/*
* 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.mdsal.binding.dom.codec.impl;
import static com.google.common.base.Preconditions.checkArgument;
import com.google.common.collect.ImmutableListMultimap;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableMap.Builder;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import com.google.common.collect.Lists;
import com.google.common.collect.MultimapBuilder.SetMultimapBuilder;
import com.google.common.collect.Multimaps;
import com.google.common.collect.SetMultimap;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Optional;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import org.eclipse.jdt.annotation.NonNull;
import org.opendaylight.mdsal.binding.spec.reflect.BindingReflections;
import org.opendaylight.yangtools.yang.binding.DataObject;
import org.opendaylight.yangtools.yang.binding.InstanceIdentifier.PathArgument;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
import org.opendaylight.yangtools.yang.data.api.schema.ChoiceNode;
import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
import org.opendaylight.yangtools.yang.data.util.DataSchemaContextNode;
import org.opendaylight.yangtools.yang.data.util.NormalizedNodeSchemaUtils;
import org.opendaylight.yangtools.yang.model.api.AugmentationSchemaNode;
import org.opendaylight.yangtools.yang.model.api.CaseSchemaNode;
import org.opendaylight.yangtools.yang.model.api.ChoiceSchemaNode;
import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* This is a bit tricky. DataObject addressing does not take into account choice/case statements, and hence given:
*
*
*
* container foo {
* choice bar {
* leaf baz;
* }
* }
*
*
* we will see {@code Baz extends ChildOf}, which is how the users would address it in InstanceIdentifier terms.
* The implicit assumption being made is that {@code Baz} identifies a particular instantiation and hence provides
* unambiguous reference to an effective schema statement.
*
*
* Unfortunately this does not quite work with groupings, as their generation has changed: we do not have interfaces
* that would capture grouping instantiations, hence we do not have a proper addressing point and users need to specify
* the interfaces generated in the grouping's definition. These can be very much ambiguous, as a {@code grouping} can be
* used in multiple modules independently within an {@code augment} targeting {@code choice}, as each instantiation is
* guaranteed to have a unique namespace -- but we do not have the appropriate instantiations of those nodes.
*
*
* To address this issue we have a two-class lookup mechanism, which relies on the interface generated for the
* {@code case} statement to act as the namespace anchor bridging the nodes inside the grouping to the namespace in
* which they are instantiated.
*
*
* Furthermore downstream code relies on historical mechanics, which would guess what the instantiation is, silently
* assuming the ambiguity is theoretical and does not occur in practice.
*
*
* This leads to three classes of addressing, in order descending performance requirements.
*
* - Direct DataObject, where we name an exact child
* - Case DataObject + Grouping DataObject
* - Grouping DataObject, which is ambiguous
*
*
* {@link #byCaseChildClass} supports direct DataObject mapping and contains only unambiguous children, while
* {@link #byClass} supports indirect mapping and contains {@code case} sub-statements.
*
* {@link #ambiguousByCaseChildClass} contains ambiguous mappings, for which we end up issuing warnings. We track each
* ambiguous reference and issue warn once when they are encountered -- tracking warning information in
* {@link #ambiguousByCaseChildWarnings}.
*/
final class ChoiceNodeCodecContext extends DataContainerCodecContext {
private static final Logger LOG = LoggerFactory.getLogger(ChoiceNodeCodecContext.class);
private final ImmutableMap> byYangCaseChild;
private final ImmutableListMultimap, DataContainerCodecPrototype>> ambiguousByCaseChildClass;
private final ImmutableMap, DataContainerCodecPrototype>> byCaseChildClass;
private final ImmutableMap, DataContainerCodecPrototype>> byClass;
private final Set> ambiguousByCaseChildWarnings;
ChoiceNodeCodecContext(final DataContainerCodecPrototype prototype) {
super(prototype);
final Map> byYangCaseChildBuilder =
new HashMap<>();
final Map, DataContainerCodecPrototype>> byClassBuilder = new HashMap<>();
final SetMultimap, DataContainerCodecPrototype>> childToCase =
SetMultimapBuilder.hashKeys().hashSetValues().build();
final Set> potentialSubstitutions = new HashSet<>();
// Walks all cases for supplied choice in current runtime context
for (final Class> caze : factory().getRuntimeContext().getCases(getBindingClass())) {
// We try to load case using exact match thus name
// and original schema must equals
final DataContainerCodecPrototype cazeDef = loadCase(caze);
// If we have case definition, this case is instantiated
// at current location and thus is valid in context of parent choice
if (cazeDef != null) {
byClassBuilder.put(cazeDef.getBindingClass(), cazeDef);
// Updates collection of case children
@SuppressWarnings("unchecked")
final Class extends DataObject> cazeCls = (Class extends DataObject>) caze;
for (final Class extends DataObject> cazeChild : BindingReflections.getChildrenClasses(cazeCls)) {
childToCase.put(cazeChild, cazeDef);
}
// Updates collection of YANG instance identifier to case
for (final DataSchemaNode cazeChild : cazeDef.getSchema().getChildNodes()) {
if (cazeChild.isAugmenting()) {
final AugmentationSchemaNode augment =
NormalizedNodeSchemaUtils.findCorrespondingAugment(cazeDef.getSchema(), cazeChild);
if (augment != null) {
byYangCaseChildBuilder.put(DataSchemaContextNode.augmentationIdentifierFrom(augment),
cazeDef);
continue;
}
}
byYangCaseChildBuilder.put(NodeIdentifier.create(cazeChild.getQName()), cazeDef);
}
} else {
/*
* If case definition is not available, we store it for
* later check if it could be used as substitution of existing one.
*/
potentialSubstitutions.add(caze);
}
}
byYangCaseChild = ImmutableMap.copyOf(byYangCaseChildBuilder);
// Move unambiguous child->case mappings to byCaseChildClass, removing them from childToCase
final ImmutableListMultimap.Builder, DataContainerCodecPrototype>> ambiguousByCaseBuilder =
ImmutableListMultimap.builder();
final Builder, DataContainerCodecPrototype>> unambiguousByCaseBuilder = ImmutableMap.builder();
for (Entry, Set>> e : Multimaps.asMap(childToCase).entrySet()) {
final Set> cases = e.getValue();
if (cases.size() != 1) {
// Sort all possibilities by their FQCN to retain semi-predictable results
final List> list = new ArrayList<>(e.getValue());
list.sort(Comparator.comparing(proto -> proto.getBindingClass().getCanonicalName()));
ambiguousByCaseBuilder.putAll(e.getKey(), list);
} else {
unambiguousByCaseBuilder.put(e.getKey(), cases.iterator().next());
}
}
byCaseChildClass = unambiguousByCaseBuilder.build();
// Setup ambiguous tracking, if needed
ambiguousByCaseChildClass = ambiguousByCaseBuilder.build();
ambiguousByCaseChildWarnings = ambiguousByCaseChildClass.isEmpty() ? ImmutableSet.of()
: ConcurrentHashMap.newKeySet();
final Map, DataContainerCodecPrototype>> bySubstitutionBuilder = new HashMap<>();
/*
* Walks all cases which are not directly instantiated and
* tries to match them to instantiated cases - represent same data as instantiated case,
* only case name or schema path is different. This is required due property of
* binding specification, that if choice is in grouping schema path location is lost,
* and users may use incorrect case class using copy builders.
*/
for (final Class> substitution : potentialSubstitutions) {
search: for (final Entry, DataContainerCodecPrototype>> real : byClassBuilder.entrySet()) {
if (BindingReflections.isSubstitutionFor(substitution, real.getKey())) {
bySubstitutionBuilder.put(substitution, real.getValue());
break search;
}
}
}
byClassBuilder.putAll(bySubstitutionBuilder);
byClass = ImmutableMap.copyOf(byClassBuilder);
}
@SuppressWarnings("unchecked")
@Override
public DataContainerCodecContext streamChild(final Class childClass) {
final DataContainerCodecPrototype> child = byClass.get(childClass);
return (DataContainerCodecContext) childNonNull(child, childClass,
"Supplied class %s is not valid case in %s", childClass, bindingArg()).get();
}
@SuppressWarnings("unchecked")
@Override
public Optional> possibleStreamChild(
final Class childClass) {
final DataContainerCodecPrototype> child = byClass.get(childClass);
if (child != null) {
return Optional.of((DataContainerCodecContext) child.get());
}
return Optional.empty();
}
Iterable> getCaseChildrenClasses() {
return Iterables.concat(byCaseChildClass.keySet(), ambiguousByCaseChildClass.keySet());
}
protected DataContainerCodecPrototype loadCase(final Class> childClass) {
final Optional childSchema = factory().getRuntimeContext().getCaseSchemaDefinition(getSchema(),
childClass);
if (childSchema.isPresent()) {
return DataContainerCodecPrototype.from(childClass, childSchema.get(), factory());
}
LOG.debug("Supplied class {} is not valid case in schema {}", childClass, getSchema());
return null;
}
@Override
public NodeCodecContext yangPathArgumentChild(final YangInstanceIdentifier.PathArgument arg) {
final DataContainerCodecPrototype> cazeProto;
if (arg instanceof YangInstanceIdentifier.NodeIdentifierWithPredicates) {
cazeProto = byYangCaseChild.get(new NodeIdentifier(arg.getNodeType()));
} else {
cazeProto = byYangCaseChild.get(arg);
}
return childNonNull(cazeProto, arg, "Argument %s is not valid child of %s", arg, getSchema()).get()
.yangPathArgumentChild(arg);
}
@SuppressWarnings("unchecked")
@Override
public D deserialize(final NormalizedNode data) {
checkArgument(data instanceof ChoiceNode);
final ChoiceNode casted = (ChoiceNode) data;
final NormalizedNode first = Iterables.getFirst(casted.body(), null);
if (first == null) {
// FIXME: this needs to be sorted out
return null;
}
final DataContainerCodecPrototype> caze = byYangCaseChild.get(first.getIdentifier());
return (D) caze.get().deserialize(data);
}
@Override
protected Object deserializeObject(final NormalizedNode normalizedNode) {
return deserialize(normalizedNode);
}
@Override
public PathArgument deserializePathArgument(final YangInstanceIdentifier.PathArgument arg) {
checkArgument(getDomPathArgument().equals(arg));
return null;
}
@Override
public YangInstanceIdentifier.PathArgument serializePathArgument(final PathArgument arg) {
// FIXME: check for null, since binding container is null.
return getDomPathArgument();
}
DataContainerCodecContext, ?> getCaseByChildClass(final @NonNull Class extends DataObject> type) {
DataContainerCodecPrototype> result = byCaseChildClass.get(type);
if (result == null) {
// We have not found an unambiguous result, try ambiguous ones
final List> inexact = ambiguousByCaseChildClass.get(type);
if (!inexact.isEmpty()) {
result = inexact.get(0);
// Issue a warning, but only once so as not to flood the logs
if (ambiguousByCaseChildWarnings.add(type)) {
LOG.warn("Ambiguous reference {} to child of {} resolved to {}, the first case in {} This mapping "
+ "is not guaranteed to be stable and is subject to variations based on runtime "
+ "circumstances. Please see the stack trace for hints about the source of ambiguity.",
type, bindingArg(), result.getBindingClass(),
Lists.transform(inexact, DataContainerCodecPrototype::getBindingClass), new Throwable());
}
}
}
return childNonNull(result, type, "Class %s is not child of any cases for %s", type, bindingArg()).get();
}
}