[#345] netmap: Implement an iterator over node attributes

Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>

netmap/node_info.go

@@ -408,8 +408,21 @@ func (x NodeInfo) NumberOfAttributes() int {
 	return len(x.m.GetAttributes())
 }
 
+// Attributes returns an iterator over node attributes.
+func (x NodeInfo) Attributes() iter.Seq2[string, string] {
+	return func(yield func(string, string) bool) {
+		a := x.m.GetAttributes()
+		for i := range a {
+			if !yield(a[i].GetKey(), a[i].GetValue()) {
+				break
+			}
+		}
+	}
+}
+
 // IterateAttributes iterates over all node attributes and passes the into f.
 // Handler MUST NOT be nil.
+// Deprecated: use [NodeInfo.Attributes] instead.
 func (x NodeInfo) IterateAttributes(f func(key, value string)) {
 	a := x.m.GetAttributes()
 	for i := range a {

netmap/node_info_test.go

@@ -46,6 +46,47 @@ func TestNodeInfo_NetworkEndpoints(t *testing.T) {
 	require.Equal(t, []string{"1", "2", "3"}, res)
 }
 
+func TestNodeInfo_Attributes(t *testing.T) {
+	t.Run("empty", func(t *testing.T) {
+		var n NodeInfo
+		for range n.Attributes() {
+			t.Fatalf("handler is called, but it shouldn't")
+		}
+	})
+
+	var n NodeInfo
+	n.SetAttribute("key1", "value1")
+	n.SetAttribute("key2", "value2")
+	n.SetAttribute("key3", "value3")
+
+	t.Run("break", func(t *testing.T) {
+		var res [][2]string
+		for k, v := range n.Attributes() {
+			if k == "key2" {
+				break
+			}
+			res = append(res, [2]string{k, v})
+		}
+		require.Equal(t, [][2]string{{"key1", "value1"}}, res)
+	})
+	t.Run("continue", func(t *testing.T) {
+		var res [][2]string
+		for k, v := range n.Attributes() {
+			if k == "key2" {
+				continue
+			}
+			res = append(res, [2]string{k, v})
+		}
+		require.Equal(t, [][2]string{{"key1", "value1"}, {"key3", "value3"}}, res)
+	})
+
+	var res [][2]string
+	for k, v := range n.Attributes() {
+		res = append(res, [2]string{k, v})
+	}
+	require.Equal(t, [][2]string{{"key1", "value1"}, {"key2", "value2"}, {"key3", "value3"}}, res)
+}
+
 func TestNodeInfo_SetAttribute(t *testing.T) {
 	var n NodeInfo