2 * Copyright (c) 2020 PANTHEON.tech, s.r.o. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.restconf.nb.rfc8040.streams.listeners;
10 import static com.google.common.base.Verify.verifyNotNull;
11 import static java.util.Objects.requireNonNull;
13 import java.util.ArrayDeque;
14 import java.util.ArrayList;
15 import java.util.Collection;
16 import java.util.Comparator;
17 import java.util.Deque;
18 import org.eclipse.jdt.annotation.Nullable;
19 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
20 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
21 import org.opendaylight.yangtools.yang.data.api.schema.LeafNode;
22 import org.opendaylight.yangtools.yang.data.api.schema.LeafSetNode;
23 import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
24 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
25 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
26 import org.opendaylight.yangtools.yang.data.tree.api.DataTreeCandidate;
27 import org.opendaylight.yangtools.yang.data.tree.api.DataTreeCandidateNode;
28 import org.opendaylight.yangtools.yang.data.tree.api.ModificationType;
29 import org.opendaylight.yangtools.yang.data.util.DataSchemaContext;
30 import org.opendaylight.yangtools.yang.data.util.DataSchemaContextTree;
31 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
32 import org.opendaylight.yangtools.yang.model.util.SchemaInferenceStack;
33 import org.opendaylight.yangtools.yang.model.util.SchemaInferenceStack.Inference;
34 import org.slf4j.Logger;
35 import org.slf4j.LoggerFactory;
37 abstract class AbstractWebsocketSerializer<T extends Exception> {
38 private static final Logger LOG = LoggerFactory.getLogger(AbstractWebsocketSerializer.class);
40 private final EffectiveModelContext context;
42 AbstractWebsocketSerializer(final EffectiveModelContext context) {
43 this.context = requireNonNull(context);
46 public final boolean serialize(final DataTreeCandidate candidate, final boolean leafNodesOnly,
47 final boolean skipData, final boolean changedLeafNodesOnly) throws T {
48 if (leafNodesOnly || changedLeafNodesOnly) {
49 final var path = new ArrayDeque<PathArgument>();
50 path.addAll(candidate.getRootPath().getPathArguments());
51 return serializeLeafNodesOnly(path, candidate.getRootNode(), skipData, changedLeafNodesOnly);
54 serializeData(candidate.getRootPath().getPathArguments(), candidate.getRootNode(), skipData);
58 final boolean serializeLeafNodesOnly(final Deque<PathArgument> path, final DataTreeCandidateNode candidate,
59 final boolean skipData, final boolean changedLeafNodesOnly) throws T {
60 final var node = switch (candidate.modificationType()) {
61 case SUBTREE_MODIFIED, APPEARED -> candidate.getDataAfter();
62 case DELETE, DISAPPEARED -> candidate.getDataBefore();
63 case WRITE -> changedLeafNodesOnly && isNotUpdate(candidate) ? null : candidate.getDataAfter();
65 // no reason to do anything with an unmodified node
66 LOG.debug("DataTreeCandidate for a notification is unmodified, not serializing leaves. Candidate: {}",
75 if (node instanceof LeafNode || node instanceof LeafSetNode) {
76 serializeData(path, candidate, skipData);
80 // Retain a modicum of sanity here: children may come from different namespaces. Report children from the same
81 // namespace first, holding others back. Once that is done, sort the remaining children by their PathArgument
82 // and report them in that order.
83 final var myNamespace = node.name().getNodeType().getModule();
84 final var heldBack = new ArrayList<DataTreeCandidateNode>();
86 for (var childNode : candidate.childNodes()) {
87 final var childName = childNode.name();
88 if (myNamespace.equals(childName.getNodeType().getModule())) {
89 ret |= serializeChild(path, childNode, skipData, changedLeafNodesOnly);
91 heldBack.add(childNode);
94 if (!heldBack.isEmpty()) {
95 // This is not exactly nice, as we really should be using schema definition order, but we do not have it
96 // available here, so we fall back to the next best thing.
97 heldBack.sort(Comparator.comparing(DataTreeCandidateNode::name));
98 for (var childNode : heldBack) {
99 ret |= serializeChild(path, childNode, skipData, changedLeafNodesOnly);
105 private boolean serializeChild(final Deque<PathArgument> path, final DataTreeCandidateNode childNode,
106 final boolean skipData, final boolean changedLeafNodesOnly) throws T {
108 path.add(childNode.name());
109 ret = serializeLeafNodesOnly(path, childNode, skipData, changedLeafNodesOnly);
114 private void serializeData(final Collection<PathArgument> dataPath, final DataTreeCandidateNode candidate,
115 final boolean skipData) throws T {
116 var stack = SchemaInferenceStack.of(context);
117 DataSchemaContext current = DataSchemaContextTree.from(context).getRoot();
118 for (var arg : dataPath) {
119 final var next = current instanceof DataSchemaContext.Composite composite ? composite.enterChild(stack, arg)
121 current = verifyNotNull(next, "Failed to resolve %s: cannot find %s in %s", dataPath, arg, current);
124 // Exit to parent if needed
125 if (!stack.isEmpty()) {
129 serializeData(stack.toInference(), dataPath, candidate, skipData);
132 abstract void serializeData(Inference parent, Collection<PathArgument> dataPath, DataTreeCandidateNode candidate,
133 boolean skipData) throws T;
135 private static boolean isNotUpdate(final DataTreeCandidateNode node) {
136 final var before = node.dataBefore();
137 final var after = node.dataAfter();
139 return before != null && after != null && before.body().equals(after.body());
142 abstract void serializePath(Collection<PathArgument> pathArguments) throws T;
144 abstract void serializeOperation(DataTreeCandidateNode candidate) throws T;
146 static final @Nullable NormalizedNode getDataAfter(final DataTreeCandidateNode candidate) {
147 final var data = candidate.dataAfter();
148 if (data instanceof MapEntryNode mapEntry) {
149 return ImmutableNodes.mapNodeBuilder(data.name().getNodeType()).withChild(mapEntry).build();
154 static final String convertPath(final Collection<PathArgument> path) {
155 final StringBuilder pathBuilder = new StringBuilder();
157 for (var pathArgument : path) {
158 pathBuilder.append('/');
159 pathBuilder.append(pathArgument.getNodeType().getNamespace().toString().replace(':', '-'));
160 pathBuilder.append(':');
161 pathBuilder.append(pathArgument.getNodeType().getLocalName());
163 if (pathArgument instanceof NodeIdentifierWithPredicates nip) {
164 pathBuilder.append("[");
165 for (var key : nip.entrySet()) {
166 pathBuilder.append(key.getKey().getNamespace().toString().replace(':', '-'));
167 pathBuilder.append(':');
168 pathBuilder.append(key.getKey().getLocalName());
169 pathBuilder.append("='");
170 pathBuilder.append(key.getValue().toString());
171 pathBuilder.append('\'');
173 pathBuilder.append(']');
177 return pathBuilder.toString();
180 static final String modificationTypeToOperation(final DataTreeCandidateNode candidate,
181 final ModificationType modificationType) {
182 return switch (modificationType) {
183 case APPEARED, SUBTREE_MODIFIED, WRITE -> candidate.dataBefore() != null ? "updated" : "created";
184 case DELETE, DISAPPEARED -> "deleted";
186 // shouldn't ever happen since the root of a modification is only triggered by some event
187 LOG.warn("DataTreeCandidate for a notification is unmodified. Candidate: {}", candidate);