private void start()

in src/main/java/org/opensearch/performanceanalyzer/rca/RcaController.java [197:283]
74 lines of code
6 McCabe index (conditional complexity)

    private void start() {
        try {
            Objects.requireNonNull(subscriptionManager);
            Objects.requireNonNull(rcaConf);
            if (dbProvider == null) {
                return;
            }

            subscriptionManager.setCurrentLocus(rcaConf.getTagMap().get("locus"));
            this.connectedComponents = getRcaGraphComponents(rcaConf);

            // Mute the rca nodes after the graph creation and before the scheduler start
            readAndUpdateMutedComponentsDuringStart();

            ThresholdMain thresholdMain = new ThresholdMain(RcaConsts.THRESHOLDS_PATH, rcaConf);
            persistenceProvider = PersistenceFactory.create(rcaConf);
            networkThreadPoolReference.set(
                    RcaControllerHelper.buildNetworkThreadPool(rcaConf.getNetworkQueueLength()));
            addRcaRequestHandler();
            queryRcaRequestHandler.setPersistable(persistenceProvider);
            addActionsRequestHandler();
            queryActionRequestHandler.setPersistable(persistenceProvider);
            receivedFlowUnitStore = new ReceivedFlowUnitStore(rcaConf.getPerVertexBufferLength());
            WireHopper net =
                    new WireHopper(
                            nodeStateManager,
                            rcaNetClient,
                            subscriptionManager,
                            networkThreadPoolReference,
                            receivedFlowUnitStore,
                            appContext);

            // RcaScheduler should be started with a snapshot of the AppContext as RcaController
            // monitors it for stale state and always restarts the scheduler if it finds its state
            // stale.
            AppContext copyAppContext = new AppContext(this.appContext);

            this.rcaScheduler =
                    new RCAScheduler(
                            connectedComponents,
                            dbProvider,
                            rcaConf,
                            thresholdMain,
                            persistenceProvider,
                            net,
                            copyAppContext);

            rcaNetServer.setSendDataHandler(
                    new PublishRequestHandler(
                            nodeStateManager, receivedFlowUnitStore, networkThreadPoolReference));
            rcaNetServer.setSubscribeHandler(
                    new SubscribeServerHandler(subscriptionManager, networkThreadPoolReference));

            Thread rcaSchedulerThread =
                    threadProvider.createThreadForRunnable(
                            () -> rcaScheduler.start(),
                            PerformanceAnalyzerThreads.RCA_SCHEDULER,
                            copyAppContext.getMyInstanceDetails().getInstanceId().toString());

            CountDownLatch schedulerStartLatch = new CountDownLatch(1);
            rcaScheduler.setSchedulerTrackingLatch(schedulerStartLatch);
            rcaSchedulerThread.start();
            if (!schedulerStartLatch.await(WAIT_FOR_SCHED_START_SECS, TimeUnit.SECONDS)) {
                LOG.error("Failed to start RcaScheduler.");
                throw new IllegalStateException(
                        "Failed to start RcaScheduler within "
                                + WAIT_FOR_SCHED_START_SECS
                                + " seconds.");
            }

            if (rcaScheduler.getState() != RcaSchedulerState.STATE_STARTED) {
                LOG.error(
                        "RCA scheduler didn't start within {} seconds", WAIT_FOR_SCHED_START_SECS);
            }
        } catch (ClassNotFoundException
                | NoSuchMethodException
                | InvocationTargetException
                | InstantiationException
                | IllegalAccessException
                | MalformedConfig
                | SQLException
                | IOException e) {
            LOG.error("Couldn't build connected components or persistable..", e);
        } catch (Exception ex) {
            LOG.error("Couldn't start RcaController", ex);
        }
    }