/*
* Copyright (c) 2020 PANTHEON.tech, s.r.o. 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.restconf.nb.rfc8040.rests.transactions;
import static com.google.common.base.Verify.verifyNotNull;
import static java.util.Objects.requireNonNull;
import com.google.common.util.concurrent.FutureCallback;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.MoreExecutors;
import java.util.List;
import java.util.Optional;
import org.eclipse.jdt.annotation.NonNull;
import org.eclipse.jdt.annotation.Nullable;
import org.opendaylight.mdsal.common.api.CommitInfo;
import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
import org.opendaylight.mdsal.dom.api.DOMDataBroker;
import org.opendaylight.mdsal.dom.api.DOMMountPoint;
import org.opendaylight.netconf.dom.api.NetconfDataTreeService;
import org.opendaylight.restconf.api.query.PointParam;
import org.opendaylight.restconf.common.errors.RestconfDocumentedException;
import org.opendaylight.restconf.common.errors.RestconfFuture;
import org.opendaylight.restconf.common.errors.SettableRestconfFuture;
import org.opendaylight.restconf.nb.rfc8040.Insert;
import org.opendaylight.restconf.nb.rfc8040.rests.utils.TransactionUtil;
import org.opendaylight.restconf.nb.rfc8040.utils.parser.YangInstanceIdentifierDeserializer;
import org.opendaylight.yangtools.yang.common.Empty;
import org.opendaylight.yangtools.yang.common.ErrorTag;
import org.opendaylight.yangtools.yang.common.ErrorType;
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.NormalizedNodeContainer;
import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
import org.opendaylight.yangtools.yang.data.util.DataSchemaContextTree;
import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
import org.opendaylight.yangtools.yang.model.api.LeafListSchemaNode;
import org.opendaylight.yangtools.yang.model.api.ListSchemaNode;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Baseline execution strategy for various RESTCONF operations.
*
* @see NetconfRestconfStrategy
* @see MdsalRestconfStrategy
*/
// FIXME: it seems the first three operations deal with lifecycle of a transaction, while others invoke various
// operations. This should be handled through proper allocation indirection.
public abstract class RestconfStrategy {
/**
* Result of a {@code PUT} request as defined in
* RFC8040 section 4.5. The definition makes it
* clear that the logical operation is {@code create-or-replace}.
*/
public enum CreateOrReplaceResult {
/**
* A new resource has been created.
*/
CREATED,
/*
* An existing resources has been replaced.
*/
REPLACED;
}
private static final Logger LOG = LoggerFactory.getLogger(RestconfStrategy.class);
RestconfStrategy() {
// Hidden on purpose
}
/**
* Look up the appropriate strategy for a particular mount point.
*
* @param mountPoint Target mount point
* @return A strategy, or null if the mount point does not expose a supported interface
* @throws NullPointerException if {@code mountPoint} is null
*/
public static Optional forMountPoint(final DOMMountPoint mountPoint) {
final Optional netconf = mountPoint.getService(NetconfDataTreeService.class)
.map(NetconfRestconfStrategy::new);
if (netconf.isPresent()) {
return netconf;
}
return mountPoint.getService(DOMDataBroker.class).map(MdsalRestconfStrategy::new);
}
/**
* Lock the entire datastore.
*
* @return A {@link RestconfTransaction}. This transaction needs to be either committed or canceled before doing
* anything else.
*/
public abstract RestconfTransaction prepareWriteExecution();
/**
* Read data from the datastore.
*
* @param store the logical data store which should be modified
* @param path the data object path
* @return a ListenableFuture containing the result of the read
*/
public abstract ListenableFuture> read(LogicalDatastoreType store,
YangInstanceIdentifier path);
/**
* Read data selected using fields from the datastore.
*
* @param store the logical data store which should be modified
* @param path the parent data object path
* @param fields paths to selected fields relative to parent path
* @return a ListenableFuture containing the result of the read
*/
public abstract ListenableFuture> read(LogicalDatastoreType store,
YangInstanceIdentifier path, List fields);
/**
* Check if data already exists in the configuration datastore.
*
* @param path the data object path
* @return a ListenableFuture containing the result of the check
*/
// FIXME: this method should be hosted in RestconfTransaction
// FIXME: this method should only be needed in MdsalRestconfStrategy
abstract ListenableFuture exists(YangInstanceIdentifier path);
/**
* Delete data from the configuration datastore. If the data does not exist, this operation will fail, as outlined
* in RFC8040 section 4.7
*
* @param path Path to delete
* @return A {@link RestconfFuture}
* @throws NullPointerException if {@code path} is {@code null}
*/
public final @NonNull RestconfFuture delete(final YangInstanceIdentifier path) {
final var ret = new SettableRestconfFuture();
delete(ret, requireNonNull(path));
return ret;
}
protected abstract void delete(@NonNull SettableRestconfFuture future, @NonNull YangInstanceIdentifier path);
/**
* Merge data into the configuration datastore, as outlined in
* RFC8040 section 4.6.1.
*
* @param path Path to merge
* @param data Data to merge
* @param context Corresponding EffectiveModelContext
* @return A {@link RestconfFuture}
* @throws NullPointerException if any argument is {@code null}
*/
public final @NonNull RestconfFuture merge(final YangInstanceIdentifier path, final NormalizedNode data,
final EffectiveModelContext context) {
final var ret = new SettableRestconfFuture();
merge(ret, requireNonNull(path), requireNonNull(data), requireNonNull(context));
return ret;
}
private void merge(final @NonNull SettableRestconfFuture future,
final @NonNull YangInstanceIdentifier path, final @NonNull NormalizedNode data,
final @NonNull EffectiveModelContext context) {
final var tx = prepareWriteExecution();
// FIXME: this method should be further specialized to eliminate this call -- it is only needed for MD-SAL
TransactionUtil.ensureParentsByMerge(path, context, tx);
tx.merge(path, data);
Futures.addCallback(tx.commit(), new FutureCallback() {
@Override
public void onSuccess(final CommitInfo result) {
future.set(Empty.value());
}
@Override
public void onFailure(final Throwable cause) {
future.setFailure(TransactionUtil.decodeException(cause, "MERGE", path));
}
}, MoreExecutors.directExecutor());
}
/**
* Check mount point and prepare variables for put data to DS.
*
* @param path path of data
* @param data data
* @param context reference to {@link EffectiveModelContext}
* @param insert {@link Insert}
* @return A {@link CreateOrReplaceResult}
*/
public @NonNull CreateOrReplaceResult putData(final YangInstanceIdentifier path, final NormalizedNode data,
final EffectiveModelContext context, final @Nullable Insert insert) {
final var exists = TransactionUtil.syncAccess(exists(path), path);
final ListenableFuture extends CommitInfo> commitFuture;
if (insert != null) {
final var parentPath = path.coerceParent();
checkListAndOrderedType(context, parentPath);
commitFuture = insertAndCommitPut(path, data, insert, parentPath, context);
} else {
commitFuture = replaceAndCommit(prepareWriteExecution(), path, data, context);
}
TransactionUtil.syncCommit(commitFuture, "PUT", path);
return exists ? CreateOrReplaceResult.REPLACED : CreateOrReplaceResult.CREATED;
}
private ListenableFuture extends CommitInfo> insertAndCommitPut(final YangInstanceIdentifier path,
final NormalizedNode data, final @NonNull Insert insert, final YangInstanceIdentifier parentPath,
final EffectiveModelContext context) {
final var tx = prepareWriteExecution();
return switch (insert.insert()) {
case FIRST -> {
final var readData = tx.readList(parentPath);
if (readData == null || readData.isEmpty()) {
yield replaceAndCommit(tx, path, data, context);
}
tx.remove(parentPath);
tx.replace(path, data, context);
tx.replace(parentPath, readData, context);
yield tx.commit();
}
case LAST -> replaceAndCommit(tx, path, data, context);
case BEFORE -> {
final var readData = tx.readList(parentPath);
if (readData == null || readData.isEmpty()) {
yield replaceAndCommit(tx, path, data, context);
}
insertWithPointPut(tx, path, data, verifyNotNull(insert.point()), readData, true, context);
yield tx.commit();
}
case AFTER -> {
final var readData = tx.readList(parentPath);
if (readData == null || readData.isEmpty()) {
yield replaceAndCommit(tx, path, data, context);
}
insertWithPointPut(tx, path, data, verifyNotNull(insert.point()), readData, false, context);
yield tx.commit();
}
};
}
private static void insertWithPointPut(final RestconfTransaction tx, final YangInstanceIdentifier path,
final NormalizedNode data, final @NonNull PointParam point, final NormalizedNodeContainer> readList,
final boolean before, final EffectiveModelContext context) {
tx.remove(path.getParent());
final var pointArg = YangInstanceIdentifierDeserializer.create(context, point.value()).path
.getLastPathArgument();
int lastItemPosition = 0;
for (var nodeChild : readList.body()) {
if (nodeChild.name().equals(pointArg)) {
break;
}
lastItemPosition++;
}
if (!before) {
lastItemPosition++;
}
int lastInsertedPosition = 0;
final var emptySubtree = ImmutableNodes.fromInstanceId(context, path.getParent());
tx.merge(YangInstanceIdentifier.of(emptySubtree.name()), emptySubtree);
for (var nodeChild : readList.body()) {
if (lastInsertedPosition == lastItemPosition) {
tx.replace(path, data, context);
}
final var childPath = path.coerceParent().node(nodeChild.name());
tx.replace(childPath, nodeChild, context);
lastInsertedPosition++;
}
}
private static ListenableFuture extends CommitInfo> replaceAndCommit(final RestconfTransaction tx,
final YangInstanceIdentifier path, final NormalizedNode data, final EffectiveModelContext context) {
tx.replace(path, data, context);
return tx.commit();
}
private static DataSchemaNode checkListAndOrderedType(final EffectiveModelContext ctx,
final YangInstanceIdentifier path) {
final var dataSchemaNode = DataSchemaContextTree.from(ctx).findChild(path).orElseThrow().dataSchemaNode();
final String message;
if (dataSchemaNode instanceof ListSchemaNode listSchema) {
if (listSchema.isUserOrdered()) {
return listSchema;
}
message = "Insert parameter can be used only with ordered-by user list.";
} else if (dataSchemaNode instanceof LeafListSchemaNode leafListSchema) {
if (leafListSchema.isUserOrdered()) {
return leafListSchema;
}
message = "Insert parameter can be used only with ordered-by user leaf-list.";
} else {
message = "Insert parameter can be used only with list or leaf-list";
}
throw new RestconfDocumentedException(message, ErrorType.PROTOCOL, ErrorTag.BAD_ELEMENT);
}
/**
* Check mount point and prepare variables for post data.
*
* @param path path
* @param data data
* @param context reference to actual {@link EffectiveModelContext}
* @param insert {@link Insert}
*/
public final void postData(final YangInstanceIdentifier path, final NormalizedNode data,
final EffectiveModelContext context, final @Nullable Insert insert) {
final ListenableFuture extends CommitInfo> future;
if (insert != null) {
final var parentPath = path.coerceParent();
checkListAndOrderedType(context, parentPath);
future = insertAndCommitPost(path, data, insert, parentPath, context);
} else {
future = createAndCommit(prepareWriteExecution(), path, data, context);
}
TransactionUtil.syncCommit(future, "POST", path);
}
private ListenableFuture extends CommitInfo> insertAndCommitPost(final YangInstanceIdentifier path,
final NormalizedNode data, final @NonNull Insert insert, final YangInstanceIdentifier parent,
final EffectiveModelContext context) {
final var grandParent = parent.coerceParent();
final var tx = prepareWriteExecution();
return switch (insert.insert()) {
case FIRST -> {
final var readData = tx.readList(grandParent);
if (readData == null || readData.isEmpty()) {
tx.replace(path, data, context);
} else {
checkItemDoesNotExists(exists(path), path);
tx.remove(grandParent);
tx.replace(path, data, context);
tx.replace(grandParent, readData, context);
}
yield tx.commit();
}
case LAST -> createAndCommit(tx, path, data, context);
case BEFORE -> {
final var readData = tx.readList(grandParent);
if (readData == null || readData.isEmpty()) {
tx.replace(path, data, context);
} else {
checkItemDoesNotExists(exists(path), path);
insertWithPointPost(tx, path, data, verifyNotNull(insert.point()), readData, grandParent, true,
context);
}
yield tx.commit();
}
case AFTER -> {
final var readData = tx.readList(grandParent);
if (readData == null || readData.isEmpty()) {
tx.replace(path, data, context);
} else {
checkItemDoesNotExists(exists(path), path);
insertWithPointPost(tx, path, data, verifyNotNull(insert.point()), readData, grandParent, false,
context);
}
yield tx.commit();
}
};
}
private static void insertWithPointPost(final RestconfTransaction tx, final YangInstanceIdentifier path,
final NormalizedNode data, final PointParam point, final NormalizedNodeContainer> readList,
final YangInstanceIdentifier grandParentPath, final boolean before, final EffectiveModelContext context) {
tx.remove(grandParentPath);
final var pointArg = YangInstanceIdentifierDeserializer.create(context, point.value()).path
.getLastPathArgument();
int lastItemPosition = 0;
for (var nodeChild : readList.body()) {
if (nodeChild.name().equals(pointArg)) {
break;
}
lastItemPosition++;
}
if (!before) {
lastItemPosition++;
}
int lastInsertedPosition = 0;
final var emptySubtree = ImmutableNodes.fromInstanceId(context, grandParentPath);
tx.merge(YangInstanceIdentifier.of(emptySubtree.name()), emptySubtree);
for (var nodeChild : readList.body()) {
if (lastInsertedPosition == lastItemPosition) {
tx.replace(path, data, context);
}
final YangInstanceIdentifier childPath = grandParentPath.node(nodeChild.name());
tx.replace(childPath, nodeChild, context);
lastInsertedPosition++;
}
}
private static ListenableFuture extends CommitInfo> createAndCommit(final RestconfTransaction tx,
final YangInstanceIdentifier path, final NormalizedNode data, final EffectiveModelContext context) {
try {
tx.create(path, data, context);
} catch (RestconfDocumentedException e) {
// close transaction if any and pass exception further
tx.cancel();
throw e;
}
return tx.commit();
}
/**
* Check if items do NOT already exists at specified {@code path}.
*
* @param existsFuture if checked data exists
* @param path Path to be checked
* @throws RestconfDocumentedException if data already exists.
*/
static void checkItemDoesNotExists(final ListenableFuture existsFuture,
final YangInstanceIdentifier path) {
if (TransactionUtil.syncAccess(existsFuture, path)) {
LOG.trace("Operation via Restconf was not executed because data at {} already exists", path);
throw new RestconfDocumentedException("Data already exists", ErrorType.PROTOCOL, ErrorTag.DATA_EXISTS,
path);
}
}
}