private K8sInfoRegistry()

in oap-server/analyzer/meter-analyzer/src/main/java/org/apache/skywalking/oap/meter/analyzer/k8s/K8sInfoRegistry.java [45:120]
72 lines of code
9 McCabe index (conditional complexity)

    private K8sInfoRegistry() {
        ipPodMap = CacheBuilder.newBuilder()
            .expireAfterWrite(Duration.ofMinutes(3))
            .build(CacheLoader.from(ip -> KubernetesPods.INSTANCE
                .findByIP(ip)
                .map(it -> ObjectID
                    .builder()
                    .name(it.getMetadata().getName())
                    .namespace(it.getMetadata().getNamespace())
                    .build())
                .orElse(ObjectID.EMPTY)));

        ipServiceMap = CacheBuilder.newBuilder()
            .expireAfterWrite(Duration.ofMinutes(3))
            .build(CacheLoader.from(ip -> KubernetesServices.INSTANCE
                .list()
                .stream()
                .filter(it -> it.getSpec() != null)
                .filter(it -> it.getStatus() != null)
                .filter(it -> it.getMetadata() != null)
                .filter(it -> (it.getSpec().getClusterIPs() != null &&
                    it.getSpec().getClusterIPs().stream()
                        .anyMatch(clusterIP -> Objects.equals(clusterIP, ip)))
                    || (it.getStatus().getLoadBalancer() != null &&
                        it.getStatus().getLoadBalancer().getIngress() != null &&
                        it.getStatus().getLoadBalancer().getIngress().stream()
                            .anyMatch(ingress -> Objects.equals(ingress.getIp(), ip))))
                .map(it -> ObjectID
                    .builder()
                    .name(it.getMetadata().getName())
                    .namespace(it.getMetadata().getNamespace())
                    .build())
                .findFirst()
                .orElse(ObjectID.EMPTY)));

        podServiceMap = CacheBuilder.newBuilder()
            .expireAfterWrite(Duration.ofMinutes(3))
            .build(CacheLoader.from(podObjectID -> {
                final Optional<Pod> pod = KubernetesPods.INSTANCE
                    .findByObjectID(
                        ObjectID
                            .builder()
                            .name(podObjectID.name())
                            .namespace(podObjectID.namespace())
                            .build());

                if (!pod.isPresent()
                    || pod.get().getMetadata() == null
                    || pod.get().getMetadata().getLabels() == null) {
                    return ObjectID.EMPTY;
                }

                final Optional<Service> service = KubernetesServices.INSTANCE
                    .list()
                    .stream()
                    .filter(it -> it.getMetadata() != null)
                    .filter(it -> Objects.equals(it.getMetadata().getNamespace(), pod.get().getMetadata().getNamespace()))
                    .filter(it -> it.getSpec() != null)
                    .filter(it -> requireNonNull(it.getSpec()).getSelector() != null)
                    .filter(it -> !it.getSpec().getSelector().isEmpty())
                    .filter(it -> {
                        final Map<String, String> labels = pod.get().getMetadata().getLabels();
                        final Map<String, String> selector = it.getSpec().getSelector();
                        return hasIntersection(selector.entrySet(), labels.entrySet());
                    })
                    .findFirst();
                if (!service.isPresent()) {
                    return ObjectID.EMPTY;
                }
                return ObjectID
                    .builder()
                    .name(service.get().getMetadata().getName())
                    .namespace(service.get().getMetadata().getNamespace())
                    .build();
            }));
    }