feat(finder): support skip, limit and sort (#77)

Co-authored-by: lifeng.lif <[email protected]>

Author: lifeng342

bsonx/bsonx.go

@@ -89,3 +89,23 @@ func dToM(d bson.D) bson.M {
 	}
 	return m
 }
+
+// StringSortToBsonD transform string sort to bson D
+// "-created_at" => bson.D{{"created_at", -1}}
+// []string{"age", "-created_at"} => bson.D{{"age", 1}, {"created_at", -1}}
+func StringSortToBsonD(sorts ...string) bson.D {
+	var res bson.D
+	for _, sort := range sorts {
+		if len(sort) == 0 || sort == "-" {
+			continue
+		}
+
+		if sort[0] == '-' {
+			res = append(res, bson.E{Key: sort[1:], Value: -1})
+		} else {
+			res = append(res, bson.E{Key: sort, Value: 1})
+		}
+	}
+
+	return res
+}

bsonx/bsonx_test.go

@@ -62,3 +62,40 @@ func TestA(t *testing.T) {
 	}
 
 }
+
+func TestStringSortToBsonD(t *testing.T) {
+	testCases := []struct {
+		name  string
+		value any
+		want  bson.D
+	}{
+		{
+			name:  "empty string",
+			value: []string{""},
+			want:  nil,
+		},
+		{
+			name:  "only minus sign",
+			value: []string{"-"},
+			want:  nil,
+		},
+		{
+			name:  "one sort",
+			value: []string{"-created_at"},
+			want:  bson.D{{Key: "created_at", Value: -1}},
+		},
+		{
+			name:  "two sort",
+			value: []string{"age", "-created_at"},
+			want:  bson.D{{Key: "age", Value: 1}, {Key: "created_at", Value: -1}},
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			w, _ := bson.Marshal(tc.want)
+			v, _ := bson.Marshal(StringSortToBsonD(tc.value.([]string)...))
+			assert.Equal(t, string(w), string(v))
+		})
+	}
+}

finder/finder.go

@@ -45,6 +45,9 @@ type Finder[T any] struct {
 	modelHook   any
 	beforeHooks []beforeHookFn
 	afterHooks  []afterHookFn[T]
+
+	skip, limit int64
+	sort        any
 }
 
 func (f *Finder[T]) RegisterBeforeHooks(hooks ...beforeHookFn) *Finder[T] {
@@ -66,6 +69,21 @@ func (f *Finder[T]) Filter(filter any) *Finder[T] {
 	return f
 }
 
+func (f *Finder[T]) Limit(limit int64) *Finder[T] {
+	f.limit = limit
+	return f
+}
+
+func (f *Finder[T]) Skip(skip int64) *Finder[T] {
+	f.skip = skip
+	return f
+}
+
+func (f *Finder[T]) Sort(sort any) *Finder[T] {
+	f.sort = sort
+	return f
+}
+
 func (f *Finder[T]) Updates(update any) *Finder[T] {
 	f.updates = update
 	return f
@@ -109,6 +127,10 @@ func (f *Finder[T]) postActionHandler(ctx context.Context, globalOpContext *oper
 }
 
 func (f *Finder[T]) FindOne(ctx context.Context, opts ...options.Lister[options.FindOneOptions]) (*T, error) {
+	if f.sort != nil {
+		opts = append(opts, options.FindOne().SetSort(f.sort))
+	}
+
 	t := new(T)
 
 	globalOpContext := operation.NewOpContext(f.collection, operation.WithDoc(t), operation.WithFilter(f.filter), operation.WithMongoOptions(opts), operation.WithModelHook(f.modelHook))
@@ -131,6 +153,16 @@ func (f *Finder[T]) FindOne(ctx context.Context, opts ...options.Lister[options.
 }
 
 func (f *Finder[T]) Find(ctx context.Context, opts ...options.Lister[options.FindOptions]) ([]*T, error) {
+	if f.sort != nil {
+		opts = append(opts, options.Find().SetSort(f.sort))
+	}
+	if f.skip != 0 {
+		opts = append(opts, options.Find().SetSkip(f.skip))
+	}
+	if f.limit != 0 {
+		opts = append(opts, options.Find().SetLimit(f.limit))
+	}
+
 	t := make([]*T, 0)
 
 	opContext := operation.NewOpContext(f.collection, operation.WithFilter(f.filter), operation.WithMongoOptions(opts), operation.WithModelHook(f.modelHook))