restconf/restconf-nb/src/main/java/org/opendaylight/restconf/server/api/AbstractBody.java

   1 /*
   2  * Copyright (c) 2023 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.api;
   9
  10 import static java.util.Objects.requireNonNull;
  11
  12 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
  13 import java.io.IOException;
  14 import java.io.InputStream;
  15 import java.lang.invoke.MethodHandles;
  16 import java.lang.invoke.VarHandle;
  17 import org.eclipse.jdt.annotation.NonNull;
  18 import org.eclipse.jdt.annotation.Nullable;
  19 import org.opendaylight.restconf.common.errors.RestconfDocumentedException;
  20 import org.opendaylight.restconf.common.errors.RestconfError;
  21 import org.opendaylight.yangtools.yang.data.api.YangNetconfError;
  22 import org.opendaylight.yangtools.yang.data.api.YangNetconfErrorAware;
  23 import org.slf4j.Logger;
  24 import org.slf4j.LoggerFactory;
  25
  26 /**
  27  * An abstract request body backed by an {@link InputStream}.
  28  */
  29 public abstract sealed class AbstractBody implements AutoCloseable
  30         permits ChildBody, DataPostBody, OperationInputBody, PatchBody, ResourceBody {
  31     private static final Logger LOG = LoggerFactory.getLogger(AbstractBody.class);
  32
  33     private static final VarHandle INPUT_STREAM;
  34
  35     static {
  36         try {
  37             INPUT_STREAM = MethodHandles.lookup().findVarHandle(AbstractBody.class, "inputStream", InputStream.class);
  38         } catch (NoSuchFieldException | IllegalAccessException e) {
  39             throw new ExceptionInInitializerError(e);
  40         }
  41     }
  42
  43     @SuppressWarnings("unused")
  44     @SuppressFBWarnings(value = "URF_UNREAD_FIELD", justification = "https://github.com/spotbugs/spotbugs/issues/2749")
  45     private volatile InputStream inputStream;
  46
  47     AbstractBody(final InputStream inputStream) {
  48         this.inputStream = requireNonNull(inputStream);
  49     }
  50
  51     @Override
  52     public final void close() {
  53         final var is = getStream();
  54         if (is != null) {
  55             try {
  56                 is.close();
  57             } catch (IOException e) {
  58                 LOG.info("Failed to close input", e);
  59             }
  60         }
  61     }
  62
  63     final @NonNull InputStream acquireStream() {
  64         final var is = getStream();
  65         if (is == null) {
  66             throw new IllegalStateException("Input stream has already been consumed");
  67         }
  68         return is;
  69     }
  70
  71
  72     /**
  73      * Throw a {@link RestconfDocumentedException} if the specified exception has a {@link YangNetconfError} attachment.
  74      *
  75      * @param cause Proposed cause of a RestconfDocumentedException
  76      */
  77     static void throwIfYangError(final Exception cause) {
  78         if (cause instanceof YangNetconfErrorAware infoAware) {
  79             throw new RestconfDocumentedException(cause, infoAware.getNetconfErrors().stream()
  80                 .map(error -> new RestconfError(error.type(), error.tag(), error.message(), error.appTag(),
  81                     // FIXME: pass down error info
  82                     null, error.path()))
  83                 .toList());
  84         }
  85     }
  86
  87     private @Nullable InputStream getStream() {
  88         return (InputStream) INPUT_STREAM.getAndSet(this, null);
  89     }
  90 }