no-op on nil

json_rpc/clients/websocketclient.nim

@@ -116,6 +116,7 @@ when useNews:
       # TODO: This is a hack, because the table might be case sensitive. Ideally strtabs module has
       # to be extended with case insensitive accessors.
       headers["Origin"] = "http://localhost"
+    if not isNil(client.getHeaders):
       for header in client.getHeaders():
         headers[header[0]] = header[1]
     client.transport = await newWebSocket(uri, headers)