/*
* 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 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.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.mdsal.dom.api.DOMTransactionChain;
import org.opendaylight.netconf.dom.api.NetconfDataTreeService;
import org.opendaylight.restconf.api.query.PointParam;
import org.opendaylight.restconf.common.errors.RestconfFuture;
import org.opendaylight.restconf.common.errors.SettableRestconfFuture;
import org.opendaylight.restconf.nb.rfc8040.WriteDataParams;
import org.opendaylight.restconf.nb.rfc8040.rests.utils.PostDataTransactionUtil;
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.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.model.api.EffectiveModelContext;
import org.opendaylight.yangtools.yang.model.api.SchemaContext;
/**
* 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;
}
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 datastore.
*
* @param store the logical data store which should be modified
* @param path the data object path
* @return a FluentFuture containing the result of the check
*/
public abstract ListenableFuture exists(LogicalDatastoreType store, 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. Close {@link DOMTransactionChain} if any
* inside of object {@link RestconfStrategy} provided as a parameter if any.
*
* @param path path of data
* @param data data
* @param schemaContext reference to {@link EffectiveModelContext}
* @param params {@link WriteDataParams}
* @return A {@link CreateOrReplaceResult}
*/
public @NonNull CreateOrReplaceResult putData(final YangInstanceIdentifier path, final NormalizedNode data,
final EffectiveModelContext schemaContext, final WriteDataParams params) {
final var exists = TransactionUtil.syncAccess(exists(LogicalDatastoreType.CONFIGURATION, path), path);
TransactionUtil.syncCommit(submitData(path, schemaContext, data, params), "PUT", path);
return exists ? CreateOrReplaceResult.REPLACED : CreateOrReplaceResult.CREATED;
}
/**
* Put data to DS.
*
* @param path path of data
* @param schemaContext {@link SchemaContext}
* @param data data
* @param params {@link WriteDataParams}
* @return A {@link ListenableFuture}
*/
private ListenableFuture extends CommitInfo> submitData(final YangInstanceIdentifier path,
final EffectiveModelContext schemaContext, final NormalizedNode data, final WriteDataParams params) {
final var transaction = prepareWriteExecution();
final var insert = params.insert();
if (insert == null) {
return makePut(path, schemaContext, transaction, data);
}
final var parentPath = path.coerceParent();
PostDataTransactionUtil.checkListAndOrderedType(schemaContext, parentPath);
return switch (insert) {
case FIRST -> {
final var readData = transaction.readList(parentPath);
if (readData == null || readData.isEmpty()) {
yield makePut(path, schemaContext, transaction, data);
}
transaction.remove(parentPath);
transaction.replace(path, data, schemaContext);
transaction.replace(parentPath, readData, schemaContext);
yield transaction.commit();
}
case LAST -> makePut(path, schemaContext, transaction, data);
case BEFORE -> {
final var readData = transaction.readList(parentPath);
if (readData == null || readData.isEmpty()) {
yield makePut(path, schemaContext, transaction, data);
}
insertWithPointPut(transaction, path, data, schemaContext, params.getPoint(), readData, true);
yield transaction.commit();
}
case AFTER -> {
final var readData = transaction.readList(parentPath);
if (readData == null || readData.isEmpty()) {
yield makePut(path, schemaContext, transaction, data);
}
insertWithPointPut(transaction, path, data, schemaContext, params.getPoint(), readData, false);
yield transaction.commit();
}
};
}
private static void insertWithPointPut(final RestconfTransaction transaction, final YangInstanceIdentifier path,
final NormalizedNode data, final EffectiveModelContext schemaContext, final PointParam point,
final NormalizedNodeContainer> readList, final boolean before) {
transaction.remove(path.getParent());
final var pointArg = YangInstanceIdentifierDeserializer.create(schemaContext, 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(schemaContext, path.getParent());
transaction.merge(YangInstanceIdentifier.of(emptySubtree.name()), emptySubtree);
for (var nodeChild : readList.body()) {
if (lastInsertedPosition == lastItemPosition) {
transaction.replace(path, data, schemaContext);
}
final var childPath = path.coerceParent().node(nodeChild.name());
transaction.replace(childPath, nodeChild, schemaContext);
lastInsertedPosition++;
}
}
private static ListenableFuture extends CommitInfo> makePut(final YangInstanceIdentifier path,
final EffectiveModelContext schemaContext, final RestconfTransaction transaction,
final NormalizedNode data) {
transaction.replace(path, data, schemaContext);
return transaction.commit();
}
}