restconf/restconf-nb/src/main/java/org/opendaylight/restconf/server/spi/NormalizedFormattableBody.java

   1 /*
   2  * Copyright (c) 2024 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.restconf.server.spi;
   9
  10 import static java.util.Objects.requireNonNull;
  11
  12 import com.google.common.base.MoreObjects.ToStringHelper;
  13 import com.google.common.base.VerifyException;
  14 import com.google.gson.stream.JsonWriter;
  15 import java.io.IOException;
  16 import java.io.OutputStream;
  17 import javax.xml.stream.XMLStreamException;
  18 import javax.xml.stream.XMLStreamWriter;
  19 import org.eclipse.jdt.annotation.NonNullByDefault;
  20 import org.opendaylight.restconf.api.FormattableBody;
  21 import org.opendaylight.restconf.api.query.PrettyPrintParam;
  22 import org.opendaylight.restconf.server.api.DatabindContext;
  23 import org.opendaylight.restconf.server.api.DatabindFormattableBody;
  24 import org.opendaylight.restconf.server.api.DatabindPath.Data;
  25 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
  26 import org.opendaylight.yangtools.yang.data.api.schema.LeafSetEntryNode;
  27 import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
  28 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  29 import org.opendaylight.yangtools.yang.data.api.schema.UnkeyedListEntryNode;
  30 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  31 import org.opendaylight.yangtools.yang.data.codec.gson.JSONCodecFactory;
  32 import org.opendaylight.yangtools.yang.data.codec.xml.XmlCodecFactory;
  33 import org.opendaylight.yangtools.yang.model.util.SchemaInferenceStack.Inference;
  34
  35 /**
  36  * A {@link FormattableBody} representing a data resource.
  37  */
  38 @NonNullByDefault
  39 public abstract sealed class NormalizedFormattableBody<N extends NormalizedNode> extends DatabindFormattableBody
  40         permits DataFormattableBody, RootFormattableBody {
  41     private final NormalizedNodeWriterFactory writerFactory;
  42     private final N data;
  43
  44     NormalizedFormattableBody(final DatabindContext databind, final NormalizedNodeWriterFactory writerFactory,
  45             final N data) {
  46         super(databind);
  47         this.writerFactory = requireNonNull(writerFactory);
  48         this.data = requireNonNull(data);
  49     }
  50
  51     public static NormalizedFormattableBody<?> of(final Data path, final NormalizedNode data,
  52             final NormalizedNodeWriterFactory writerFactory) {
  53         final var inference = path.inference();
  54         if (inference.isEmpty()) {
  55             // Read of the entire /data resource
  56             if (data instanceof ContainerNode container) {
  57                 return new RootFormattableBody(path.databind(), writerFactory, container);
  58             }
  59             throw new VerifyException("Unexpected root data contract " + data.contract());
  60         }
  61
  62         // Read of a sub-resource. We need to adjust the inference to point to the NormalizedNode parent of the node
  63         // being output.
  64         final Inference parentInference;
  65         if (data instanceof MapEntryNode || data instanceof LeafSetEntryNode || data instanceof UnkeyedListEntryNode) {
  66             parentInference = inference;
  67         } else {
  68             final var stack = inference.toSchemaInferenceStack();
  69             stack.exitToDataTree();
  70             parentInference = stack.toInference();
  71         }
  72
  73         return new DataFormattableBody<>(path.databind(), parentInference, data, writerFactory);
  74     }
  75
  76     /**
  77      * Return data.
  78      *
  79      * @return data
  80      */
  81     public final N data() {
  82         return data;
  83     }
  84
  85     @Override
  86     protected final void formatToJSON(final DatabindContext databind, final PrettyPrintParam prettyPrint,
  87             final OutputStream out) throws IOException {
  88         try (var writer = FormattableBodySupport.createJsonWriter(out, prettyPrint)) {
  89             formatToJSON(databind.jsonCodecs(), data, writer);
  90         }
  91     }
  92
  93     protected abstract void formatToJSON(JSONCodecFactory codecs, N data, JsonWriter writer) throws IOException;
  94
  95     @Override
  96     protected final void formatToXML(final DatabindContext databind, final PrettyPrintParam prettyPrint,
  97             final OutputStream out) throws IOException {
  98         final var writer = FormattableBodySupport.createXmlWriter(out, prettyPrint);
  99         try {
 100             formatToXML(databind.xmlCodecs(), data, writer);
 101             writer.close();
 102         } catch (XMLStreamException e) {
 103             throw new IOException("Failed to write data", e);
 104         }
 105     }
 106
 107     protected abstract void formatToXML(XmlCodecFactory codecs, N data, XMLStreamWriter writer)
 108         throws IOException, XMLStreamException;
 109
 110     protected final NormalizedNodeWriter newWriter(final NormalizedNodeStreamWriter streamWriter) {
 111         return writerFactory.newWriter(streamWriter);
 112     }
 113
 114     final void writeTo(final NormalizedNode toWrite, final NormalizedNodeStreamWriter streamWriter)
 115             throws IOException {
 116         try (var writer = newWriter(streamWriter)) {
 117             writer.write(toWrite);
 118         }
 119     }
 120
 121     @Override
 122     protected ToStringHelper addToStringAttributes(final ToStringHelper helper) {
 123         return helper.add("body", data.prettyTree());
 124     }
 125
 126
 127 }