public RingResponse ring()

in adapters/base/src/main/java/org/apache/cassandra/sidecar/adapters/base/RingProvider.java [67:124]
51 lines of code
3 McCabe index (conditional complexity)

    public RingResponse ring(@Nullable String keyspace) throws UnknownHostException
    {
        StorageJmxOperations storageOps = initializeStorageOps();
        EndpointSnitchJmxOperations epSnitchInfo = initializeEndpointProxy();

        // Collect required data from the probe
        List<String> liveNodes = storageOps.getLiveNodesWithPort();
        List<String> deadNodes = storageOps.getUnreachableNodesWithPort();
        Status status = new Status(liveNodes, deadNodes);
        List<String> joiningNodes = storageOps.getJoiningNodesWithPort();
        List<String> leavingNodes = storageOps.getLeavingNodesWithPort();
        List<String> movingNodes = storageOps.getMovingNodesWithPort();
        State state = new State(joiningNodes, leavingNodes, movingNodes);
        Map<String, String> loadMap = storageOps.getLoadMapWithPort();
        Map<String, String> tokensToEndpoints = storageOps.getTokenToEndpointWithPortMap();
        Map<String, String> endpointsToHostIds = storageOps.getEndpointWithPortToHostId();

        boolean showEffectiveOwnership = true;
        // Calculate per-token ownership of the ring
        Map<String, Float> ownerships;
        try
        {
            ownerships = storageOps.effectiveOwnershipWithPort(keyspace);
        }
        catch (IllegalStateException ex)
        {
            ownerships = storageOps.getOwnershipWithPort();
            LOGGER.warn("Unable to retrieve effective ownership information for keyspace={}", keyspace, ex);
            showEffectiveOwnership = false;
        }

        // DecimalFormat is not thread-safe, so we need to create a new instance per thread
        DecimalFormat ownsFormat = new DecimalFormat(DECIMAL_FORMAT);
        RingResponse response = new RingResponse(tokensToEndpoints.size());
        for (Map.Entry<String, String> entry : tokensToEndpoints.entrySet())
        {
            String endpoint = entry.getValue();
            String token = entry.getKey();
            HostAndPort hap = resolve(endpoint, dnsResolver);
            Float owns = ownerships.get(endpoint);
            RingEntry ringEntry = new RingEntry.Builder()
                                  .datacenter(epSnitchInfo.getDatacenter(endpoint))
                                  .rack(queryRack(epSnitchInfo, endpoint))
                                  .status(status.of(endpoint))
                                  .state(state.of(endpoint))
                                  .load(loadMap.getOrDefault(endpoint, UNKNOWN_SHORT))
                                  .owns(formatOwns(showEffectiveOwnership, ownsFormat, owns))
                                  .token(token)
                                  .address(hap.getHost())
                                  .port(hap.getPort())
                                  .fqdn(dnsResolver.reverseResolve(hap.getHost()))
                                  .hostId(endpointsToHostIds.getOrDefault(endpoint, UNKNOWN))
                                  .build();
            response.add(ringEntry);
        }

        return response;
    }