		int(playtime),
+		record.Id,
+	)
+	return err
+}
diff --git a/systemd/mpd-scrobbler.service b/systemd/mpd-scrobbler.service
new file mode 100644
index 0000000..7990208
--- /dev/null
+++ b/systemd/mpd-scrobbler.service
@@ -0,0 +1,43 @@
+[Unit]
+Description=mpd scrobbler
+Documentation=https://git.fcuny.net/fcuny/mpd-stats
+ConditionFileIsExecutable=%h/workspace/go/bin/mpd-scrobbler
+
+[Service]
+ExecStart=%h/workspace/go/bin/mpd-scrobbler
+Restart=on-failure
+
+PrivateTmp=yes
+ProtectSystem=strict
+NoNewPrivileges=yes
+ProtectHome=yes
+
+# Prohibit access to any kind of namespacing:
+RestrictNamespaces=yes
+
+# Make cgroup file system hierarchy inaccessible:
+ProtectControlGroups=yes
+
+# Deny access to other user’s information in /proc:
+ProtectProc=invisible
+
+# Only allow access to /proc pid files, no other files:
+ProcSubset=pid
+
+# This daemon must not create any new files, but set the umask to 077 just in case.
+UMask=077
+
+# Filter dangerous system calls. The following is listed as safe basic choice
+# in systemd.exec(5):
+SystemCallArchitectures=native
+SystemCallFilter=@system-service
+SystemCallFilter=~@privileged
+SystemCallFilter=~@resources
+SystemCallErrorNumber=EPERM
+
+# Deny kernel execution domain changing:
+LockPersonality=yes
+
+# Deny memory mappings that are writable and executable:
+MemoryDenyWriteExecute=yes
+