cps-service/src/main/java/org/onap/cps/utils/YangUtils.java

   1 /*
   2  *  ============LICENSE_START=======================================================
   3  *  Copyright (C) 2020-2022 Nordix Foundation
   4  *  Modifications Copyright (C) 2021 Bell Canada.
   5  *  Modifications Copyright (C) 2021 Pantheon.tech
   6  *  Modifications Copyright (C) 2022 TechMahindra Ltd.
   7  *  ================================================================================
   8  *  Licensed under the Apache License, Version 2.0 (the "License");
   9  *  you may not use this file except in compliance with the License.
  10  *  You may obtain a copy of the License at
  11  *
  12  *        http://www.apache.org/licenses/LICENSE-2.0
  13  *
  14  *  Unless required by applicable law or agreed to in writing, software
  15  *  distributed under the License is distributed on an "AS IS" BASIS,
  16  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  17  *  See the License for the specific language governing permissions and
  18  *  limitations under the License.
  19  *
  20  *  SPDX-License-Identifier: Apache-2.0
  21  *  ============LICENSE_END=========================================================
  22  */
  23
  24 package org.onap.cps.utils;
  25
  26 import com.google.gson.JsonSyntaxException;
  27 import com.google.gson.stream.JsonReader;
  28 import java.io.IOException;
  29 import java.io.StringReader;
  30 import java.util.ArrayList;
  31 import java.util.Arrays;
  32 import java.util.Collection;
  33 import java.util.Collections;
  34 import java.util.List;
  35 import java.util.Optional;
  36 import java.util.stream.Collectors;
  37 import lombok.AccessLevel;
  38 import lombok.NoArgsConstructor;
  39 import lombok.extern.slf4j.Slf4j;
  40 import org.onap.cps.spi.exceptions.DataValidationException;
  41 import org.opendaylight.yangtools.yang.common.QName;
  42 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  43 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
  44 import org.opendaylight.yangtools.yang.data.api.schema.builder.DataContainerNodeBuilder;
  45 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  46 import org.opendaylight.yangtools.yang.data.codec.gson.JSONCodecFactory;
  47 import org.opendaylight.yangtools.yang.data.codec.gson.JSONCodecFactorySupplier;
  48 import org.opendaylight.yangtools.yang.data.codec.gson.JsonParserStream;
  49 import org.opendaylight.yangtools.yang.data.impl.schema.Builders;
  50 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNormalizedNodeStreamWriter;
  51 import org.opendaylight.yangtools.yang.model.api.DataNodeContainer;
  52 import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
  53 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
  54 import org.opendaylight.yangtools.yang.model.api.EffectiveStatementInference;
  55 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  56 import org.opendaylight.yangtools.yang.model.api.stmt.SchemaNodeIdentifier;
  57 import org.opendaylight.yangtools.yang.model.util.SchemaInferenceStack;
  58
  59 @Slf4j
  60 @NoArgsConstructor(access = AccessLevel.PRIVATE)
  61 public class YangUtils {
  62
  63     private static final String XPATH_DELIMITER_REGEX = "\\/";
  64     private static final String XPATH_NODE_KEY_ATTRIBUTES_REGEX = "\\[.*?\\]";
  65
  66     /**
  67      * Parses jsonData into Collection of NormalizedNode according to given schema context.
  68      *
  69      * @param jsonData      json data as string
  70      * @param schemaContext schema context describing associated data model
  71      * @return the Collection of NormalizedNode object
  72      */
  73     public static ContainerNode parseJsonData(final String jsonData, final SchemaContext schemaContext) {
  74         return parseJsonData(jsonData, schemaContext, Optional.empty());
  75     }
  76
  77     /**
  78      * Parses jsonData into Collection of NormalizedNode according to given schema context.
  79      *
  80      * @param jsonData        json data fragment as string
  81      * @param schemaContext   schema context describing associated data model
  82      * @param parentNodeXpath the xpath referencing the parent node current data fragment belong to
  83      * @return the NormalizedNode object
  84      */
  85     public static ContainerNode parseJsonData(final String jsonData, final SchemaContext schemaContext,
  86         final String parentNodeXpath) {
  87         final Collection<QName> dataSchemaNodeIdentifiers =
  88                 getDataSchemaNodeIdentifiersByXpath(parentNodeXpath, schemaContext);
  89         return parseJsonData(jsonData, schemaContext, Optional.of(dataSchemaNodeIdentifiers));
  90     }
  91
  92     private static ContainerNode parseJsonData(final String jsonData, final SchemaContext schemaContext,
  93         final Optional<Collection<QName>> dataSchemaNodeIdentifiers) {
  94         final JSONCodecFactory jsonCodecFactory = JSONCodecFactorySupplier.DRAFT_LHOTKA_NETMOD_YANG_JSON_02
  95             .getShared((EffectiveModelContext) schemaContext);
  96         final DataContainerNodeBuilder<YangInstanceIdentifier.NodeIdentifier, ContainerNode> dataContainerNodeBuilder =
  97                 Builders.containerBuilder()
  98                         .withNodeIdentifier(new YangInstanceIdentifier.NodeIdentifier(schemaContext.getQName()));
  99         final NormalizedNodeStreamWriter normalizedNodeStreamWriter = ImmutableNormalizedNodeStreamWriter
 100                 .from(dataContainerNodeBuilder);
 101         final JsonReader jsonReader = new JsonReader(new StringReader(jsonData));
 102         final JsonParserStream jsonParserStream;
 103
 104         if (dataSchemaNodeIdentifiers.isPresent()) {
 105             final EffectiveModelContext effectiveModelContext = ((EffectiveModelContext) schemaContext);
 106             final EffectiveStatementInference effectiveStatementInference =
 107                     SchemaInferenceStack.of(effectiveModelContext,
 108                     SchemaNodeIdentifier.Absolute.of(dataSchemaNodeIdentifiers.get())).toInference();
 109             jsonParserStream =
 110                     JsonParserStream.create(normalizedNodeStreamWriter, jsonCodecFactory, effectiveStatementInference);
 111         } else {
 112             jsonParserStream = JsonParserStream.create(normalizedNodeStreamWriter, jsonCodecFactory);
 113         }
 114
 115         try {
 116             jsonParserStream.parse(jsonReader);
 117             jsonParserStream.close();
 118         } catch (final JsonSyntaxException exception) {
 119             throw new DataValidationException(
 120                 "Failed to parse json data: " + jsonData, exception.getMessage(), exception);
 121         } catch (final IOException | IllegalStateException illegalStateException) {
 122             throw new DataValidationException(
 123                 "Failed to parse json data. Unsupported xpath or json data:" + jsonData, illegalStateException
 124                 .getMessage(), illegalStateException);
 125         }
 126         return dataContainerNodeBuilder.build();
 127     }
 128
 129     /**
 130      * Create an xpath form a Yang Tools NodeIdentifier (i.e. PathArgument).
 131      *
 132      * @param nodeIdentifier the NodeIdentifier
 133      * @return an xpath
 134      */
 135     public static String buildXpath(final YangInstanceIdentifier.PathArgument nodeIdentifier) {
 136         final StringBuilder xpathBuilder = new StringBuilder();
 137         xpathBuilder.append("/").append(nodeIdentifier.getNodeType().getLocalName());
 138
 139         if (nodeIdentifier instanceof YangInstanceIdentifier.NodeIdentifierWithPredicates) {
 140             xpathBuilder.append(getKeyAttributesStatement(
 141                 (YangInstanceIdentifier.NodeIdentifierWithPredicates) nodeIdentifier));
 142         }
 143         return xpathBuilder.toString();
 144     }
 145
 146
 147     private static String getKeyAttributesStatement(
 148         final YangInstanceIdentifier.NodeIdentifierWithPredicates nodeIdentifier) {
 149         final List<String> keyAttributes = nodeIdentifier.entrySet().stream().map(
 150             entry -> {
 151                 final String name = entry.getKey().getLocalName();
 152                 final String value = String.valueOf(entry.getValue()).replace("'", "\\'");
 153                 return String.format("@%s='%s'", name, value);
 154             }
 155         ).collect(Collectors.toList());
 156
 157         if (keyAttributes.isEmpty()) {
 158             return "";
 159         } else {
 160             Collections.sort(keyAttributes);
 161             return "[" + String.join(" and ", keyAttributes) + "]";
 162         }
 163     }
 164
 165     private static Collection<QName> getDataSchemaNodeIdentifiersByXpath(final String parentNodeXpath,
 166                                                                       final SchemaContext schemaContext) {
 167         final String[] xpathNodeIdSequence = xpathToNodeIdSequence(parentNodeXpath);
 168         return findDataSchemaNodeIdentifiersByXpathNodeIdSequence(xpathNodeIdSequence, schemaContext.getChildNodes(),
 169                 new ArrayList<>());
 170     }
 171
 172     private static String[] xpathToNodeIdSequence(final String xpath) {
 173         final String[] xpathNodeIdSequence = Arrays.stream(xpath
 174                         .replaceAll(XPATH_NODE_KEY_ATTRIBUTES_REGEX, "")
 175                         .split(XPATH_DELIMITER_REGEX))
 176                 .filter(identifier -> !identifier.isEmpty())
 177                 .toArray(String[]::new);
 178         if (xpathNodeIdSequence.length < 1) {
 179             throw new DataValidationException("Invalid xpath.", "Xpath contains no node identifiers.");
 180         }
 181         return xpathNodeIdSequence;
 182     }
 183
 184     private static Collection<QName> findDataSchemaNodeIdentifiersByXpathNodeIdSequence(
 185             final String[] xpathNodeIdSequence,
 186             final Collection<? extends DataSchemaNode> dataSchemaNodes,
 187             final Collection<QName> dataSchemaNodeIdentifiers) {
 188         final String currentXpathNodeId = xpathNodeIdSequence[0];
 189         final DataSchemaNode currentDataSchemaNode = dataSchemaNodes.stream()
 190             .filter(dataSchemaNode -> currentXpathNodeId.equals(dataSchemaNode.getQName().getLocalName()))
 191             .findFirst().orElseThrow(() -> schemaNodeNotFoundException(currentXpathNodeId));
 192         dataSchemaNodeIdentifiers.add(currentDataSchemaNode.getQName());
 193         if (xpathNodeIdSequence.length <= 1) {
 194             return dataSchemaNodeIdentifiers;
 195         }
 196         if (currentDataSchemaNode instanceof DataNodeContainer) {
 197             return findDataSchemaNodeIdentifiersByXpathNodeIdSequence(
 198                 getNextLevelXpathNodeIdSequence(xpathNodeIdSequence),
 199                     ((DataNodeContainer) currentDataSchemaNode).getChildNodes(),
 200                     dataSchemaNodeIdentifiers);
 201         }
 202         throw schemaNodeNotFoundException(xpathNodeIdSequence[1]);
 203     }
 204
 205     private static String[] getNextLevelXpathNodeIdSequence(final String[] xpathNodeIdSequence) {
 206         final String[] nextXpathNodeIdSequence = new String[xpathNodeIdSequence.length - 1];
 207         System.arraycopy(xpathNodeIdSequence, 1, nextXpathNodeIdSequence, 0, nextXpathNodeIdSequence.length);
 208         return nextXpathNodeIdSequence;
 209     }
 210
 211     private static DataValidationException schemaNodeNotFoundException(final String schemaNodeIdentifier) {
 212         return new DataValidationException("Invalid xpath.",
 213             String.format("No schema node was found for xpath identifier '%s'.", schemaNodeIdentifier));
 214     }
 215 }