@Override
    public Collection<RegisteredService> load() {
        val references = firestore.collection(collectionName).listDocuments();
        return StreamSupport.stream(references.spliterator(), false)
            .map(doc -> FunctionUtils.doUnchecked(() -> doc.get().get()))
            .map(doc -> doc.getString("json"))
            .filter(Objects::nonNull)
            .map(serializer::from)
            .collect(Collectors.toSet());
    }
This is {@link GoogleCloudFirestoreServiceRegistry}.

@author Misagh Moayyed
@since 7.0.0
support/cas-server-support-gcp-firestore-service-registry/src/main/java/org/apereo/cas/services/GoogleCloudFirestoreServiceRegistry.java