Fix: domain trie crash if not match in #758 (#762)

component/trie/domain.go

@@ -98,7 +98,7 @@ func (t *DomainTrie) Search(domain string) *Node {
 
 	n := t.search(t.root, parts)
 
-	if n.Data == nil {
+	if n == nil || n.Data == nil {
 		return nil
 	}
 

component/trie/domain_test.go

@@ -27,6 +27,7 @@ func TestTrie_Basic(t *testing.T) {
 	assert.NotNil(t, tree.Insert("", localIP))
 	assert.Nil(t, tree.Search(""))
 	assert.NotNil(t, tree.Search("localhost"))
+	assert.Nil(t, tree.Search("www.google.com"))
 }
 
 func TestTrie_Wildcard(t *testing.T) {