1 files changed, 249 insertions, 0 deletions
diff --git a/components/bbs-event-processor/src/main/java/org/onap/bbs/event/processor/pipelines/Scheduler.java b/components/bbs-event-processor/src/main/java/org/onap/bbs/event/processor/pipelines/Scheduler.java
new file mode 100644
index 00000000..64d212ad
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+++ b/components/bbs-event-processor/src/main/java/org/onap/bbs/event/processor/pipelines/Scheduler.java
@@ -0,0 +1,249 @@
+/*
+ * ============LICENSE_START=======================================================
+ * BBS-RELOCATION-CPE-AUTHENTICATION-HANDLER
+ * ================================================================================
+ * Copyright (C) 2019 NOKIA Intellectual Property. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.bbs.event.processor.pipelines;
+
+import java.time.Duration;
+import java.time.Instant;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ScheduledFuture;
+
+import javax.annotation.PostConstruct;
+import javax.annotation.PreDestroy;
+
+import org.onap.bbs.event.processor.config.ApplicationConfiguration;
+import org.onap.bbs.event.processor.config.ConfigurationChangeObserver;
+import org.onap.bbs.event.processor.config.ConsulConfigurationGateway;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.scheduling.TaskScheduler;
+import org.springframework.scheduling.annotation.EnableScheduling;
+
+@Configuration
+@EnableScheduling
+public class Scheduler implements ConfigurationChangeObserver {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(Scheduler.class);
+
+    private static final int PIPELINES_INITIAL_DELAY_IN_SECONDS = 10;
+    private static final int DEFAULT_PIPELINES_POLLING_INTERVAL = 15;
+    private static final Duration CBS_INITIAL_DELAY = Duration.ofSeconds(1);
+    private static final int DEFAULT_CBS_POLLING_INTERVAL = 30;
+
+    private final ConsulConfigurationGateway configurationGateway;
+    private final TaskScheduler taskScheduler;
+    private final ReRegistrationPipeline reRegistrationPipeline;
+    private final CpeAuthenticationPipeline cpeAuthenticationPipeline;
+    private ApplicationConfiguration configuration;
+    private Map<String, ScheduledFuture> processingScheduledTasks;
+    private ScheduledFuture cbsScheduledTask;
+    private int currentPipelinesPollingInterval;
+    private int currentCbsPollingInterval;
+
+    @Autowired
+    Scheduler(ApplicationConfiguration configuration,
+                     ConsulConfigurationGateway configurationGateway,
+                     TaskScheduler taskScheduler,
+                     ReRegistrationPipeline reRegistrationPipeline,
+                     CpeAuthenticationPipeline cpeAuthenticationPipeline) {
+        this.configuration = configuration;
+        this.configurationGateway = configurationGateway;
+        this.taskScheduler = taskScheduler;
+        this.reRegistrationPipeline = reRegistrationPipeline;
+        this.cpeAuthenticationPipeline = cpeAuthenticationPipeline;
+        processingScheduledTasks = new ConcurrentHashMap<>();
+    }
+
+    /**
+     * Sets up Scheduler.
+     *
+     * <p>Initiates CBS configuration fetch periodic task and DMaaP PNF re-registration and CPE
+     * authentication event polling tasks.</p>
+     *
+     * <p>It also registers for application configuration changes notifications.</p>
+     */
+    @PostConstruct
+    public void setupScheduler() {
+
+        // Initiate periodic configuration fetching from CBS
+        currentCbsPollingInterval = verifyCbsPollingInterval();
+        cbsScheduledTask =
+                taskScheduler.schedule(() -> configurationGateway.periodicallyFetchConfigFromCbs(CBS_INITIAL_DELAY,
+                Duration.ofSeconds(currentCbsPollingInterval)), Instant.now());
+
+        // Initiate Processing tasks
+        currentPipelinesPollingInterval = validatePipelinesPollingInterval();
+        LOGGER.info("BBS event processing pipelines will start in {} seconds "
+                + "and will run periodically every {} seconds", PIPELINES_INITIAL_DELAY_IN_SECONDS,
+                currentPipelinesPollingInterval);
+        Instant desiredStartTime = Instant.now().plusSeconds(PIPELINES_INITIAL_DELAY_IN_SECONDS);
+        scheduleProcessingTasks(desiredStartTime, currentPipelinesPollingInterval);
+
+        // Register for configuration changes
+        configuration.register(this);
+    }
+
+    /**
+     * Un-registers from getting application configuration changes notifications.
+     */
+    @PreDestroy
+    public void unRegisterAsConfigChangeObserver() {
+        configuration.unRegister(this);
+    }
+
+    @Override
+    public void updateConfiguration(ApplicationConfiguration newConfiguration) {
+        if (newConfiguration.getPipelinesPollingIntervalInSeconds() != currentPipelinesPollingInterval
+                || newConfiguration.getCbsPollingInterval() != currentCbsPollingInterval) {
+            configuration = newConfiguration;
+        }
+        if (newConfiguration.getPipelinesPollingIntervalInSeconds() != currentPipelinesPollingInterval) {
+            LOGGER.info("Pipelines Polling interval has changed. Re-scheduling processing pipelines");
+            cancelScheduledProcessingTasks();
+            reScheduleProcessingTasks();
+        }
+        int newCbsPollingInterval = newConfiguration.getCbsPollingInterval();
+        if (newCbsPollingInterval != currentCbsPollingInterval) {
+            if (newCbsPollingInterval < DEFAULT_CBS_POLLING_INTERVAL) {
+                LOGGER.warn("CBS Polling interval is too small ({}). Will not re-schedule CBS job",
+                        newCbsPollingInterval);
+            } else {
+                rescheduleCbsScheduledTask(newCbsPollingInterval);
+            }
+        }
+    }
+
+    private void rescheduleCbsScheduledTask(int newCbsPollingInterval) {
+        LOGGER.info("CBS Polling interval has changed. Re-scheduling CBS job");
+        currentCbsPollingInterval = newCbsPollingInterval;
+        if (!cbsScheduledTask.isDone()) {
+            if (cbsScheduledTask.cancel(true)) {
+                LOGGER.debug("CBS task has been cancelled");
+            } else {
+                LOGGER.error("Error while cancelling CBS task. Task status (isDone/isCanceled) is ({}/{})",
+                        cbsScheduledTask.isDone(), cbsScheduledTask.isCancelled());
+            }
+        }
+        cbsScheduledTask = taskScheduler.schedule(() ->
+                        configurationGateway.rescheduleCbsConfigurationRetrieval(CBS_INITIAL_DELAY,
+                Duration.ofSeconds(currentCbsPollingInterval)), Instant.now());
+    }
+
+    /**
+     * Cancels DMaaP polling tasks (PNF re-registration & CPE authentication).
+     * @return Tasks cancellation result
+     */
+    public boolean cancelScheduledProcessingTasks() {
+
+        if (processingScheduledTasks.isEmpty()) {
+            LOGGER.debug("No tasks found to cancel");
+            return true;
+        }
+
+        processingScheduledTasks.forEach((key, value) -> {
+            if (value.cancel(false)) {
+                LOGGER.debug("Task {} has been cancelled", key);
+            } else {
+                LOGGER.error("Error while cancelling task {}. Task status (isDone/isCanceled) is ({}/{})",
+                        key, value.isDone(), value.isCancelled());
+            }
+        });
+        processingScheduledTasks.entrySet().removeIf(entry -> entry.getValue().isCancelled());
+        LOGGER.info("All cancelled tasks have been removed");
+        return processingScheduledTasks.isEmpty();
+    }
+
+    /**
+     * Reschedules DMaaP polling tasks (PNF re-registration & CPE authentication).
+     * @return Tasks rescheduling result
+     */
+    public boolean reScheduleProcessingTasks() {
+
+        if (processingScheduledTasks.size() != 0) {
+            // If every task is cancelled, we can remove and re-schedule
+            if (processingScheduledTasks.entrySet().stream()
+                    .allMatch(e -> e.getValue().isCancelled())) {
+                processingScheduledTasks.clear();
+                LOGGER.debug("Old cancelled tasks have been removed");
+            } else {
+                LOGGER.error("Cannot reschedule. There are {} active tasks that must be first cancelled",
+                        processingScheduledTasks.entrySet().stream()
+                                .filter(e -> !e.getValue().isCancelled())
+                                .count()
+                );
+                return false;
+            }
+        }
+        currentPipelinesPollingInterval = validatePipelinesPollingInterval();
+        LOGGER.info("Reschedule tasks");
+        scheduleProcessingTasks(Instant.now(), currentPipelinesPollingInterval);
+        return true;
+    }
+
+    int numberOfTotalTasks() {
+        return processingScheduledTasks.size();
+    }
+
+    long numberOfActiveTasks() {
+        return processingScheduledTasks.entrySet().stream()
+                .filter(e -> (!e.getValue().isCancelled()))
+                .count();
+    }
+
+    long numberOfCancelledTasks() {
+        return processingScheduledTasks.entrySet().stream()
+                .filter(e -> (e.getValue().isCancelled()))
+                .count();
+    }
+
+    private void scheduleProcessingTasks(Instant desiredStartTime, int pollingInterval) {
+        processingScheduledTasks.put("Re-registration",
+                taskScheduler.scheduleAtFixedRate(reRegistrationPipeline::processPnfReRegistrationEvents,
+                        desiredStartTime, Duration.ofSeconds(pollingInterval)));
+        processingScheduledTasks.put("CPE Authentication",
+                taskScheduler.scheduleAtFixedRate(cpeAuthenticationPipeline::processPnfCpeAuthenticationEvents,
+                        desiredStartTime, Duration.ofSeconds(pollingInterval)));
+    }
+
+    private int validatePipelinesPollingInterval() {
+        int pipelinesPollingInterval = configuration.getPipelinesPollingIntervalInSeconds();
+        boolean isSmallInterval = pipelinesPollingInterval < DEFAULT_PIPELINES_POLLING_INTERVAL;
+        int verifiedInterval = isSmallInterval ? DEFAULT_PIPELINES_POLLING_INTERVAL : pipelinesPollingInterval;
+        if (isSmallInterval) {
+            LOGGER.warn("Pipelines Polling interval is too small ({}). Defaulting to {}", pipelinesPollingInterval,
+                    DEFAULT_PIPELINES_POLLING_INTERVAL);
+        }
+        return verifiedInterval;
+    }
+
+    private int verifyCbsPollingInterval() {
+        int cbsPollingInterval = configuration.getCbsPollingInterval();
+        boolean isSmallInterval = cbsPollingInterval < DEFAULT_CBS_POLLING_INTERVAL;
+        int verifiedInterval = isSmallInterval ? DEFAULT_CBS_POLLING_INTERVAL : cbsPollingInterval;
+        if (isSmallInterval) {
+            LOGGER.warn("CBS Polling interval is too small ({}). Defaulting to {}", cbsPollingInterval,
+                    DEFAULT_CBS_POLLING_INTERVAL);
+        }
+        return verifiedInterval;
+    }
+}