BUG-5280: add basic concept of ClientSnapshot

[controller.git] / opendaylight / md-sal / sal-distributed-datastore / src / main / java / org / opendaylight / controller / cluster / datastore / AbstractFrontendHistory.java

diff --git a/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/AbstractFrontendHistory.java b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/AbstractFrontendHistory.java
index 7ddad749d26552676a8057b40ca7526677bac130..7c2ddb05b22ba07fba5503615c723b90d38681c4 100644 (file)
--- a/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/AbstractFrontendHistory.java
+++ b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/AbstractFrontendHistory.java
@@ -13,6 +13,7 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.Optional;
 import javax.annotation.Nullable;
+import org.opendaylight.controller.cluster.access.commands.AbstractReadTransactionRequest;
 import org.opendaylight.controller.cluster.access.commands.CommitLocalTransactionRequest;
 import org.opendaylight.controller.cluster.access.commands.OutOfOrderRequestException;
 import org.opendaylight.controller.cluster.access.commands.TransactionRequest;
@@ -67,25 +68,39 @@ abstract class AbstractFrontendHistory implements Identifiable<LocalHistoryIdent
                 throw UNSEQUENCED_START;
             }
 
-            if (request instanceof CommitLocalTransactionRequest) {
-                tx = createReadyTransaction(id, ((CommitLocalTransactionRequest) request).getModification());
-                LOG.debug("{}: allocated new ready transaction {}", persistenceId(), id);
-            } else {
-                tx = createOpenTransaction(id);
-                LOG.debug("{}: allocated new open transaction {}", persistenceId(), id);
-            }
-
+            tx = createTransaction(request, id);
             transactions.put(id, tx);
         } else {
-            final Optional<TransactionSuccess<?>> replay = tx.replaySequence(request.getSequence());
-            if (replay.isPresent()) {
-                return replay.get();
+            final Optional<TransactionSuccess<?>> maybeReplay = tx.replaySequence(request.getSequence());
+            if (maybeReplay.isPresent()) {
+                final TransactionSuccess<?> replay = maybeReplay.get();
+                LOG.debug("{}: envelope {} replaying response {}", persistenceId(), envelope, replay);
+                return replay;
             }
         }
 
         return tx.handleRequest(request, envelope, now);
     }
 
+    private FrontendTransaction createTransaction(final TransactionRequest<?> request, final TransactionIdentifier id)
+            throws RequestException {
+        if (request instanceof CommitLocalTransactionRequest) {
+            LOG.debug("{}: allocating new ready transaction {}", persistenceId(), id);
+            return createReadyTransaction(id, ((CommitLocalTransactionRequest) request).getModification());
+        }
+        if (request instanceof AbstractReadTransactionRequest) {
+            if (((AbstractReadTransactionRequest<?>) request).isSnapshotOnly()) {
+                LOG.debug("{}: allocatint new open snapshot {}", persistenceId(), id);
+                return createOpenSnapshot(id);
+            }
+        }
+
+        LOG.debug("{}: allocating new open transaction {}", persistenceId(), id);
+        return createOpenTransaction(id);
+    }
+
+    abstract FrontendTransaction createOpenSnapshot(TransactionIdentifier id) throws RequestException;
+
     abstract FrontendTransaction createOpenTransaction(TransactionIdentifier id) throws RequestException;
 
     abstract FrontendTransaction createReadyTransaction(TransactionIdentifier id, DataTreeModification mod)