001/*
002 * SPDX-FileCopyrightText: none
003 * SPDX-License-Identifier: CC0-1.0
004 */
005
006package gov.nist.secauto.metaschema.databind.io;
007
008import gov.nist.secauto.metaschema.core.configuration.DefaultConfiguration;
009import gov.nist.secauto.metaschema.core.configuration.IConfiguration;
010import gov.nist.secauto.metaschema.core.configuration.IMutableConfiguration;
011import gov.nist.secauto.metaschema.core.metapath.item.node.IDocumentNodeItem;
012import gov.nist.secauto.metaschema.core.metapath.item.node.INodeItem;
013import gov.nist.secauto.metaschema.core.model.IBoundObject;
014import gov.nist.secauto.metaschema.core.resource.AbstractResourceResolver;
015import gov.nist.secauto.metaschema.core.util.ObjectUtils;
016import gov.nist.secauto.metaschema.databind.IBindingContext;
017import gov.nist.secauto.metaschema.databind.io.ModelDetector.Result;
018
019import org.eclipse.jdt.annotation.NotOwning;
020import org.eclipse.jdt.annotation.Owning;
021
022import java.io.IOException;
023import java.io.InputStream;
024import java.net.URI;
025import java.net.URL;
026import java.util.Map;
027
028import edu.umd.cs.findbugs.annotations.NonNull;
029
030/**
031 * A default implementation of an {@link IBoundLoader}.
032 */
033public class DefaultBoundLoader
034    extends AbstractResourceResolver
035    implements IBoundLoader {
036  public static final int LOOK_AHEAD_BYTES = 32_768;
037  // @NonNull
038  // private static final JsonFactory JSON_FACTORY = new JsonFactory();
039  // @NonNull
040  // private static final XmlFactory XML_FACTORY = new XmlFactory();
041  // @NonNull
042  // private static final YAMLFactory YAML_FACTORY = new YAMLFactory();
043
044  private FormatDetector formatDetector;
045
046  private ModelDetector modelDetector;
047
048  @NonNull
049  private final IBindingContext bindingContext;
050  @NonNull
051  private final IMutableConfiguration<DeserializationFeature<?>> configuration;
052
053  /**
054   * Construct a new OSCAL loader instance, using the provided
055   * {@link IBindingContext}.
056   *
057   * @param bindingContext
058   *          the Module binding context to use to load Java types
059   */
060  public DefaultBoundLoader(@NonNull IBindingContext bindingContext) {
061    this.bindingContext = bindingContext;
062    this.configuration = new DefaultConfiguration<>();
063  }
064
065  @NonNull
066  private IMutableConfiguration<DeserializationFeature<?>> getConfiguration() {
067    return configuration;
068  }
069
070  @Override
071  public boolean isFeatureEnabled(DeserializationFeature<?> feature) {
072    return getConfiguration().isFeatureEnabled(feature);
073  }
074
075  @Override
076  public Map<DeserializationFeature<?>, Object> getFeatureValues() {
077    return getConfiguration().getFeatureValues();
078  }
079
080  @Override
081  public IBoundLoader applyConfiguration(@NonNull IConfiguration<DeserializationFeature<?>> other) {
082    getConfiguration().applyConfiguration(other);
083    resetDetector();
084    return this;
085  }
086
087  @SuppressWarnings("PMD.NullAssignment")
088  private void resetDetector() {
089    // reset the detector
090    formatDetector = null;
091  }
092
093  @Override
094  public IBoundLoader set(DeserializationFeature<?> feature, Object value) {
095    getConfiguration().set(feature, value);
096    resetDetector();
097    return this;
098  }
099
100  @Override
101  public IBindingContext getBindingContext() {
102    return bindingContext;
103  }
104
105  @Override
106  public Format detectFormat(@NonNull URI uri) throws IOException {
107    URI resourceUri = resolve(uri);
108    URL resource = resourceUri.toURL();
109
110    try (InputStream is = ObjectUtils.notNull(resource.openStream())) {
111      return detectFormat(is).getFormat();
112    }
113  }
114
115  @Override
116  public FormatDetector.Result detectFormat(@NonNull InputStream is) throws IOException {
117    return getFormatDetector().detect(is);
118  }
119
120  @NonNull
121  private FormatDetector getFormatDetector() {
122    if (formatDetector == null) {
123      formatDetector = new FormatDetector(getConfiguration());
124    }
125    assert formatDetector != null;
126    return formatDetector;
127  }
128
129  @NonNull
130  private ModelDetector getModelDetector() {
131    if (modelDetector == null) {
132      modelDetector = new ModelDetector(
133          getBindingContext(),
134          getConfiguration());
135    }
136    assert modelDetector != null;
137    return modelDetector;
138  }
139
140  @Override
141  @Owning
142  public Result detectModel(@NotOwning InputStream is, Format format) throws IOException {
143    return getModelDetector().detect(is, format);
144  }
145
146  @Override
147  public <CLASS extends IBoundObject> CLASS load(@NonNull URI uri) throws IOException {
148    URI resourceUri = resolve(uri);
149    URL resource = resourceUri.toURL();
150
151    try (InputStream is = ObjectUtils.notNull(resource.openStream())) {
152      return load(is, uri);
153    }
154  }
155
156  @Override
157  @NonNull
158  public <CLASS extends IBoundObject> CLASS load(@NonNull InputStream is, @NonNull URI documentUri) throws IOException {
159    // TODO: avoid node item
160    return INodeItem.toValue(loadAsNodeItem(is, documentUri));
161  }
162
163  @Override
164  public <CLASS extends IBoundObject> CLASS load(Class<CLASS> clazz, URI uri) throws IOException {
165    URI resourceUri = resolve(uri);
166    URL resource = resourceUri.toURL();
167
168    try (InputStream is = ObjectUtils.notNull(resource.openStream())) {
169      return load(clazz, is, resourceUri);
170    }
171  }
172
173  @Override
174  public <CLASS extends IBoundObject> CLASS load(Class<CLASS> clazz, InputStream is, URI documentUri)
175      throws IOException {
176    // we cannot close this stream, since it will cause the underlying stream to be
177    // closed
178    FormatDetector.Result match = getFormatDetector().detect(is);
179    Format format = match.getFormat();
180
181    try (InputStream remainingStream = match.getDataStream()) {
182      // is autoclosing ok?
183      return load(clazz, format, remainingStream, documentUri);
184    }
185  }
186
187  @Override
188  @NonNull
189  public <CLASS extends IBoundObject> CLASS load(
190      @NonNull Class<CLASS> clazz,
191      @NonNull Format format,
192      @NonNull InputStream is,
193      @NonNull URI documentUri) throws IOException {
194
195    IDeserializer<CLASS> deserializer = getDeserializer(clazz, format, getConfiguration());
196    return deserializer.deserialize(is, documentUri);
197  }
198
199  @Override
200  public IDocumentNodeItem loadAsNodeItem(URI uri) throws IOException {
201    URI resourceUri = resolve(uri);
202    URL resource = resourceUri.toURL();
203
204    try (InputStream is = ObjectUtils.notNull(resource.openStream())) {
205      return loadAsNodeItem(is, resourceUri);
206    }
207  }
208
209  @NonNull
210  private IDocumentNodeItem loadAsNodeItem(@NonNull InputStream is, @NonNull URI documentUri) throws IOException {
211    FormatDetector.Result formatMatch = getFormatDetector().detect(is);
212    Format format = formatMatch.getFormat();
213
214    try (InputStream formatStream = formatMatch.getDataStream()) {
215      return loadAsNodeItem(format, formatStream, documentUri);
216    }
217  }
218
219  @Override
220  public IDocumentNodeItem loadAsNodeItem(Format format, URI uri) throws IOException {
221    URI resourceUri = resolve(uri);
222    URL resource = resourceUri.toURL();
223
224    try (InputStream is = ObjectUtils.notNull(resource.openStream())) {
225      return loadAsNodeItem(format, is, resourceUri);
226    }
227  }
228
229  @Override
230  public IDocumentNodeItem loadAsNodeItem(Format format, InputStream is, URI documentUri)
231      throws IOException {
232    try (ModelDetector.Result modelMatch = detectModel(is, format)) {
233
234      IDeserializer<?> deserializer = getDeserializer(
235          modelMatch.getBoundClass(),
236          format,
237          getConfiguration());
238      try (InputStream modelStream = modelMatch.getDataStream()) {
239        return (IDocumentNodeItem) deserializer.deserializeToNodeItem(modelStream, documentUri);
240      }
241    }
242  }
243
244  @NonNull
245  private <CLASS extends IBoundObject> IDeserializer<CLASS> getDeserializer(
246      @NonNull Class<CLASS> clazz,
247      @NonNull Format format,
248      @NonNull IConfiguration<DeserializationFeature<?>> config) {
249    IDeserializer<CLASS> retval = getBindingContext().newDeserializer(format, clazz);
250    retval.applyConfiguration(config);
251    return retval;
252  }
253}