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 import org.opendaylight.yangtools.yang.model.util.EffectiveAugmentationSchema;
  41
  42 /**
  43  * Utility for emitting a {@link YangInstanceIdentifier} into a {@link NormalizedNodeStreamWriter} as a set of
  44  * {@code startXXXNode} events. An example of usage would be something along the lines of:
  45  * <pre>
  46  *   <code>
  47  *       YangModelContext
  48  *       YangInstanceIdentifier id;
  49  *       var result = new NormalizedNodeResult();
  50  *       try (var writer = ImmutableNormalizedNodeStreamWriter.from(result)) {
  51  *           try (var iidWriter = YangInstanceIdentifierWriter.open(writer, ctx, id)) {
  52  *               // Here the state of 'writer' reflects the nodes in 'id'
  53  *           }
  54  *           // Here the writer is back to its initial state
  55  *       }
  56  *
  57  *       // NormalizedNode result, including the structure created from YangInstanceIdentifier
  58  *       var node = result.getResult();
  59  *   </code>
  60  * </pre>
  61  */
  62 public final class YangInstanceIdentifierWriter implements AutoCloseable {
  63     private NormalizedNodeStreamWriter writer;
  64     private final int endNodeCount;
  65
  66     private YangInstanceIdentifierWriter(final NormalizedNodeStreamWriter writer, final int endNodeCount) {
  67         this.writer = requireNonNull(writer);
  68         this.endNodeCount = endNodeCount;
  69     }
  70
  71     /**
  72      * Open a writer, emitting events in target {@link NormalizedNodeStreamWriter}.
  73      *
  74      * @param writer Writer to enter
  75      * @param root Root container
  76      * @param path Path to enter
  77      * @return A writer instance
  78      * @throws IOException if the path cannot be entered
  79      */
  80     public static @NonNull YangInstanceIdentifierWriter open(final NormalizedNodeStreamWriter writer,
  81             final DataNodeContainer root, final YangInstanceIdentifier path) throws IOException {
  82         final var it = path.getPathArguments().iterator();
  83         if (!it.hasNext()) {
  84             return new YangInstanceIdentifierWriter(writer, 0);
  85         }
  86
  87         // State tracking
  88         int endNodes = 0;
  89         Object parent = root;
  90         boolean reuse = false;
  91         boolean terminal = false;
  92
  93         do {
  94             if (terminal) {
  95                 throw new IOException(parent + " is a terminal node, cannot resolve " + ImmutableList.copyOf(it));
  96             }
  97
  98             final var arg = it.next();
  99             if (arg instanceof AugmentationIdentifier augId) {
 100                 if (!(parent instanceof AugmentationTarget target)) {
 101                     throw new IOException(parent + " does not support augmentations, cannot resolve " + arg);
 102                 }
 103                 if (reuse) {
 104                     throw new IOException(parent + " is expecting a nested item, cannot resolve " + arg);
 105                 }
 106
 107                 if (target instanceof DataNodeContainer container) {
 108                     parent = new EffectiveAugmentationSchema(enterAugmentation(target, augId), container);
 109                 } else if (target instanceof ChoiceSchemaNode) {
 110                     throw new IOException(parent + " should not use addressing through " + arg);
 111                 } else {
 112                     throw new IOException("Unhandled parent " + target + " while resolving " + arg);
 113                 }
 114                 writer.startAugmentationNode(augId);
 115             } else if (arg instanceof NodeWithValue<?> nodeId) {
 116                 if (!(parent instanceof LeafListSchemaNode)) {
 117                     throw new IOException(parent + " does not support leaf-list entry " + arg);
 118                 }
 119                 if (!reuse) {
 120                     throw new IOException(parent + " is already at its entry, cannot enter " + arg);
 121                 }
 122
 123                 reuse = false;
 124                 terminal = true;
 125                 writer.startLeafSetEntryNode(nodeId);
 126             } else if (arg instanceof NodeIdentifierWithPredicates nodeId) {
 127                 if (!(parent instanceof ListSchemaNode list)) {
 128                     throw new IOException(parent + " does not support map entry " + arg);
 129                 }
 130                 if (!reuse) {
 131                     throw new IOException(parent + " is already at its entry, cannot enter " + arg);
 132                 }
 133                 if (!list.getQName().equals(nodeId.getNodeType())) {
 134                     throw new IOException(parent + " expects a matching map entry, cannot enter " + arg);
 135                 }
 136
 137                 final var key = list.getKeyDefinition();
 138                 if (key.isEmpty()) {
 139                     throw new IOException(parent + " does not expect map entry " + arg);
 140                 }
 141                 if (key.size() != nodeId.size()) {
 142                     throw new IOException(parent + " expects " + key.size() + " predicates, cannot use " + arg);
 143                 }
 144
 145                 reuse = false;
 146                 writer.startMapEntryNode(normalizePredicates(nodeId, key), 1);
 147             } else if (arg instanceof NodeIdentifier nodeId) {
 148                 if (reuse) {
 149                     if (!(parent instanceof ListSchemaNode list)) {
 150                         throw new IOException(parent + " expects an identifiable entry, cannot enter " + arg);
 151                     }
 152
 153                     if (!list.getKeyDefinition().isEmpty()) {
 154                         throw new IOException(parent + " expects a map entry, cannot enter " + arg);
 155                     }
 156                     if (!list.getQName().equals(nodeId.getNodeType())) {
 157                         throw new IOException(parent + " expects a matching entry, cannot enter " + arg);
 158                     }
 159
 160                     reuse = false;
 161                     writer.startUnkeyedListItem(nodeId, 1);
 162                     endNodes++;
 163                     continue;
 164                 }
 165
 166                 final DataSchemaNode child;
 167                 if (parent instanceof DataNodeContainer container) {
 168                     child = container.dataChildByName(nodeId.getNodeType());
 169                 } else if (parent instanceof ChoiceSchemaNode choice) {
 170                     child = choice.findDataSchemaChild(nodeId.getNodeType()).orElse(null);
 171                 } else {
 172                     throw new IOException("Unhandled parent " + parent + " when looking up " + arg);
 173                 }
 174
 175                 if (child == null) {
 176                     throw new IOException("Failed to find child " + arg + " in parent " + parent);
 177                 }
 178
 179                 // FIXME: check & repair augmentations (brr!)
 180
 181                 if (child instanceof ContainerLike) {
 182                     parent = child;
 183                     writer.startContainerNode(nodeId, 1);
 184                 } else if (child instanceof ListSchemaNode list) {
 185                     parent = child;
 186                     reuse = true;
 187                     if (list.getKeyDefinition().isEmpty()) {
 188                         writer.startUnkeyedList(nodeId, 1);
 189                     } else if (list.isUserOrdered()) {
 190                         writer.startOrderedMapNode(nodeId, 1);
 191                     } else {
 192                         writer.startMapNode(nodeId, 1);
 193                     }
 194                 } else if (child instanceof LeafSchemaNode) {
 195                     parent = child;
 196                     terminal = true;
 197                     writer.startLeafNode(nodeId);
 198                 } else if (child instanceof ChoiceSchemaNode) {
 199                     parent = child;
 200                     writer.startChoiceNode(nodeId, 1);
 201                 } else if (child instanceof LeafListSchemaNode leafList) {
 202                     parent = child;
 203                     reuse = true;
 204                     if (leafList.isUserOrdered()) {
 205                         writer.startOrderedLeafSet(nodeId, 1);
 206                     } else {
 207                         writer.startLeafSet(nodeId, 1);
 208                     }
 209                 } else if (child instanceof AnydataSchemaNode) {
 210                     parent = child;
 211                     terminal = true;
 212                     writer.startAnydataNode(nodeId, NormalizedAnydata.class);
 213                 } else if (child instanceof AnyxmlSchemaNode) {
 214                     parent = child;
 215                     terminal = true;
 216                     writer.startAnyxmlNode(nodeId, DOMSource.class);
 217                 } else {
 218                     throw new IOException("Unhandled child " + child);
 219                 }
 220             } else {
 221                 throw new IOException("Unhandled argument " + arg);
 222             }
 223
 224             endNodes++;
 225         } while (it.hasNext());
 226
 227         return new YangInstanceIdentifierWriter(writer, endNodes);
 228     }
 229
 230     @Override
 231     public void close() throws IOException {
 232         if (writer != null) {
 233             for (int i = 0; i < endNodeCount; ++i) {
 234                 writer.endNode();
 235             }
 236             writer = null;
 237         }
 238     }
 239
 240     private static NodeIdentifierWithPredicates normalizePredicates(final NodeIdentifierWithPredicates input,
 241             final List<QName> key) throws IOException {
 242         if (Iterables.elementsEqual(input.keySet(), key)) {
 243             return input;
 244         }
 245
 246         final var builder = ImmutableMap.<QName, Object>builderWithExpectedSize(key.size());
 247         for (var qname : key) {
 248             final var value = input.getValue(qname);
 249             if (value == null) {
 250                 throw new IOException("Cannot normalize " + input + " to " + key + ", missing value for " + qname);
 251             }
 252             builder.put(qname, value);
 253         }
 254
 255         return NodeIdentifierWithPredicates.of(input.getNodeType(), ImmutableOffsetMap.orderedCopyOf(builder.build()));
 256     }
 257
 258     private static AugmentationSchemaNode enterAugmentation(final AugmentationTarget target,
 259             final AugmentationIdentifier id) throws IOException {
 260         final var augs = target.getAvailableAugmentations();
 261         for (var augment : augs) {
 262             if (id.equals(augmentationIdentifierFrom(augment))) {
 263                 return augment;
 264             }
 265         }
 266         throw new IOException("Cannot find augmentation " + id + " in " + target + ", available: "
 267             + Collections2.transform(augs, YangInstanceIdentifierWriter::augmentationIdentifierFrom));
 268     }
 269
 270     // FIXME: duplicate of data.util.DataSchemaContextNode.augmentationIdentifierFrom()
 271     static @NonNull AugmentationIdentifier augmentationIdentifierFrom(final AugmentationSchemaNode schema) {
 272         return new AugmentationIdentifier(
 273             schema.getChildNodes().stream().map(DataSchemaNode::getQName).collect(ImmutableSet.toImmutableSet()));
 274     }
 275 }