ONOS-3763 Change flow state to PENDING_ADD when retrying

Will emit a RULE_UPDATE event if the state is changed.
Update unit test accordingly.

Change-Id: Ie84778c62f52f15b7636d41db246814145e73f77

@@ -97,6 +97,16 @@ public interface FlowRuleStore extends Store<FlowRuleBatchEvent, FlowRuleStoreDe
     FlowRuleEvent removeFlowRule(FlowEntry rule);
 
     /**
+     * Marks a flow rule as PENDING_ADD during retry.
+     *
+     * Emits flow_update event if the state is changed
+     *
+     * @param rule the flow rule that is retrying
+     * @return flow_updated event, or null if nothing updated
+     */
+    FlowRuleEvent pendingFlowRule(FlowEntry rule);
+
+    /**
      * Updates the flow table statistics of the specified device using
      * the given statistics.
      *

@@ -258,6 +258,23 @@ public class SimpleFlowRuleStore
     }
 
     @Override
+    public FlowRuleEvent pendingFlowRule(FlowEntry rule) {
+        List<StoredFlowEntry> entries = getFlowEntries(rule.deviceId(), rule.id());
+        synchronized (entries) {
+            for (StoredFlowEntry entry : entries) {
+                if (entry.equals(rule) &&
+                        entry.state() != FlowEntryState.PENDING_ADD) {
+                    synchronized (entry) {
+                        entry.setState(FlowEntryState.PENDING_ADD);
+                        return new FlowRuleEvent(Type.RULE_UPDATED, rule);
+                    }
+                }
+            }
+        }
+        return null;
+    }
+
+    @Override
     public void storeBatch(
             FlowRuleBatchOperation operation) {
         List<FlowRuleBatchEntry> toAdd = new ArrayList<>();

@@ -305,6 +305,7 @@ public class FlowRuleManager
                     break;
                 case ADDED:
                 case PENDING_ADD:
+                    event = store.pendingFlowRule(flowRule);
                     try {
                         frp.applyFlowRule(flowRule);
                     } catch (UnsupportedOperationException e) {

@@ -206,7 +206,7 @@ public class FlowRuleManagerTest {
         assertEquals("should still be 2 rules", 2, flowCount());
 
         providerService.pushFlowMetrics(DID, ImmutableList.of(fe1));
-        validateEvents(RULE_UPDATED);
+        validateEvents(RULE_UPDATED, RULE_UPDATED);
     }
 
     private boolean validateState(Map<FlowRule, FlowEntryState> expected) {
@@ -293,7 +293,7 @@ public class FlowRuleManagerTest {
         service.applyFlowRules(f3);
 
         providerService.pushFlowMetrics(DID, Collections.singletonList(fe3));
-        validateEvents(RULE_ADD_REQUESTED, RULE_ADDED);
+        validateEvents(RULE_ADD_REQUESTED, RULE_ADDED, RULE_UPDATED);
 
         providerService.flowRemoved(fe3);
         validateEvents();

@@ -526,6 +526,19 @@ public class NewDistributedFlowRuleStore
     }
 
     @Override
+    public FlowRuleEvent pendingFlowRule(FlowEntry rule) {
+        if (mastershipService.isLocalMaster(rule.deviceId())) {
+            StoredFlowEntry stored = flowTable.getFlowEntry(rule);
+            if (stored != null &&
+                    stored.state() != FlowEntryState.PENDING_ADD) {
+                stored.setState(FlowEntryState.PENDING_ADD);
+                return new FlowRuleEvent(Type.RULE_UPDATED, rule);
+            }
+        }
+        return null;
+    }
+
+    @Override
     public FlowRuleEvent addOrUpdateFlowRule(FlowEntry rule) {
         NodeId master = mastershipService.getMasterFor(rule.deviceId());
         if (Objects.equals(local, master)) {