data/yang-data-api/src/main/java/org/opendaylight/yangtools/yang/data/api/schema/stream/YangInstanceIdentifierWriter.java

   1 /*
   2  * Copyright (c) 2022 PANTHEON.tech, s.r.o. and others.  All rights reserved.
   3  *
   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
   7  */
   8 package org.opendaylight.yangtools.yang.data.api.schema.stream;
   9
  10 import static java.util.Objects.requireNonNull;
  11
  12 import com.google.common.collect.Collections2;
  13 import com.google.common.collect.ImmutableList;
  14 import com.google.common.collect.ImmutableMap;
  15 import com.google.common.collect.ImmutableSet;
  16 import com.google.common.collect.Iterables;
  17 import java.io.IOException;
  18 import java.util.List;
  19 import javax.xml.transform.dom.DOMSource;
  20 import org.eclipse.jdt.annotation.NonNull;
  21 import org.opendaylight.yangtools.util.ImmutableOffsetMap;
  22 import org.opendaylight.yangtools.yang.common.QName;
  23 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  24 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.AugmentationIdentifier;
  25 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
  26 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
  27 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeWithValue;
  28 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedAnydata;
  29 import org.opendaylight.yangtools.yang.model.api.AnydataSchemaNode;
  30 import org.opendaylight.yangtools.yang.model.api.AnyxmlSchemaNode;
  31 import org.opendaylight.yangtools.yang.model.api.AugmentationSchemaNode;
  32 import org.opendaylight.yangtools.yang.model.api.AugmentationTarget;
  33 import org.opendaylight.yangtools.yang.model.api.ChoiceSchemaNode;
  34 import org.opendaylight.yangtools.yang.model.api.ContainerLike;
  35 import org.opendaylight.yangtools.yang.model.api.DataNodeContainer;
  36 import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
  37 import org.opendaylight.yangtools.yang.model.api.LeafListSchemaNode;
  38 import org.opendaylight.yangtools.yang.model.api.LeafSchemaNode;
  39 import org.opendaylight.yangtools.yang.model.api.ListSchemaNode;
  40
  41 /**
  42  * Utility for emitting a {@link YangInstanceIdentifier} into a {@link NormalizedNodeStreamWriter} as a set of
  43  * {@code startXXXNode} events. An example of usage would be something along the lines of:
  44  * <pre>
  45  *   <code>
  46  *       YangModelContext
  47  *       YangInstanceIdentifier id;
  48  *       var result = new NormalizedNodeResult();
  49  *       try (var writer = ImmutableNormalizedNodeStreamWriter.from(result)) {
  50  *           try (var iidWriter = YangInstanceIdentifierWriter.open(writer, ctx, id)) {
  51  *               // Here the state of 'writer' reflects the nodes in 'id'
  52  *           }
  53  *           // Here the writer is back to its initial state
  54  *       }
  55  *
  56  *       // NormalizedNode result, including the structure created from YangInstanceIdentifier
  57  *       var node = result.getResult();
  58  *   </code>
  59  * </pre>
  60  */
  61 public final class YangInstanceIdentifierWriter implements AutoCloseable {
  62     private NormalizedNodeStreamWriter writer;
  63     private final int endNodeCount;
  64
  65     private YangInstanceIdentifierWriter(final NormalizedNodeStreamWriter writer, final int endNodeCount) {
  66         this.writer = requireNonNull(writer);
  67         this.endNodeCount = endNodeCount;
  68     }
  69
  70     /**
  71      * Open a writer, emitting events in target {@link NormalizedNodeStreamWriter}.
  72      *
  73      * @param writer Writer to enter
  74      * @param root Root container
  75      * @param path Path to enter
  76      * @return A writer instance
  77      * @throws IOException if the path cannot be entered
  78      */
  79     public static @NonNull YangInstanceIdentifierWriter open(final NormalizedNodeStreamWriter writer,
  80             final DataNodeContainer root, final YangInstanceIdentifier path) throws IOException {
  81         final var it = path.getPathArguments().iterator();
  82         if (!it.hasNext()) {
  83             return new YangInstanceIdentifierWriter(writer, 0);
  84         }
  85
  86         // State tracking
  87         int endNodes = 0;
  88         Object parent = root;
  89         boolean reuse = false;
  90         boolean terminal = false;
  91
  92         do {
  93             if (terminal) {
  94                 throw new IOException(parent + " is a terminal node, cannot resolve " + ImmutableList.copyOf(it));
  95             }
  96
  97             final var arg = it.next();
  98             if (arg instanceof AugmentationIdentifier augId) {
  99                 if (!(parent instanceof AugmentationTarget target)) {
 100                     throw new IOException(parent + " does not support augmentations, cannot resolve" + arg);
 101                 }
 102                 if (reuse) {
 103                     throw new IOException(parent + " is expecting a nested item, cannot resolve " + arg);
 104                 }
 105
 106                 parent = enterAugmentation(target, augId);
 107                 writer.startAugmentationNode(augId);
 108             } else if (arg instanceof NodeWithValue<?> nodeId) {
 109                 if (!(parent instanceof LeafListSchemaNode)) {
 110                     throw new IOException(parent + " does not support leaf-list entry " + arg);
 111                 }
 112                 if (!reuse) {
 113                     throw new IOException(parent + " is already at its entry, cannot enter " + arg);
 114                 }
 115
 116                 reuse = false;
 117                 terminal = true;
 118                 writer.startLeafSetEntryNode(nodeId);
 119             } else if (arg instanceof NodeIdentifierWithPredicates nodeId) {
 120                 if (!(parent instanceof ListSchemaNode list)) {
 121                     throw new IOException(parent + " does not support map entry " + arg);
 122                 }
 123                 if (!reuse) {
 124                     throw new IOException(parent + " is already at its entry, cannot enter " + arg);
 125                 }
 126                 if (!list.getQName().equals(nodeId.getNodeType())) {
 127                     throw new IOException(parent + " expects a matching map entry, cannot enter " + arg);
 128                 }
 129
 130                 final var key = list.getKeyDefinition();
 131                 if (key.isEmpty()) {
 132                     throw new IOException(parent + " does not expect map entry " + arg);
 133                 }
 134                 if (key.size() != nodeId.size()) {
 135                     throw new IOException(parent + " expects " + key.size() + " predicates, cannot use " + arg);
 136                 }
 137
 138                 reuse = false;
 139                 writer.startMapEntryNode(normalizePredicates(nodeId, key), 1);
 140             } else if (arg instanceof NodeIdentifier nodeId) {
 141                 if (reuse) {
 142                     if (!(parent instanceof ListSchemaNode list)) {
 143                         throw new IOException(parent + " expects an identifiable entry, cannot enter " + arg);
 144                     }
 145
 146                     if (!list.getKeyDefinition().isEmpty()) {
 147                         throw new IOException(parent + " expects a map entry, cannot enter " + arg);
 148                     }
 149                     if (!list.getQName().equals(nodeId.getNodeType())) {
 150                         throw new IOException(parent + " expects a matching entry, cannot enter " + arg);
 151                     }
 152
 153                     reuse = false;
 154                     writer.startUnkeyedListItem(nodeId, 1);
 155                     endNodes++;
 156                     continue;
 157                 }
 158
 159                 final DataSchemaNode child;
 160                 if (parent instanceof DataNodeContainer container) {
 161                     child = container.dataChildByName(nodeId.getNodeType());
 162                 } else if (parent instanceof ChoiceSchemaNode choice) {
 163                     child = choice.findDataSchemaChild(nodeId.getNodeType()).orElse(null);
 164                 } else {
 165                     throw new IOException("Unhandled parent " + parent + " when looking up " + arg);
 166                 }
 167
 168                 if (child == null) {
 169                     throw new IOException("Failed to find child " + arg + " in parent " + parent);
 170                 }
 171
 172                 // FIXME: check & repair augmentations (brr!)
 173
 174                 if (child instanceof ContainerLike) {
 175                     parent = child;
 176                     writer.startContainerNode(nodeId, 1);
 177                 } else if (child instanceof ListSchemaNode list) {
 178                     parent = child;
 179                     reuse = true;
 180                     if (list.getKeyDefinition().isEmpty()) {
 181                         writer.startUnkeyedList(nodeId, 1);
 182                     } else if (list.isUserOrdered()) {
 183                         writer.startOrderedMapNode(nodeId, 1);
 184                     } else {
 185                         writer.startMapNode(nodeId, 1);
 186                     }
 187                 } else if (child instanceof LeafSchemaNode) {
 188                     parent = child;
 189                     terminal = true;
 190                     writer.startLeafNode(nodeId);
 191                 } else if (child instanceof ChoiceSchemaNode) {
 192                     parent = child;
 193                     writer.startChoiceNode(nodeId, 1);
 194                 } else if (child instanceof LeafListSchemaNode leafList) {
 195                     parent = child;
 196                     reuse = true;
 197                     if (leafList.isUserOrdered()) {
 198                         writer.startOrderedLeafSet(nodeId, 1);
 199                     } else {
 200                         writer.startLeafSet(nodeId, 1);
 201                     }
 202                 } else if (child instanceof AnydataSchemaNode) {
 203                     parent = child;
 204                     terminal = true;
 205                     writer.startAnydataNode(nodeId, NormalizedAnydata.class);
 206                 } else if (child instanceof AnyxmlSchemaNode) {
 207                     parent = child;
 208                     terminal = true;
 209                     writer.startAnyxmlNode(nodeId, DOMSource.class);
 210                 } else {
 211                     throw new IOException("Unhandled child " + child);
 212                 }
 213             } else {
 214                 throw new IOException("Unhandled argument " + arg);
 215             }
 216
 217             endNodes++;
 218         } while (it.hasNext());
 219
 220         return new YangInstanceIdentifierWriter(writer, endNodes);
 221     }
 222
 223     @Override
 224     public void close() throws IOException {
 225         if (writer != null) {
 226             for (int i = 0; i < endNodeCount; ++i) {
 227                 writer.endNode();
 228             }
 229             writer = null;
 230         }
 231     }
 232
 233     private static NodeIdentifierWithPredicates normalizePredicates(final NodeIdentifierWithPredicates input,
 234             final List<QName> key) throws IOException {
 235         if (Iterables.elementsEqual(input.keySet(), key)) {
 236             return input;
 237         }
 238
 239         final var builder = ImmutableMap.<QName, Object>builderWithExpectedSize(key.size());
 240         for (var qname : key) {
 241             final var value = input.getValue(qname);
 242             if (value == null) {
 243                 throw new IOException("Cannot normalize " + input + " to " + key + ", missing value for " + qname);
 244             }
 245             builder.put(qname, value);
 246         }
 247
 248         return NodeIdentifierWithPredicates.of(input.getNodeType(), ImmutableOffsetMap.orderedCopyOf(builder.build()));
 249     }
 250
 251     private static AugmentationSchemaNode enterAugmentation(final AugmentationTarget target,
 252             final AugmentationIdentifier id) throws IOException {
 253         final var augs = target.getAvailableAugmentations();
 254         for (var augment : augs) {
 255             if (id.equals(augmentationIdentifierFrom(augment))) {
 256                 return augment;
 257             }
 258         }
 259         throw new IOException("Cannot find augmentation " + id + " in " + target + ", available: "
 260             + Collections2.transform(augs, YangInstanceIdentifierWriter::augmentationIdentifierFrom));
 261     }
 262
 263     // FIXME: duplicate of data.util.DataSchemaContextNode.augmentationIdentifierFrom()
 264     static @NonNull AugmentationIdentifier augmentationIdentifierFrom(final AugmentationSchemaNode schema) {
 265         return new AugmentationIdentifier(
 266             schema.getChildNodes().stream().map(DataSchemaNode::getQName).collect(ImmutableSet.toImmutableSet()));
 267     }
 268 }