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.BufferedReader;
  13 import java.io.ByteArrayInputStream;
  14 import java.io.ByteArrayOutputStream;
  15 import java.io.IOException;
  16 import java.io.InputStream;
  17 import java.io.InputStreamReader;
  18 import java.io.Reader;
  19 import java.nio.charset.StandardCharsets;
  20 import java.util.ArrayDeque;
  21 import java.util.Collection;
  22 import java.util.Deque;
  23 import java.util.List;
  24 import java.util.Map;
  25 import org.opendaylight.restconf.openapi.jaxrs.OpenApiBodyWriter;
  26 import org.opendaylight.restconf.openapi.model.InfoEntity;
  27 import org.opendaylight.restconf.openapi.model.OpenApiVersionEntity;
  28 import org.opendaylight.restconf.openapi.model.SecurityEntity;
  29 import org.opendaylight.restconf.openapi.model.ServerEntity;
  30 import org.opendaylight.restconf.openapi.model.ServersEntity;
  31 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
  32 import org.opendaylight.yangtools.yang.model.api.Module;
  33
  34 public final class OpenApiInputStream extends InputStream {
  35     private final ByteArrayOutputStream stream = new ByteArrayOutputStream();
  36     private final JsonGenerator generator = new JsonFactoryBuilder().build().createGenerator(stream);
  37     private final Deque<InputStream> stack = new ArrayDeque<>();
  38
  39     private Reader reader;
  40
  41     private boolean eof;
  42
  43     public OpenApiInputStream(final EffectiveModelContext context, final String title, final String url,
  44             final List<Map<String, List<String>>> security, final String deviceName, final String urlPrefix,
  45             final boolean isForSingleModule, final boolean includeDataStore, final Collection<? extends Module> modules,
  46             final String basePath) throws IOException {
  47         final OpenApiBodyWriter writer = new OpenApiBodyWriter(generator, stream);
  48         stack.add(new OpenApiVersionStream(new OpenApiVersionEntity(), writer));
  49         stack.add(new InfoStream(new InfoEntity(title), writer));
  50         stack.add(new ServersStream(new ServersEntity(List.of(new ServerEntity(url))), writer));
  51         stack.add(new PathsStream(context, writer, deviceName, urlPrefix, isForSingleModule, includeDataStore, modules,
  52             basePath));
  53         stack.add(new ComponentsStream(context, writer, generator, stream, modules.iterator(), isForSingleModule));
  54         stack.add(new SecurityStream(writer, new SecurityEntity(security)));
  55     }
  56
  57     @Override
  58     public int read() throws IOException {
  59         if (eof) {
  60             return -1;
  61         }
  62         if (reader == null) {
  63             generator.writeStartObject();
  64             generator.flush();
  65             reader = new BufferedReader(
  66                 new InputStreamReader(new ByteArrayInputStream(stream.toByteArray()), StandardCharsets.UTF_8));
  67             stream.reset();
  68         }
  69
  70         var read = reader.read();
  71         while (read == -1) {
  72             if (stack.isEmpty()) {
  73                 generator.writeEndObject();
  74                 generator.flush();
  75                 reader = new BufferedReader(
  76                     new InputStreamReader(new ByteArrayInputStream(stream.toByteArray()), StandardCharsets.UTF_8));
  77                 stream.reset();
  78                 eof = true;
  79                 return reader.read();
  80             }
  81             reader = new BufferedReader(new InputStreamReader(stack.pop(), StandardCharsets.UTF_8));
  82             read = reader.read();
  83         }
  84
  85         return read;
  86     }
  87
  88     @Override
  89     public int read(final byte[] array, final int off, final int len) throws IOException {
  90         return super.read(array, off, len);
  91     }
  92 }