in invoker/core/src/main/java/com/google/cloud/functions/invoker/GcfEvents.java [198:206]
SourceAndSubject convertResourceToSourceAndSubject(String resourceName, Event legacyEvent) {
Matcher matcher = STORAGE_RESOURCE_PATTERN.matcher(resourceName);
if (matcher.matches()) {
String resource = matcher.group(1);
String subject = matcher.group(2);
return SourceAndSubject.of(resource, subject);
}
return super.convertResourceToSourceAndSubject(resourceName, legacyEvent);
}