Implement security group manager, codec and watcher with unit tests

Change-Id: Ib2201d140b9dcb2eff453f13447113bdba66babd
diff --git a/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/impl/KubevirtSecurityGroupWatcher.java b/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/impl/KubevirtSecurityGroupWatcher.java
new file mode 100644
index 0000000..2fb53a9
--- /dev/null
+++ b/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/impl/KubevirtSecurityGroupWatcher.java
@@ -0,0 +1,364 @@
+/*
+ * Copyright 2021-present Open Networking Foundation
+ *
+ * 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.
+ */
+package org.onosproject.kubevirtnetworking.impl;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import io.fabric8.kubernetes.client.KubernetesClient;
+import io.fabric8.kubernetes.client.Watcher;
+import io.fabric8.kubernetes.client.WatcherException;
+import io.fabric8.kubernetes.client.dsl.base.CustomResourceDefinitionContext;
+import org.onosproject.cluster.ClusterService;
+import org.onosproject.cluster.LeadershipService;
+import org.onosproject.cluster.NodeId;
+import org.onosproject.core.ApplicationId;
+import org.onosproject.core.CoreService;
+import org.onosproject.kubevirtnetworking.api.AbstractWatcher;
+import org.onosproject.kubevirtnetworking.api.KubevirtSecurityGroup;
+import org.onosproject.kubevirtnetworking.api.KubevirtSecurityGroupAdminService;
+import org.onosproject.kubevirtnetworking.api.KubevirtSecurityGroupRule;
+import org.onosproject.kubevirtnode.api.KubevirtApiConfigEvent;
+import org.onosproject.kubevirtnode.api.KubevirtApiConfigListener;
+import org.onosproject.kubevirtnode.api.KubevirtApiConfigService;
+import org.onosproject.mastership.MastershipService;
+import org.osgi.service.component.annotations.Activate;
+import org.osgi.service.component.annotations.Component;
+import org.osgi.service.component.annotations.Deactivate;
+import org.osgi.service.component.annotations.Reference;
+import org.osgi.service.component.annotations.ReferenceCardinality;
+import org.slf4j.Logger;
+
+import java.io.IOException;
+import java.util.Objects;
+import java.util.concurrent.ExecutorService;
+
+import static java.util.concurrent.Executors.newSingleThreadExecutor;
+import static org.onlab.util.Tools.groupedThreads;
+import static org.onosproject.kubevirtnetworking.api.Constants.KUBEVIRT_NETWORKING_APP_ID;
+import static org.onosproject.kubevirtnetworking.util.KubevirtNetworkingUtil.k8sClient;
+import static org.slf4j.LoggerFactory.getLogger;
+
+/**
+ * Kubevirt security group watcher used for feeding kubevirt security group information.
+ */
+@Component(immediate = true)
+public class KubevirtSecurityGroupWatcher extends AbstractWatcher {
+
+    private final Logger log = getLogger(getClass());
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected CoreService coreService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected MastershipService mastershipService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected ClusterService clusterService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected LeadershipService leadershipService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected KubevirtSecurityGroupAdminService adminService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected KubevirtApiConfigService configService;
+
+    private final ExecutorService eventExecutor = newSingleThreadExecutor(
+            groupedThreads(this.getClass().getSimpleName(), "event-handler"));
+
+    private final InternalSecurityGroupWatcher
+            sgWatcher = new InternalSecurityGroupWatcher();
+    private final InternalSecurityGroupRuleWatcher
+            sgrWatcher = new InternalSecurityGroupRuleWatcher();
+    private final InternalKubevirtApiConfigListener
+            configListener = new InternalKubevirtApiConfigListener();
+
+    CustomResourceDefinitionContext securityGroupCrdCxt = new CustomResourceDefinitionContext
+            .Builder()
+            .withGroup("kubevirt.io")
+            .withScope("Cluster")
+            .withVersion("v1")
+            .withPlural("securitygroups")
+            .build();
+
+    CustomResourceDefinitionContext securityGroupRuleCrdCxt = new CustomResourceDefinitionContext
+            .Builder()
+            .withGroup("kubevirt.io")
+            .withScope("Cluster")
+            .withVersion("v1")
+            .withPlural("securitygrouprules")
+            .build();
+
+    private ApplicationId appId;
+    private NodeId localNodeId;
+
+    @Activate
+    protected void activate() {
+        appId = coreService.registerApplication(KUBEVIRT_NETWORKING_APP_ID);
+        localNodeId = clusterService.getLocalNode().id();
+        leadershipService.runForLeadership(appId.name());
+        configService.addListener(configListener);
+
+        log.info("Started");
+    }
+
+    @Deactivate
+    protected void deactivate() {
+        configService.removeListener(configListener);
+        leadershipService.withdraw(appId.name());
+        eventExecutor.shutdown();
+
+        log.info("Stopped");
+    }
+
+    private void instantiateSgWatcher() {
+        KubernetesClient client = k8sClient(configService);
+
+        if (client != null) {
+            try {
+                client.customResource(securityGroupCrdCxt).watch(sgWatcher);
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+        }
+    }
+
+    private void instantiateSgrWatcher() {
+        KubernetesClient client = k8sClient(configService);
+
+        if (client != null) {
+            try {
+                client.customResource(securityGroupRuleCrdCxt).watch(sgrWatcher);
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+        }
+    }
+
+    private KubevirtSecurityGroup parseSecurityGroup(String resource) {
+        try {
+            ObjectMapper mapper = new ObjectMapper();
+            JsonNode json = mapper.readTree(resource);
+            ObjectNode spec = (ObjectNode) json.get("spec");
+            return codec(KubevirtSecurityGroup.class).decode(spec, this);
+        } catch (IOException e) {
+            log.error("Failed to parse kubevirt security group object");
+        }
+
+        return null;
+    }
+
+    private KubevirtSecurityGroupRule parseSecurityGroupRule(String resource) {
+        try {
+            ObjectMapper mapper = new ObjectMapper();
+            JsonNode json = mapper.readTree(resource);
+            ObjectNode spec = (ObjectNode) json.get("spec");
+            return codec(KubevirtSecurityGroupRule.class).decode(spec, this);
+        } catch (IOException e) {
+            log.error("Failed to parse kubevirt security group rule object");
+        }
+
+        return null;
+    }
+
+    private class InternalKubevirtApiConfigListener implements KubevirtApiConfigListener {
+
+        private boolean isRelevantHelper() {
+            return Objects.equals(localNodeId, leadershipService.getLeader(appId.name()));
+        }
+
+        @Override
+        public void event(KubevirtApiConfigEvent event) {
+
+            switch (event.type()) {
+                case KUBEVIRT_API_CONFIG_UPDATED:
+                    eventExecutor.execute(this::processConfigUpdate);
+                    break;
+                case KUBEVIRT_API_CONFIG_CREATED:
+                case KUBEVIRT_API_CONFIG_REMOVED:
+                default:
+                    // do nothing
+                    break;
+            }
+        }
+
+        private void processConfigUpdate() {
+            if (!isRelevantHelper()) {
+                return;
+            }
+
+            instantiateSgWatcher();
+            instantiateSgrWatcher();
+        }
+    }
+
+    private class InternalSecurityGroupWatcher implements Watcher<String> {
+
+        @Override
+        public void eventReceived(Action action, String resource) {
+            switch (action) {
+                case ADDED:
+                    eventExecutor.execute(() -> processAddition(resource));
+                    break;
+                case MODIFIED:
+                    eventExecutor.execute(() -> processModification(resource));
+                    break;
+                case DELETED:
+                    eventExecutor.execute(() -> processDeletion(resource));
+                    break;
+                default:
+                    // do nothing
+                    break;
+            }
+        }
+
+        @Override
+        public void onClose(WatcherException e) {
+            // due to the bugs in fabric8, the watcher might be closed,
+            // we will re-instantiate the watcher in this case
+            // FIXME: https://github.com/fabric8io/kubernetes-client/issues/2135
+            log.warn("Security Group watcher OnClose, re-instantiate the watcher...");
+
+            instantiateSgWatcher();
+        }
+
+        private void processAddition(String resource) {
+            if (!isMaster()) {
+                return;
+            }
+
+            KubevirtSecurityGroup sg = parseSecurityGroup(resource);
+
+            if (sg != null) {
+                log.trace("Process Security Group {} creating event from API server.", sg.name());
+
+                if (adminService.securityGroup(sg.id()) == null) {
+                    adminService.createSecurityGroup(sg);
+                }
+            }
+        }
+
+        private void processModification(String resource) {
+            if (!isMaster()) {
+                return;
+            }
+
+            KubevirtSecurityGroup sg = parseSecurityGroup(resource);
+
+            if (sg != null) {
+                log.trace("Process Security Group {} updating event from API server.", sg.name());
+
+                // since Security Group CRD does not contains any rules information,
+                // we need to manually add all rules from original to the updated one
+                KubevirtSecurityGroup orig = adminService.securityGroup(sg.id());
+                if (orig != null) {
+                    KubevirtSecurityGroup updated = sg.updateRules(orig.rules());
+                    adminService.updateSecurityGroup(updated);
+                }
+            }
+        }
+
+        private void processDeletion(String resource) {
+            if (!isMaster()) {
+                return;
+            }
+
+            KubevirtSecurityGroup sg = parseSecurityGroup(resource);
+
+            if (sg != null) {
+                log.trace("Process Security Group {} removal event from API server.", sg.name());
+
+                adminService.removeSecurityGroup(sg.id());
+            }
+        }
+    }
+
+    private class InternalSecurityGroupRuleWatcher implements Watcher<String> {
+
+        @Override
+        public void eventReceived(Action action, String resource) {
+            switch (action) {
+                case ADDED:
+                    eventExecutor.execute(() -> processAddition(resource));
+                    break;
+                case MODIFIED:
+                    eventExecutor.execute(() -> processModification(resource));
+                    break;
+                case DELETED:
+                    eventExecutor.execute(() -> processDeletion(resource));
+                    break;
+                default:
+                    // do nothing
+                    break;
+            }
+        }
+
+        @Override
+        public void onClose(WatcherException e) {
+            // due to the bugs in fabric8, the watcher might be closed,
+            // we will re-instantiate the watcher in this case
+            // FIXME: https://github.com/fabric8io/kubernetes-client/issues/2135
+            log.warn("Security Group Rule watcher OnClose, re-instantiate the watcher...");
+
+            instantiateSgrWatcher();
+        }
+
+        private void processAddition(String resource) {
+            if (!isMaster()) {
+                return;
+            }
+
+            KubevirtSecurityGroupRule sgr = parseSecurityGroupRule(resource);
+
+            if (sgr != null) {
+                log.trace("Process Security Group Rule {} creating event from API server.", sgr.id());
+
+                if (adminService.securityGroupRule(sgr.id()) == null) {
+                    adminService.createSecurityGroupRule(sgr);
+                }
+            }
+        }
+
+        private void processModification(String resource) {
+            if (!isMaster()) {
+                return;
+            }
+
+            // we do not handle the update case, as we assume the security group rule
+            // object is immutable
+        }
+
+        private void processDeletion(String resource) {
+            if (!isMaster()) {
+                return;
+            }
+
+            KubevirtSecurityGroupRule sgr = parseSecurityGroupRule(resource);
+
+            if (sgr != null) {
+                log.trace("Process Security Group Rule {} removal event from API server.", sgr.id());
+
+                adminService.removeSecurityGroupRule(sgr.id());
+            }
+        }
+    }
+
+    private boolean isMaster() {
+        return Objects.equals(localNodeId, leadershipService.getLeader(appId.name()));
+    }
+}