multi event support for a worklet in workflow app

Change-Id: I3178110da75b26f96f8889acc0dd2c715fc567ec
diff --git a/apps/workflow/app/src/main/java/org/onosproject/workflow/impl/DistributedContextEventMapTreeStore.java b/apps/workflow/app/src/main/java/org/onosproject/workflow/impl/DistributedContextEventMapTreeStore.java
index 1b725de..8cd352e 100644
--- a/apps/workflow/app/src/main/java/org/onosproject/workflow/impl/DistributedContextEventMapTreeStore.java
+++ b/apps/workflow/app/src/main/java/org/onosproject/workflow/impl/DistributedContextEventMapTreeStore.java
@@ -19,6 +19,8 @@
 import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
+import org.onosproject.store.service.EventuallyConsistentMap;
+import org.onosproject.store.service.WallClockTimestamp;
 import org.osgi.service.component.annotations.Activate;
 import org.osgi.service.component.annotations.Component;
 import org.osgi.service.component.annotations.Deactivate;
@@ -43,6 +45,7 @@
 import java.util.Map;
 import java.util.Objects;
 import java.util.Optional;
+import java.util.Set;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ExecutionException;
 
@@ -63,6 +66,9 @@
 
     private AsyncDocumentTree<String> eventMapTree;
 
+    private EventuallyConsistentMap<String, Set<String>> hintSetPerCxtMap;
+
+
     @Activate
     public void activate() {
 
@@ -78,36 +84,66 @@
                 .withName("context-event-map-store")
                 .withOrdering(Ordering.INSERTION)
                 .buildDocumentTree();
+
+        hintSetPerCxtMap = storageService.<String, Set<String>>eventuallyConsistentMapBuilder()
+                .withName("workflow-event-hint-per-cxt")
+                .withSerializer(eventMapNamespace)
+                .withTimestampProvider((k, v) -> new WallClockTimestamp())
+                .build();
+
         log.info("Started");
     }
 
     @Deactivate
     public void deactivate() {
         eventMapTree.destroy();
+        hintSetPerCxtMap.destroy();
         log.info("Stopped");
     }
 
     @Override
-    public void registerEventMap(String eventType, String eventHint,
+    public void registerEventMap(String eventType, Set<String> eventHintSet,
                                  String contextName, String programCounterString) throws WorkflowException {
-        DocumentPath dpath = DocumentPath.from(Lists.newArrayList("root", eventType, eventHint, contextName));
-        String currentWorkletType = completeVersioned(eventMapTree.get(dpath));
-        if (currentWorkletType == null) {
-            complete(eventMapTree.createRecursive(dpath, programCounterString));
-        } else {
-            complete(eventMapTree.replace(dpath, programCounterString, currentWorkletType));
+        for (String eventHint : eventHintSet) {
+            //Insert in eventCxtPerHintMap
+            DocumentPath dpathForCxt = DocumentPath.from(Lists.newArrayList(
+                    "root", eventType, eventHint, contextName));
+            String currentWorkletType = completeVersioned(eventMapTree.get(dpathForCxt));
+            if (currentWorkletType == null) {
+                complete(eventMapTree.createRecursive(dpathForCxt, programCounterString));
+            } else {
+                complete(eventMapTree.replace(dpathForCxt, programCounterString, currentWorkletType));
+            }
+            log.trace("RegisterEventMap for eventType:{}, eventSet:{}, contextName:{}, pc:{}",
+                     eventType, eventHintSet, contextName, programCounterString);
+
         }
+        hintSetPerCxtMap.put(contextName, eventHintSet);
+        log.trace("RegisterEventMap in hintSetPerCxt for " +
+                         "eventType:{}, eventSet:{}, contextName:{}, pc:{}",
+                 eventType, eventHintSet, contextName, programCounterString);
     }
 
     @Override
-    public void unregisterEventMap(String eventType, String eventHint, String contextName) throws WorkflowException {
-        DocumentPath contextPath = DocumentPath.from(Lists.newArrayList("root", eventType, eventHint, contextName));
-        complete(eventMapTree.removeNode(contextPath));
+    public void unregisterEventMap(String eventType, String contextName)
+            throws WorkflowException {
+
+        Set<String> hints = hintSetPerCxtMap.get(contextName);
+        for (String eventHint : hints) {
+            //Remove from eventCxtPerHintMap
+            complete(eventMapTree.removeNode(DocumentPath.from(Lists.newArrayList(
+                    "root", eventType, eventHint, contextName))));
+            log.trace("UnregisterEventMap from eventCxtPerHintMap for eventType:{}, eventSet:{}, contextName:{}",
+                     eventType, eventHint, contextName);
+        }
+        hintSetPerCxtMap.remove(contextName);
     }
 
+
     @Override
-    public Map<String, String> getEventMap(String eventType, String eventHint) throws WorkflowException {
-        DocumentPath path = DocumentPath.from(Lists.newArrayList("root", eventType, eventHint));
+    public Map<String, String> getEventMapByHint(String eventType, String eventHint) throws WorkflowException {
+        DocumentPath path = DocumentPath.from(
+                Lists.newArrayList("root", eventType, eventHint));
         Map<String, Versioned<String>> contexts = complete(eventMapTree.getChildren(path));
         Map<String, String> eventMap = Maps.newHashMap();
         if (Objects.isNull(contexts)) {
@@ -117,10 +153,25 @@
         for (Map.Entry<String, Versioned<String>> entry : contexts.entrySet()) {
             eventMap.put(entry.getKey(), entry.getValue().value());
         }
+        log.trace("getEventMapByHint returns eventMap {} ", eventMap);
         return eventMap;
     }
 
     @Override
+    public boolean isEventMapPresent(String contextName) {
+        Map<String, String> eventMap = Maps.newHashMap();
+        Set<String> eventHintSet = hintSetPerCxtMap.get(contextName);
+        if (Objects.nonNull(eventHintSet)) {
+            log.trace("EventMap present for Context:{}", contextName);
+            return true;
+        } else {
+            log.trace("EventMap Doesnt exist for Context:{}", contextName);
+            return false;
+        }
+    }
+
+
+    @Override
     public Map<String, Versioned<String>> getChildren(String path) throws WorkflowException {
         DocumentPath dpath = DocumentPath.from(path);
         Map<String, Versioned<String>> entries = complete(eventMapTree.getChildren(dpath));
diff --git a/apps/workflow/app/src/main/java/org/onosproject/workflow/impl/WorkFlowEngine.java b/apps/workflow/app/src/main/java/org/onosproject/workflow/impl/WorkFlowEngine.java
index 237f70e..b472c5f 100644
--- a/apps/workflow/app/src/main/java/org/onosproject/workflow/impl/WorkFlowEngine.java
+++ b/apps/workflow/app/src/main/java/org/onosproject/workflow/impl/WorkFlowEngine.java
@@ -16,7 +16,6 @@
 package org.onosproject.workflow.impl;
 
 import com.fasterxml.jackson.databind.node.JsonNodeFactory;
-import com.google.common.collect.Lists;
 import org.onosproject.cluster.ClusterService;
 import org.onosproject.cluster.LeadershipService;
 import org.onosproject.cluster.NodeId;
@@ -64,6 +63,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
+import java.util.Set;
 import java.util.UUID;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ExecutorService;
@@ -242,7 +242,7 @@
         }
 
         try {
-            eventMap = eventMapStore.getEventMap(event.getClass().getName(), eventHint);
+            eventMap = eventMapStore.getEventMapByHint(event.getClass().getName(), eventHint);
         } catch (WorkflowException e) {
             log.error("Exception: ", e);
             return;
@@ -290,22 +290,25 @@
     }
 
     @Override
-    public void registerEventMap(Class<? extends Event> eventType, String eventHint,
+    public void registerEventMap(Class<? extends Event> eventType, Set<String> eventHintSet,
                                  String contextName, String programCounterString) throws WorkflowException {
-        eventMapStore.registerEventMap(eventType.getName(), eventHint, contextName, programCounterString);
-        for (int i = 0; i < MAX_REGISTER_EVENTMAP_WAITS; i++) {
-            Map<String, String> eventMap = eventMapStore.getEventMap(eventType.getName(), eventHint);
-            if (eventMap != null && eventMap.containsKey(contextName)) {
-                return;
-            }
-            try {
-                log.info("sleep {}", i);
-                Thread.sleep(10L * (i + 1));
-            } catch (InterruptedException e) {
-                log.error("Exception: ", e);
-                Thread.currentThread().interrupt();
+        eventMapStore.registerEventMap(eventType.getName(), eventHintSet, contextName, programCounterString);
+        for (String eventHint : eventHintSet) {
+            for (int i = 0; i < MAX_REGISTER_EVENTMAP_WAITS; i++) {
+                Map<String, String> eventMap = eventMapStore.getEventMapByHint(eventType.getName(), eventHint);
+                if (eventMap != null && eventMap.containsKey(contextName)) {
+                    break;
+                }
+                try {
+                    log.info("sleep {}", i);
+                    Thread.sleep(10L * (i + 1));
+                } catch (InterruptedException e) {
+                    log.error("Exception: ", e);
+                    Thread.currentThread().interrupt();
+                }
             }
         }
+
     }
 
     @Override
@@ -442,19 +445,8 @@
      */
     private EventTask execEventTask(EventTask task) {
 
-        Map<String, String> eventMap = null;
-        try {
-            eventMap = eventMapStore.getEventMap(task.event().getClass().getName(), task.eventHint());
-        } catch (WorkflowException e) {
-            log.error("Exception: {}, trace: {}", e, Lists.newArrayList(e.getStackTrace()));
-            return task;
-        }
-
-        if (Objects.isNull(eventMap) || eventMap.isEmpty()) {
-            return task;
-        }
-
-        if (Objects.isNull(eventMap.get(task.context().name()))) {
+        if (!eventMapStore.isEventMapPresent(task.context().name())) {
+            log.trace("EventMap doesnt exist for taskcontext:{}", task.context().name());
             return task;
         }
 
@@ -501,10 +493,10 @@
                 log.trace("{} task:{}, context: {}", latestContext.name(), task, latestContext);
 
                 eventMapStore.unregisterEventMap(
-                        task.eventType(), task.eventHint(), latestContext.name());
+                        task.eventType(), latestContext.name());
 
                 //completed case
-                // increase program counter
+                //increase program counter
                 ProgramCounter pc = latestContext.current();
                 latestContext.setCurrent(workflow.increased(pc));
 
@@ -543,20 +535,8 @@
      */
     private HandlerTask execEventTimeoutTask(EventTimeoutTask task) {
 
-        Map<String, String> eventMap = null;
-        try {
-            eventMap = eventMapStore.getEventMap(task.eventType(), task.eventHint());
-        } catch (WorkflowException e) {
-            log.error("execEventTimeoutTask: Exception: {}, trace: {}",
-                    e, Lists.newArrayList(e.getStackTrace()));
-            return task;
-        }
-
-        if (Objects.isNull(eventMap) || eventMap.isEmpty()) {
-            return task;
-        }
-
-        if (Objects.isNull(eventMap.get(task.context().name()))) {
+        if (!eventMapStore.isEventMapPresent(task.context().name())) {
+            log.trace("EventMap doesnt exist for taskcontext:{}", task.context().name());
             return task;
         }
 
@@ -590,8 +570,7 @@
 
             initWorkletExecution(latestContext);
 
-            eventMapStore.unregisterEventMap(
-                    task.eventType(), task.eventHint(), latestContext.name());
+            eventMapStore.unregisterEventMap(task.eventType(), latestContext.name());
 
             log.info("{} worklet.timeout(for event):{}", latestContext.name(), worklet.tag());
             log.trace("{} task:{}, context: {}", latestContext.name(), task, latestContext);
@@ -796,7 +775,7 @@
                     throw new WorkflowException(msg);
                 }
 
-                registerEventMap(latestContext.completionEventType(), latestContext.completionEventHint(),
+                registerEventMap(latestContext.completionEventType(), latestContext.completionEventHints(),
                         latestContext.name(), pc.toString());
 
                 latestContext.completionEventGenerator().apply();
@@ -806,7 +785,7 @@
                             .context(latestContext)
                             .programCounter(pc)
                             .eventType(latestContext.completionEventType().getName())
-                            .eventHint(latestContext.completionEventHint())
+                            .eventHintSet(latestContext.completionEventHints())
                             .build();
                     timerChain.schedule(latestContext.completionEventTimeout(),
                             () -> {