restconf/restconf-openapi/src/main/java/org/opendaylight/restconf/openapi/impl/OpenApiInputStream.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.openapi.impl;
   9
  10 import com.fasterxml.jackson.core.JsonFactoryBuilder;
  11 import com.fasterxml.jackson.core.JsonGenerator;
  12 import java.io.ByteArrayInputStream;
  13 import java.io.ByteArrayOutputStream;
  14 import java.io.IOException;
  15 import java.io.InputStream;
  16 import java.io.InputStreamReader;
  17 import java.io.Reader;
  18 import java.nio.charset.StandardCharsets;
  19 import java.util.ArrayDeque;
  20 import java.util.Collection;
  21 import java.util.Deque;
  22 import java.util.List;
  23 import java.util.Map;
  24 import org.opendaylight.restconf.openapi.jaxrs.OpenApiBodyWriter;
  25 import org.opendaylight.restconf.openapi.model.InfoEntity;
  26 import org.opendaylight.restconf.openapi.model.OpenApiVersionEntity;
  27 import org.opendaylight.restconf.openapi.model.SecurityEntity;
  28 import org.opendaylight.restconf.openapi.model.ServerEntity;
  29 import org.opendaylight.restconf.openapi.model.ServersEntity;
  30 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
  31 import org.opendaylight.yangtools.yang.model.api.Module;
  32
  33 public final class OpenApiInputStream extends InputStream {
  34     private final ByteArrayOutputStream stream = new ByteArrayOutputStream();
  35     private final JsonGenerator generator = new JsonFactoryBuilder().build().createGenerator(stream);
  36     private final Deque<InputStream> stack = new ArrayDeque<>();
  37
  38     private Reader reader;
  39
  40     private boolean eof;
  41
  42     public OpenApiInputStream(final EffectiveModelContext context, final String title, final String url,
  43             final List<Map<String, List<String>>> security, final String deviceName, final String urlPrefix,
  44             final boolean isForSingleModule, final boolean includeDataStore, final Collection<? extends Module> modules)
  45             throws IOException {
  46         final OpenApiBodyWriter writer = new OpenApiBodyWriter(generator, stream);
  47         stack.add(new OpenApiVersionStream(new OpenApiVersionEntity(), writer));
  48         stack.add(new InfoStream(new InfoEntity(title), writer));
  49         stack.add(new ServersStream(new ServersEntity(List.of(new ServerEntity(url))), writer));
  50         stack.add(new PathsStream(context, writer, generator, stream, deviceName, urlPrefix, isForSingleModule,
  51             includeDataStore, modules.iterator()));
  52         stack.add(new SchemasStream(context, writer, generator, stream, modules.iterator()));
  53         stack.add(new SecurityStream(writer, new SecurityEntity(security)));
  54     }
  55
  56     @Override
  57     public int read() throws IOException {
  58         if (eof) {
  59             return -1;
  60         }
  61         if (reader == null) {
  62             generator.writeStartObject();
  63             generator.flush();
  64             reader = new InputStreamReader(new ByteArrayInputStream(stream.toByteArray()), StandardCharsets.UTF_8);
  65             stream.reset();
  66         }
  67
  68         var read = reader.read();
  69         while (read == -1) {
  70             if (stack.isEmpty()) {
  71                 generator.writeEndObject();
  72                 generator.flush();
  73                 reader = new InputStreamReader(new ByteArrayInputStream(stream.toByteArray()), StandardCharsets.UTF_8);
  74                 stream.reset();
  75                 eof = true;
  76                 return reader.read();
  77             }
  78             reader = new InputStreamReader(stack.pop(), StandardCharsets.UTF_8);
  79             read = reader.read();
  80         }
  81
  82         return read;
  83     }
  84
  85     @Override
  86     public int read(final byte[] array, final int off, final int len) throws IOException {
  87         return super.read(array, off, len);
  88     }
  89 }