1 files changed, 47 insertions, 22 deletions

diff --git a/infra/data-impl/src/main/java/io/fd/honeycomb/data/impl/ModifiableDataTreeManager.java b/infra/data-impl/src/main/java/io/fd/honeycomb/data/impl/ModifiableDataTreeManager.java
index f16172fa5..aa5b3e5cf 100644
--- a/infra/data-impl/src/main/java/io/fd/honeycomb/data/impl/ModifiableDataTreeManager.java
+++ b/infra/data-impl/src/main/java/io/fd/honeycomb/data/impl/ModifiableDataTreeManager.java
@@ -17,12 +17,14 @@
 package io.fd.honeycomb.data.impl;
 
 import static com.google.common.base.Preconditions.checkNotNull;
+import static com.google.common.base.Preconditions.checkState;
 import static com.google.common.util.concurrent.Futures.immediateCheckedFuture;
 
 import com.google.common.base.Optional;
 import com.google.common.util.concurrent.CheckedFuture;
 import io.fd.honeycomb.data.DataModification;
 import io.fd.honeycomb.data.ModifiableDataManager;
+import io.fd.honeycomb.translate.ValidationFailedException;
 import io.fd.honeycomb.translate.TranslationException;
 import javax.annotation.Nonnull;
 import org.apache.commons.lang3.builder.RecursiveToStringStyle;
@@ -30,9 +32,12 @@ import org.apache.commons.lang3.builder.ReflectionToStringBuilder;
 import org.opendaylight.controller.md.sal.common.api.data.ReadFailedException;
 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
+import org.opendaylight.yangtools.yang.data.api.schema.tree.CursorAwareDataTreeModification;
 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTree;
 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
+import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModificationCursor;
+import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataValidationFailedException;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -61,11 +66,12 @@ public class ModifiableDataTreeManager implements ModifiableDataManager {
     }
 
     protected class ConfigSnapshot implements DataModification {
+        private final DataTreeSnapshot snapshot;
         private final DataTreeModification modification;
-        private boolean validated = false;
 
         ConfigSnapshot() {
-            this.modification = dataTree.takeSnapshot().newModification();
+            this.snapshot = dataTree.takeSnapshot();
+            this.modification = snapshot.newModification();
         }
 
         @Override
@@ -95,39 +101,58 @@ public class ModifiableDataTreeManager implements ModifiableDataManager {
         }
 
         @Override
-        public final void commit() throws DataValidationFailedException, TranslationException {
-            if(!validated) {
-                validate();
-            }
-            final DataTreeCandidate candidate = dataTree.prepare(modification);
+        public final void commit() throws TranslationException {
+            final DataTreeCandidate candidate = prepareCandidate(modification);
+            validateCandidate(candidate);
             processCandidate(candidate);
             dataTree.commit(candidate);
         }
 
+        private DataTreeCandidate prepareCandidate(final DataTreeModification dataTreeModification)
+            throws ValidationFailedException {
+            // Seal the modification (required to perform validate)
+            dataTreeModification.ready();
+
+            // Check if modification can be applied to data tree
+            try {
+                dataTree.validate(dataTreeModification);
+            } catch (DataValidationFailedException e) {
+                throw new ValidationFailedException(e);
+            }
+
+            return dataTree.prepare(dataTreeModification);
+        }
+
+        protected void validateCandidate(final DataTreeCandidate candidate) throws ValidationFailedException {
+            // NOOP
+        }
+
         protected void processCandidate(final DataTreeCandidate candidate) throws TranslationException {
             // NOOP
         }
 
         @Override
-        public final void validate() throws DataValidationFailedException {
-            modification.ready();
-            dataTree.validate(modification);
-            validated = true;
+        public final void validate() throws ValidationFailedException {
+            // Modification requires to be sealed before validation.
+            // Sealed modification cannot be altered, so create copy.
+            final CursorAwareDataTreeModification modificationCopy =
+                (CursorAwareDataTreeModification) snapshot.newModification();
+            final DataTreeModificationCursor cursor = modificationCopy.createCursor(dataTree.getRootPath());
+            checkState(cursor != null, "DataTreeModificationCursor for root path should not be null");
+            modification.applyToCursor(cursor);
+            // Then validate it.
+            validateCandidate(prepareCandidate(modificationCopy));
         }
 
         @Override
         public String toString() {
-            return "ConfigSnapshot{" +
-                    "modification=" +
-                    ReflectionToStringBuilder.toString(
-                            modification,
-                            RecursiveToStringStyle.MULTI_LINE_STYLE,
-                            false,
-                            false
-                    ) + ", validated=" + validated + '}';
+            return "ConfigSnapshot{modification="
+                + ReflectionToStringBuilder.toString(
+                modification,
+                RecursiveToStringStyle.MULTI_LINE_STYLE,
+                false,
+                false
+            ) + '}';
         }
     }
 }
-
-
-