Insensitive case for allow-empty value.

pkg/provider/label/internal/nodes_metadata.go

@@ -52,7 +52,7 @@ func addMetadata(rootType reflect.Type, node *Node) error {
 			return fmt.Errorf("node %s (type %s) must have children", node.Name, fType)
 		}
 
-		node.Disabled = len(node.Value) > 0 && node.Value != "true" && field.Tag.Get(TagLabel) == "allowEmpty"
+		node.Disabled = len(node.Value) > 0 && !strings.EqualFold(node.Value, "true") && field.Tag.Get(TagLabel) == "allowEmpty"
 	}
 
 	if len(node.Children) == 0 {

pkg/provider/label/internal/nodes_metadata_test.go

@@ -451,6 +451,33 @@ func TestAddMetadata(t *testing.T) {
 				},
 			},
 		},
+		{
+			desc: "level 2, struct with allowEmpty, value true with case variation",
+			tree: &Node{
+				Name: "traefik",
+				Children: []*Node{
+					{Name: "Foo", Value: "TruE"},
+				},
+			},
+			structure: struct {
+				Foo struct {
+					Bar string
+				} `label:"allowEmpty"`
+			}{
+				Foo: struct {
+					Bar string
+				}{},
+			},
+			expected: expected{
+				node: &Node{
+					Name: "traefik",
+					Kind: reflect.Struct,
+					Children: []*Node{
+						{Name: "Foo", FieldName: "Foo", Value: "TruE", Kind: reflect.Struct},
+					},
+				},
+			},
+		},
 		{
 			desc: "level 2, struct with allowEmpty, value false",
 			tree: &Node{