getRootFilePath method
Implementation
Future<String> getRootFilePath(Fetcher fetcher) async {
String? path = (await fetcher.readAsXmlOrNull("/META-INF/container.xml"))
?.firstElementChild
?.getElement("rootfiles", namespace: Namespaces.opc)
?.getElement("rootfile", namespace: Namespaces.opc)
?.getAttribute("full-path");
if (path == null) {
throw Exception("Unable to find an OPF file.");
}
return path;
}