Supporting index annotations in domain structs

domain/album.go

@@ -6,13 +6,13 @@ type Album struct {
 	Id           string
 	Name         string
 	ArtistId     string `parent:"artist"`
-	CoverArtPath string // TODO http://stackoverflow.com/questions/13795842/linking-itunes-itc2-files-and-ituneslibrary-xml
+	CoverArtPath string
 	CoverArtId   string
 	Artist       string
 	AlbumArtist  string
-	Year         int
+	Year         int `idx:"Year"`
 	Compilation  bool
-	Starred      bool
+	Starred      bool `idx:"Starred"`
 	PlayCount    int
 	PlayDate     time.Time
 	Rating       int

persistence/ledis_repository.go

@@ -7,6 +7,8 @@ import (
 	"reflect"
 	"strings"
 
+	"time"
+
 	"github.com/deluan/gosonic/domain"
 	"github.com/deluan/gosonic/utils"
 	"github.com/siddontang/ledisdb/ledis"
@@ -18,6 +20,7 @@ type ledisRepository struct {
 	fieldNames    []string
 	parentTable   string
 	parentIdField string
+	indexes       map[string]string
 }
 
 func (r *ledisRepository) init(table string, entity interface{}) {
@@ -31,7 +34,24 @@ func (r *ledisRepository) init(table string, entity interface{}) {
 		r.fieldNames[i] = k
 		i++
 	}
-	r.parentTable, r.parentIdField, _ = r.getParent(entity)
+	r.parseAnnotations(entity)
+}
+
+func (r *ledisRepository) parseAnnotations(entity interface{}) {
+	r.indexes = make(map[string]string)
+	dt := reflect.TypeOf(entity).Elem()
+	for i := 0; i < dt.NumField(); i++ {
+		f := dt.Field(i)
+		table := f.Tag.Get("parent")
+		if table != "" {
+			r.parentTable = table
+			r.parentIdField = f.Name
+		}
+		idx := f.Tag.Get("idx")
+		if idx != "" {
+			r.indexes[idx] = f.Name
+		}
+	}
 }
 
 // TODO Use annotations to specify fields to be used
@@ -123,6 +143,18 @@ func (r *ledisRepository) saveOrUpdate(id string, entity interface{}) error {
 
 	}
 
+	for idx, fn := range r.indexes {
+		idxName := fmt.Sprintf("%s:idx:%s", r.table, idx)
+		if _, err := Db().ZRem([]byte(idxName), []byte(id)); err != nil {
+			return err
+		}
+		score := calcScore(entity, fn)
+		sidx := ledis.ScorePair{score, []byte(id)}
+		if _, err = Db().ZAdd([]byte(idxName), sidx); err != nil {
+			return err
+		}
+	}
+
 	sid := ledis.ScorePair{0, []byte(id)}
 	if _, err = Db().ZAdd([]byte(allKey), sid); err != nil {
 		return err
@@ -134,6 +166,26 @@ func (r *ledisRepository) saveOrUpdate(id string, entity interface{}) error {
 	return nil
 }
 
+func calcScore(entity interface{}, fieldName string) int64 {
+	var score int64
+
+	dv := reflect.ValueOf(entity).Elem()
+	v := dv.FieldByName(fieldName)
+
+	switch v.Interface().(type) {
+	case int:
+		score = v.Int()
+	case bool:
+		if v.Bool() {
+			score = 1
+		}
+	case time.Time:
+		score = utils.ToMillis(v.Interface().(time.Time))
+	}
+
+	return score
+}
+
 func (r *ledisRepository) getParentRelationKey(entity interface{}) string {
 	parentId := r.getParentId(entity)
 	if parentId != "" {
@@ -142,22 +194,6 @@ func (r *ledisRepository) getParentRelationKey(entity interface{}) string {
 	return ""
 }
 
-// TODO Optimize
-func (r *ledisRepository) getParent(entity interface{}) (table string, idField string, id string) {
-	dt := reflect.TypeOf(entity).Elem()
-	for i := 0; i < dt.NumField(); i++ {
-		f := dt.Field(i)
-		table = f.Tag.Get("parent")
-		if table != "" {
-			idField = f.Name
-			dv := reflect.ValueOf(entity).Elem()
-			id = dv.FieldByName(f.Name).String()
-			return
-		}
-	}
-	return
-}
-
 func (r *ledisRepository) getParentId(entity interface{}) string {
 	if r.parentTable != "" {
 		dv := reflect.ValueOf(entity).Elem()

persistence/ledis_repository_test.go

@@ -5,14 +5,20 @@ import (
 	"strconv"
 	"testing"
 
+	"time"
+
 	"github.com/deluan/gosonic/tests"
+	"github.com/deluan/gosonic/utils"
 	. "github.com/smartystreets/goconvey/convey"
 )
 
 type TestEntity struct {
 	Id       string
 	Name     string
-	ParentId string `parent:"parent"`
+	ParentId string    `parent:"parent"`
+	Year     time.Time `idx:"ByYear"`
+	Count    int       `idx:"ByCount"`
+	Flag     bool      `idx:"ByFlag"`
 }
 
 func shouldBeEqual(actualStruct interface{}, expectedStruct ...interface{}) string {
@@ -30,6 +36,55 @@ func createRepo() *ledisRepository {
 func TestBaseRepository(t *testing.T) {
 	tests.Init(t, false)
 
+	Convey("Subject: Annotations", t, func() {
+		repo := createRepo()
+		Convey("It should parse the parent table definition", func() {
+			So(repo.parentTable, ShouldEqual, "parent")
+			So(repo.parentIdField, ShouldEqual, "ParentId")
+		})
+		Convey("It should parse the definded indexes", func() {
+			So(repo.indexes, ShouldHaveLength, 3)
+			So(repo.indexes["ByYear"], ShouldEqual, "Year")
+			So(repo.indexes["ByFlag"], ShouldEqual, "Flag")
+			So(repo.indexes["ByCount"], ShouldEqual, "Count")
+		})
+	})
+
+	Convey("Subject: calcScore", t, func() {
+		repo := createRepo()
+
+		Convey("It should create an int score", func() {
+			def := repo.indexes["ByCount"]
+			entity := &TestEntity{Count: 10}
+			score := calcScore(entity, def)
+
+			So(score, ShouldEqual, 10)
+		})
+		Convey("It should create a boolean score", func() {
+			def := repo.indexes["ByFlag"]
+			Convey("Value false", func() {
+				entity := &TestEntity{Flag: false}
+				score := calcScore(entity, def)
+
+				So(score, ShouldEqual, 0)
+			})
+			Convey("Value true", func() {
+				entity := &TestEntity{Flag: true}
+				score := calcScore(entity, def)
+
+				So(score, ShouldEqual, 1)
+			})
+		})
+		Convey("It should create a time score", func() {
+			def := repo.indexes["ByYear"]
+			now := time.Now()
+			entity := &TestEntity{Year: now}
+			score := calcScore(entity, def)
+
+			So(score, ShouldEqual, utils.ToMillis(now))
+		})
+	})
+
 	Convey("Subject: NewId", t, func() {
 		repo := createRepo()
 
@@ -68,7 +123,7 @@ func TestBaseRepository(t *testing.T) {
 			repo := createRepo()
 
 			Convey("When I save a new entity and a parent", func() {
-				entity := &TestEntity{"123", "My Name", "ABC"}
+				entity := &TestEntity{Id: "123", Name: "My Name", ParentId: "ABC", Year: time.Now()}
 				err := repo.saveOrUpdate("123", entity)
 				Convey("Then saving the entity shouldn't return any errors", func() {
 					So(err, ShouldBeNil)
@@ -97,11 +152,11 @@ func TestBaseRepository(t *testing.T) {
 
 		Convey("Given a table with one entity", func() {
 			repo := createRepo()
-			entity := &TestEntity{"111", "One Name", "AAA"}
+			entity := &TestEntity{Id: "111", Name: "One Name", ParentId: "AAA"}
 			repo.saveOrUpdate(entity.Id, entity)
 
 			Convey("When I save an entity with a different Id", func() {
-				newEntity := &TestEntity{"222", "Another Name", "AAA"}
+				newEntity := &TestEntity{Id: "222", Name: "Another Name", ParentId: "AAA"}
 				repo.saveOrUpdate(newEntity.Id, newEntity)
 
 				Convey("Then the number of entities should be 2", func() {
@@ -112,7 +167,7 @@ func TestBaseRepository(t *testing.T) {
 			})
 
 			Convey("When I save an entity with the same Id", func() {
-				newEntity := &TestEntity{"111", "New Name", "AAA"}
+				newEntity := &TestEntity{Id: "111", Name: "New Name", ParentId: "AAA"}
 				repo.saveOrUpdate(newEntity.Id, newEntity)
 
 				Convey("Then the number of entities should be 1", func() {
@@ -133,7 +188,7 @@ func TestBaseRepository(t *testing.T) {
 		Convey("Given a table with 3 entities", func() {
 			repo := createRepo()
 			for i := 1; i <= 3; i++ {
-				e := &TestEntity{strconv.Itoa(i), fmt.Sprintf("Name %d", i), "AAA"}
+				e := &TestEntity{Id: strconv.Itoa(i), Name: fmt.Sprintf("Name %d", i), ParentId: "AAA"}
 				repo.saveOrUpdate(e.Id, e)
 			}