/*
* Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 which accompanies this distribution,
* and is available at http://www.eclipse.org/legal/epl-v10.html
*/
package org.opendaylight.yangtools.yang.data.impl.schema.tree;
import static com.google.common.base.Preconditions.checkArgument;
import com.google.common.base.Optional;
import com.google.common.base.Preconditions;
import com.google.common.base.Verify;
import java.util.Collection;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNodeContainer;
import org.opendaylight.yangtools.yang.data.api.schema.tree.ConflictingModificationAppliedException;
import org.opendaylight.yangtools.yang.data.api.schema.tree.DataValidationFailedException;
import org.opendaylight.yangtools.yang.data.api.schema.tree.ModificationType;
import org.opendaylight.yangtools.yang.data.api.schema.tree.ModifiedNodeDoesNotExistException;
import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeConfiguration;
import org.opendaylight.yangtools.yang.data.api.schema.tree.TreeType;
import org.opendaylight.yangtools.yang.data.api.schema.tree.spi.MutableTreeNode;
import org.opendaylight.yangtools.yang.data.api.schema.tree.spi.TreeNode;
import org.opendaylight.yangtools.yang.data.api.schema.tree.spi.TreeNodeFactory;
import org.opendaylight.yangtools.yang.data.api.schema.tree.spi.Version;
import org.opendaylight.yangtools.yang.data.impl.schema.builder.api.NormalizedNodeContainerBuilder;
abstract class AbstractNodeContainerModificationStrategy extends SchemaAwareApplyOperation {
private final Class<? extends NormalizedNode<?, ?>> nodeClass;
private final boolean verifyChildrenStructure;
protected AbstractNodeContainerModificationStrategy(final Class<? extends NormalizedNode<?, ?>> nodeClass,
final DataTreeConfiguration treeConfig) {
this.nodeClass = Preconditions.checkNotNull(nodeClass , "nodeClass");
this.verifyChildrenStructure = (treeConfig.getTreeType() == TreeType.CONFIGURATION);
}
@SuppressWarnings("rawtypes")
@Override
void verifyStructure(final NormalizedNode<?, ?> writtenValue, final boolean verifyChildren) {
checkArgument(nodeClass.isInstance(writtenValue), "Node %s is not of type %s", writtenValue, nodeClass);
checkArgument(writtenValue instanceof NormalizedNodeContainer);
if (verifyChildrenStructure && verifyChildren) {
final NormalizedNodeContainer container = (NormalizedNodeContainer) writtenValue;
for (final Object child : container.getValue()) {
checkArgument(child instanceof NormalizedNode);
final NormalizedNode<?, ?> castedChild = (NormalizedNode<?, ?>) child;
final Optional<ModificationApplyOperation> childOp = getChild(castedChild.getIdentifier());
if (childOp.isPresent()) {
childOp.get().verifyStructure(castedChild, verifyChildren);
} else {
throw new SchemaValidationFailedException(String.format(
"Node %s is not a valid child of %s according to the schema.",
castedChild.getIdentifier(), container.getIdentifier()));
}
}
}
}
@Override
protected void recursivelyVerifyStructure(final NormalizedNode<?, ?> value) {
final NormalizedNodeContainer container = (NormalizedNodeContainer) value;
for (final Object child : container.getValue()) {
checkArgument(child instanceof NormalizedNode);
final NormalizedNode<?, ?> castedChild = (NormalizedNode<?, ?>) child;
final Optional<ModificationApplyOperation> childOp = getChild(castedChild.getIdentifier());
if (childOp.isPresent()) {
childOp.get().recursivelyVerifyStructure(castedChild);
} else {
throw new SchemaValidationFailedException(
String.format("Node %s is not a valid child of %s according to the schema.",
castedChild.getIdentifier(), container.getIdentifier()));
}
}
}
@Override
protected TreeNode applyWrite(final ModifiedNode modification,
final Optional<TreeNode> currentMeta, final Version version) {
final NormalizedNode<?, ?> newValue = modification.getWrittenValue();
final TreeNode newValueMeta = TreeNodeFactory.createTreeNode(newValue, version);
if (modification.getChildren().isEmpty()) {
return newValueMeta;
}
/*
* This is where things get interesting. The user has performed a write and
* then she applied some more modifications to it. So we need to make sense
* of that an apply the operations on top of the written value. We could have
* done it during the write, but this operation is potentially expensive, so
* we have left it out of the fast path.
*
* As it turns out, once we materialize the written data, we can share the
* code path with the subtree change. So let's create an unsealed TreeNode
* and run the common parts on it -- which end with the node being sealed.
*
* FIXME: this code needs to be moved out from the prepare() path and into
* the read() and seal() paths. Merging of writes needs to be charged
* to the code which originated this, not to the code which is
* attempting to make it visible.
*/
final MutableTreeNode mutable = newValueMeta.mutable();
mutable.setSubtreeVersion(version);
@SuppressWarnings("rawtypes")
final NormalizedNodeContainerBuilder dataBuilder = createBuilder(newValue);
final TreeNode result = mutateChildren(mutable, dataBuilder, version, modification.getChildren());
// We are good to go except one detail: this is a single logical write, but
// we have a result TreeNode which has been forced to materialized, e.g. it
// is larger than it needs to be. Create a new TreeNode to host the data.
return TreeNodeFactory.createTreeNode(result.getData(), version);
}
/**
* Applies write/remove diff operation for each modification child in modification subtree.
* Operation also sets the Data tree references for each Tree Node (Index Node) in meta (MutableTreeNode) structure.
*
* @param meta MutableTreeNode (IndexTreeNode)
* @param data DataBuilder
* @param nodeVersion Version of TreeNode
* @param modifications modification operations to apply
* @return Sealed immutable copy of TreeNode structure with all Data Node references set.
*/
@SuppressWarnings({ "rawtypes", "unchecked" })
private TreeNode mutateChildren(final MutableTreeNode meta, final NormalizedNodeContainerBuilder data,
final Version nodeVersion, final Iterable<ModifiedNode> modifications) {
for (final ModifiedNode mod : modifications) {
final YangInstanceIdentifier.PathArgument id = mod.getIdentifier();
final Optional<TreeNode> cm = meta.getChild(id);
final Optional<TreeNode> result = resolveChildOperation(id).apply(mod, cm, nodeVersion);
if (result.isPresent()) {
final TreeNode tn = result.get();
meta.addChild(tn);
data.addChild(tn.getData());
} else {
meta.removeChild(id);
data.removeChild(id);
}
}
meta.setData(data.build());
return meta.seal();
}
@Override
protected TreeNode applyMerge(final ModifiedNode modification, final TreeNode currentMeta, final Version version) {
/*
* The node which we are merging exists. We now need to expand any child operations implied by the value. Once
* we do that, ModifiedNode children will look like this node were a TOUCH and we will let applyTouch() do the
* heavy lifting of applying the children recursively (either through here or through applyWrite().
*/
final NormalizedNode<?, ?> value = modification.getWrittenValue();
Verify.verify(value instanceof NormalizedNodeContainer, "Attempted to merge non-container %s", value);
@SuppressWarnings({"unchecked", "rawtypes"})
final Collection<NormalizedNode<?, ?>> children = ((NormalizedNodeContainer) value).getValue();
for (final NormalizedNode<?, ?> c : children) {
final PathArgument id = c.getIdentifier();
modification.modifyChild(id, resolveChildOperation(id), version);
}
return applyTouch(modification, currentMeta, version);
}
private void mergeChildrenIntoModification(final ModifiedNode modification,
final Collection<NormalizedNode<?, ?>> children, final Version version) {
for (final NormalizedNode<?, ?> c : children) {
final ModificationApplyOperation childOp = resolveChildOperation(c.getIdentifier());
final ModifiedNode childNode = modification.modifyChild(c.getIdentifier(), childOp, version);
childOp.mergeIntoModifiedNode(childNode, c, version);
}
}
@Override
final void mergeIntoModifiedNode(final ModifiedNode modification, final NormalizedNode<?, ?> value,
final Version version) {
@SuppressWarnings({ "unchecked", "rawtypes" })
final Collection<NormalizedNode<?, ?>> children = ((NormalizedNodeContainer)value).getValue();
switch (modification.getOperation()) {
case NONE:
// Fresh node, just record a MERGE with a value
recursivelyVerifyStructure(value);
modification.updateValue(LogicalOperation.MERGE, value);
return;
case TOUCH:
mergeChildrenIntoModification(modification, children, version);
// We record empty merge value, since real children merges
// are already expanded. This is needed to satisfy non-null for merge
// original merge value can not be used since it mean different
// order of operation - parent changes are always resolved before
// children ones, and having node in TOUCH means children was modified
// before.
modification.updateValue(LogicalOperation.MERGE, createEmptyValue(value));
return;
case MERGE:
// Merging into an existing node. Merge data children modifications (maybe recursively) and mark as MERGE,
// invalidating cached snapshot
mergeChildrenIntoModification(modification, children, version);
modification.updateOperationType(LogicalOperation.MERGE);
return;
case DELETE:
// Delete performs a data dependency check on existence of the node. Performing a merge on DELETE means we
// are really performing a write. One thing that ruins that are any child modifications. If there are any,
// we will perform a read() to get the current state of affairs, turn this into into a WRITE and then
// append any child entries.
if (!modification.getChildren().isEmpty()) {
// Version does not matter here as we'll throw it out
final Optional<TreeNode> current = apply(modification, modification.getOriginal(), Version.initial());
if (current.isPresent()) {
modification.updateValue(LogicalOperation.WRITE, current.get().getData());
mergeChildrenIntoModification(modification, children, version);
return;
}
}
modification.updateValue(LogicalOperation.WRITE, value);
return;
case WRITE:
// We are augmenting a previous write. We'll just walk value's children, get the corresponding ModifiedNode
// and run recursively on it
mergeChildrenIntoModification(modification, children, version);
modification.updateOperationType(LogicalOperation.WRITE);
return;
}
throw new IllegalArgumentException("Unsupported operation " + modification.getOperation());
}
@Override
protected TreeNode applyTouch(final ModifiedNode modification, final TreeNode currentMeta, final Version version) {
/*
* The user may have issued an empty merge operation. In this case we do not perform
* a data tree mutation, do not pass GO, and do not collect useless garbage. It
* also means the ModificationType is UNMODIFIED.
*/
final Collection<ModifiedNode> children = modification.getChildren();
if (!children.isEmpty()) {
@SuppressWarnings("rawtypes")
final NormalizedNodeContainerBuilder dataBuilder = createBuilder(currentMeta.getData());
final MutableTreeNode newMeta = currentMeta.mutable();
newMeta.setSubtreeVersion(version);
final TreeNode ret = mutateChildren(newMeta, dataBuilder, version, children);
/*
* It is possible that the only modifications under this node were empty merges,
* which were turned into UNMODIFIED. If that is the case, we can turn this operation
* into UNMODIFIED, too, potentially cascading it up to root. This has the benefit
* of speeding up any users, who can skip processing child nodes.
*
* In order to do that, though, we have to check all child operations are UNMODIFIED.
* Let's do precisely that, stopping as soon we find a different result.
*/
for (final ModifiedNode child : children) {
if (child.getModificationType() != ModificationType.UNMODIFIED) {
modification.resolveModificationType(ModificationType.SUBTREE_MODIFIED);
return ret;
}
}
}
// The merge operation did not have any children, or all of them turned out to be UNMODIFIED, hence do not
// replace the metadata node.
modification.resolveModificationType(ModificationType.UNMODIFIED);
return currentMeta;
}
@Override
protected void checkTouchApplicable(final YangInstanceIdentifier path, final NodeModification modification,
final Optional<TreeNode> current, final Version version) throws DataValidationFailedException {
if (!modification.getOriginal().isPresent() && !current.isPresent()) {
throw new ModifiedNodeDoesNotExistException(path, String.format("Node %s does not exist. Cannot apply modification to its children.", path));
}
if (!current.isPresent()) {
throw new ConflictingModificationAppliedException(path, "Node was deleted by other transaction.");
}
checkChildPreconditions(path, modification, current.get(), version);
}
/**
* Recursively check child preconditions.
*
* @param path current node path
* @param modification current modification
* @param current Current data tree node.
*/
private void checkChildPreconditions(final YangInstanceIdentifier path, final NodeModification modification,
final TreeNode current, final Version version) throws DataValidationFailedException {
for (final NodeModification childMod : modification.getChildren()) {
final YangInstanceIdentifier.PathArgument childId = childMod.getIdentifier();
final Optional<TreeNode> childMeta = current.getChild(childId);
final YangInstanceIdentifier childPath = path.node(childId);
resolveChildOperation(childId).checkApplicable(childPath, childMod, childMeta, version);
}
}
@Override
protected void checkMergeApplicable(final YangInstanceIdentifier path, final NodeModification modification,
final Optional<TreeNode> current, final Version version) throws DataValidationFailedException {
if (current.isPresent()) {
checkChildPreconditions(path, modification, current.get(), version);
}
}
protected boolean verifyChildrenStructure() {
return verifyChildrenStructure;
}
@SuppressWarnings("rawtypes")
protected abstract NormalizedNodeContainerBuilder createBuilder(NormalizedNode<?, ?> original);
protected abstract NormalizedNode<?, ?> createEmptyValue(NormalizedNode<?, ?> original);
}