diff --git a/api/layer/notifications_test.go b/api/layer/notifications_test.go
new file mode 100644
index 0000000..69abb9d
--- /dev/null
+++ b/api/layer/notifications_test.go
@@ -0,0 +1,115 @@
+package layer
+
+import (
+	"testing"
+
+	"github.com/nspcc-dev/neofs-s3-gw/api/data"
+	"github.com/nspcc-dev/neofs-s3-gw/api/errors"
+	"github.com/stretchr/testify/require"
+)
+
+func TestFilterSubjects(t *testing.T) {
+	config := &data.NotificationConfiguration{
+		QueueConfigurations: []data.QueueConfiguration{
+			{
+				ID:       "test1",
+				QueueArn: "test1",
+				Events:   []string{EventObjectCreated, EventObjectRemovedDelete},
+			},
+			{
+				ID:       "test2",
+				QueueArn: "test2",
+				Events:   []string{EventObjectTagging},
+				Filter: data.Filter{Key: data.Key{FilterRules: []data.FilterRule{
+					{Name: "prefix", Value: "dir/"},
+					{Name: "suffix", Value: ".png"},
+				}}},
+			},
+		},
+	}
+
+	t.Run("no topics because suitable events not found", func(t *testing.T) {
+		topics := filterSubjects(config, EventObjectACLPut, "dir/a.png")
+		require.Empty(t, topics)
+	})
+
+	t.Run("no topics because of not suitable prefix", func(t *testing.T) {
+		topics := filterSubjects(config, EventObjectTaggingPut, "dirw/cat.png")
+		require.Empty(t, topics)
+	})
+
+	t.Run("no topics because of not suitable suffix", func(t *testing.T) {
+		topics := filterSubjects(config, EventObjectTaggingPut, "a.jpg")
+		require.Empty(t, topics)
+	})
+
+	t.Run("filter topics from queue configs without prefix suffix filter and exact event", func(t *testing.T) {
+		topics := filterSubjects(config, EventObjectCreatedPut, "dir/a.png")
+		require.Contains(t, topics, "test1")
+		require.Len(t, topics, 1)
+		require.Equal(t, topics["test1"], "test1")
+	})
+
+	t.Run("filter topics from queue configs with prefix suffix filter and '*' ending event", func(t *testing.T) {
+		topics := filterSubjects(config, EventObjectTaggingPut, "dir/a.png")
+		require.Contains(t, topics, "test2")
+		require.Len(t, topics, 1)
+		require.Equal(t, topics["test2"], "test2")
+	})
+}
+
+func TestCheckRules(t *testing.T) {
+	t.Run("correct rules with prefix and suffix", func(t *testing.T) {
+		rules := []data.FilterRule{
+			{Name: "prefix", Value: "asd"},
+			{Name: "suffix", Value: "asd"},
+		}
+		err := checkRules(rules)
+		require.NoError(t, err)
+	})
+
+	t.Run("correct rules with prefix", func(t *testing.T) {
+		rules := []data.FilterRule{
+			{Name: "prefix", Value: "asd"},
+		}
+		err := checkRules(rules)
+		require.NoError(t, err)
+	})
+
+	t.Run("correct rules with suffix", func(t *testing.T) {
+		rules := []data.FilterRule{
+			{Name: "suffix", Value: "asd"},
+		}
+		err := checkRules(rules)
+		require.NoError(t, err)
+	})
+
+	t.Run("incorrect rules with wrong name", func(t *testing.T) {
+		rules := []data.FilterRule{
+			{Name: "prefix", Value: "sdf"},
+			{Name: "sfx", Value: "asd"},
+		}
+		err := checkRules(rules)
+		require.ErrorIs(t, err, errors.GetAPIError(errors.ErrFilterNameInvalid))
+	})
+
+	t.Run("incorrect rules with repeating suffix", func(t *testing.T) {
+		rules := []data.FilterRule{
+			{Name: "suffix", Value: "asd"},
+			{Name: "suffix", Value: "asdf"},
+			{Name: "prefix", Value: "jk"},
+		}
+		err := checkRules(rules)
+		require.ErrorIs(t, err, errors.GetAPIError(errors.ErrFilterNameSuffix))
+	})
+
+	t.Run("incorrect rules with repeating prefix", func(t *testing.T) {
+		rules := []data.FilterRule{
+			{Name: "suffix", Value: "ds"},
+			{Name: "prefix", Value: "asd"},
+			{Name: "prefix", Value: "asdf"},
+		}
+		err := checkRules(rules)
+		require.ErrorIs(t, err, errors.GetAPIError(errors.ErrFilterNamePrefix))
+	})
+}