Merge pull request #636 from blackphantom39/empty-nad-spec

nad: do not try to unmarshal empty string

Author: stuggi

modules/common/networkattachment/networkattachment.go

@@ -152,36 +152,38 @@ func EnsureNetworksAnnotation(
 	annotationString := map[string]string{}
 	netAnnotations := []networkv1.NetworkSelectionElement{}
 	for _, nad := range nadList {
-		gateway := ""
 
-		var data interface{}
-		if err := json.Unmarshal([]byte(nad.Spec.Config), &data); err != nil {
-			return nil, fmt.Errorf("failed to unmarshal JSON data: %w", err)
-		}
+		gatewayReq := []net.IP{}
+		if nad.Spec.Config != "" {
 
-		// use jsonpath to parse the cni config
-		jp := jsonpath.New(nad.Name)
-		jp.AllowMissingKeys(true) // Allow missing keys, for when no gateway configured
+			var data interface{}
+			if err := json.Unmarshal([]byte(nad.Spec.Config), &data); err != nil {
+				return nil, fmt.Errorf("failed to unmarshal JSON data: %w", err)
+			}
 
-		// Parse the JSONPath template, for now just `ipam.gateway`
-		err := jp.Parse(`{.ipam.gateway}`)
-		if err != nil {
-			return annotationString, fmt.Errorf("parse template error: %w", err)
-		}
+			// use jsonpath to parse the cni config
+			jp := jsonpath.New(nad.Name)
+			jp.AllowMissingKeys(true) // Allow missing keys, for when no gateway configured
 
-		buf := new(bytes.Buffer)
-		// get the gateway from the config
-		err = jp.Execute(buf, data)
-		if err != nil {
-			return annotationString, fmt.Errorf("parse execute template against nad %+v error: %w", nad.Spec.Config, err)
-		}
+			// Parse the JSONPath template, for now just `ipam.gateway`
+			err := jp.Parse(`{.ipam.gateway}`)
+			if err != nil {
+				return annotationString, fmt.Errorf("parse template error: %w", err)
+			}
 
-		gateway = buf.String()
+			buf := new(bytes.Buffer)
+			// get the gateway from the config
+			err = jp.Execute(buf, data)
+			if err != nil {
+				return annotationString, fmt.Errorf("parse execute template against nad %+v error: %w", nad.Spec.Config, err)
+			}
 
-		gatewayReq := []net.IP{}
-		if gateway != "" {
-			gatewayReq = append(gatewayReq, net.ParseIP(gateway))
+			gateway := buf.String()
+
+			if gateway != "" {
+				gatewayReq = append(gatewayReq, net.ParseIP(gateway))
 
+			}
 		}
 
 		netAnnotations = append(

modules/common/networkattachment/networkattachment_test.go

@@ -183,6 +183,15 @@ func TestEnsureNetworksAnnotation(t *testing.T) {
 			nadList: []networkv1.NetworkAttachmentDefinition{},
 			want:    map[string]string{networkv1.NetworkAttachmentAnnot: "[]"},
 		},
+		{
+			name: "Empty NetworkAttachmentDefinition spec",
+			nadList: []networkv1.NetworkAttachmentDefinition{
+				{
+					ObjectMeta: metav1.ObjectMeta{Name: "one", Namespace: "foo"},
+				},
+			},
+			want: map[string]string{networkv1.NetworkAttachmentAnnot: "[{\"name\":\"one\",\"namespace\":\"foo\",\"interface\":\"one\"}]"},
+		},
 		{
 			name: "Single network",
 			nadList: []networkv1.NetworkAttachmentDefinition{