In this commit:

    Removing dependence on hashing for unique groupkeys in ofdpa driver.
    Group-store no longer removes groups from store if a group-operation fails due to GROUP_EXISTS.
    Group-store also checks for unique group-id when given by app.
    Group-provider now logs warning before making call to core.

Change-Id: I4a1dcb887cb74cd6e245df0c82c90a50d8f3898a

@@ -537,6 +537,19 @@ public class DistributedGroupStore
             // Get a new group identifier
             id = new DefaultGroupId(getFreeGroupIdValue(groupDesc.deviceId()));
         } else {
+            // we need to use the identifier passed in by caller, but check if
+            // already used
+            Group existing = getGroup(groupDesc.deviceId(),
+                                      new DefaultGroupId(groupDesc.givenGroupId()));
+            if (existing != null) {
+                log.warn("Group already exists with the same id: 0x{} in dev:{} "
+                        + "but with different key: {} (request gkey: {})",
+                        Integer.toHexString(groupDesc.givenGroupId()),
+                        groupDesc.deviceId(),
+                        existing.appCookie(),
+                        groupDesc.appCookie());
+                return;
+            }
             id = new DefaultGroupId(groupDesc.givenGroupId());
         }
         // Create a group entry object
@@ -621,7 +634,8 @@ public class DistributedGroupStore
         // Check if a group is existing with the provided key
         Group oldGroup = getGroup(deviceId, oldAppCookie);
         if (oldGroup == null) {
-            log.warn("updateGroupDescriptionInternal: Group not found...strange");
+            log.warn("updateGroupDescriptionInternal: Group not found...strange. "
+                    + "GroupKey:{} DeviceId:{}", oldAppCookie, deviceId);
             return;
         }
 
@@ -940,6 +954,19 @@ public class DistributedGroupStore
             log.warn("Current extraneous groups in device:{} are: {}",
                      deviceId,
                      getExtraneousGroups(deviceId));
+            if (operation.buckets().equals(existing.buckets())) {
+                if (existing.state() == GroupState.PENDING_ADD) {
+                    log.info("GROUP_EXISTS: GroupID and Buckets match for group in pending "
+                            + "add state - moving to ADDED for group {} in device {}",
+                            existing.id(), deviceId);
+                    addOrUpdateGroupEntry(existing);
+                    return;
+                } else {
+                    log.warn("GROUP EXISTS: Group ID matched but buckets did not. "
+                            + "Operation: {} Existing: {}", operation.buckets(),
+                            existing.buckets());
+                }
+            }
         }
         switch (operation.opType()) {
             case ADD:

@@ -1030,26 +1030,30 @@ public class OFDPA2Pipeline extends AbstractHandlerBehaviour implements Pipeline
         obj.context().ifPresent(context -> context.onError(obj, error));
     }
 
-
     @Override
     public List<String> getNextMappings(NextGroup nextGroup) {
         List<String> mappings = new ArrayList<>();
         List<Deque<GroupKey>> gkeys = appKryo.deserialize(nextGroup.data());
         for (Deque<GroupKey> gkd : gkeys) {
             Group lastGroup = null;
-            String gchain = "";
+            StringBuffer gchain = new StringBuffer();
             for (GroupKey gk : gkd) {
                 Group g = groupService.getGroup(deviceId, gk);
-                gchain += "  0x" + Integer.toHexString(g.id().id()) + " -->";
+                if (g == null) {
+                    gchain.append("  ERROR").append(" -->");
+                    continue;
+                }
+                gchain.append("  0x").append(Integer.toHexString(g.id().id()))
+                    .append(" -->");
                 lastGroup = g;
             }
             // add port information for last group in group-chain
             for (Instruction i: lastGroup.buckets().buckets().get(0).treatment().allInstructions()) {
                 if (i instanceof OutputInstruction) {
-                    gchain += " port:" + ((OutputInstruction) i).port();
+                    gchain.append(" port:").append(((OutputInstruction) i).port());
                 }
             }
-            mappings.add(gchain);
+            mappings.add(gchain.toString());
         }
         return mappings;
     }

@@ -337,11 +337,11 @@ public class OpenFlowGroupProvider extends AbstractProvider implements GroupProv
                                         GroupMsgErrorCode.values()[(code.ordinal())];
                                 GroupOperation failedOperation = GroupOperation
                                         .createFailedGroupOperation(operation, failureCode);
+                                log.warn("Received a group mod error {}", msg);
                                 providerService.groupOperationFailed(deviceId,
                                         failedOperation);
                                 pendingGroupOperations.remove(pendingGroupId);
                                 pendingXidMaps.remove(pendingGroupId);
-                                log.warn("Received a group mod error {}", msg);
                             } else {
                                 log.error("Cannot find pending group operation with group ID: {}",
                                         pendingGroupId);